Micro Motion Signal Converter with Liquid Software - Model 7950 Manuals & Guides

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Operating Manual

MMI-20019471, Rev. AA April 2011

7950 Signal Converter

(With Liquid Software 2010)

Introduction

The Micro Motion for single-stream density and viscosity applications.

Software Version: 2010 – Liquid Density and Viscosity Applications.

Models Covered 7950MAA5*****

7950 liquid signal converter can be used

Micro Motion

7950 Signal Converte

IMPORTANT NOTICE

Because we are continuously improving our products, some of the menus which appear on your instrument’s display may not be exactly as illustrated and described in this manual. However, because the menus are simple and intuitive, this should not cause any major problems.

This manual is concurrent with embedded software version 502010, issue 2.81.

Static precautions

Some parts of the instrument (such as circuit boards) may be damaged by static electricity. Therefore, when carrying out any work which involves the risk of static damage to the instrument, the instructions show the following notice:

CAUTION

At such times you must wear an earthed wrist-strap to protect the instrument.

While carrying out this procedure, you must wear an earthed wrist strap at all times to protect the instrument against static shock.

Safety information

NOTE: This information applies only to those instruments which are mains-powered.

Electricity is dangerous and you risk injury or death if you do not disconnect the power supplies before carrying out some of the procedures given in this manual. Whenever there is such a hazard, the instructions show a notice similar to the following:

WARNING

You must heed any such warnings and make sure that, before you go any further:

Electricity is dangerous and can kill. Disconnect all power supplies before proceeding.

• All power leads are un-powered.

• All power leads are disconnected from the equipment which you are working on unless the

instructions tell you otherwise.

• You obey any other common-sense precautions which may apply to your situation. If you obey these sensible precautions, you can work on the equipment in complete safety.

Battery-backed Memory notice

• It is essential that the Lithium Cell used for the battery backup is installed at all times (other than during replacement). The 7950 Micro Motion

If it is necessary to run the units without batteries for Intrinsic Safety reasons, then the battery should be replaced with a shorting disk inserted in the battery holder. Please consult the factory for further advice.

• Replace the battery when the "Low Battery" system alarm is indicated. The procedure is in Chapter 14.

Signal Converter will not power-up correctly if this battery is missing.

1. About this manual 1.1

1.1 What this manual tells you 1.1

1.2 Who should use this manual 1.1

1.3 Software version covered by this manual 1.1

2. Getting started 2.1

2.1 What this chapter tells you 2.1

2.2 What the examples show you 2.1

2.3 If you need help… 2.1

2.4 Example 1: 7950 with a 7826/35/45/46/47 densitometer 2.2

2.5 Example 2: 7950 with a 7827 viscometer 2.5

2.6 Output Connections 2.8

2.6.1 Relay Ouput 2.8

2.6.2 Digital (Status) Outputs 2.8

3. About the Micro Motion® 7950 3.1

3.1 Background 3.1

3.2 What the 7950 Liquid Signal Converter does 3.1

3.3 Physical description of the 7950 3.2

3.4 Communications 3.3

3.5 Typical installations 3.4

3.6 Checking your software version 3.5

4. Installing the system 4.1

4.1 What this chapter tells you 4.1

4.2 Hazardous and non-hazardous environments 4.1

4.3 Installation procedure 4.1

4.4 Step 1: Drawing up a wiring schedule 4.1

4.5 Step 2: Unpacking the instrument 4.1

4.6 Step 3: Setting DIP switches 4.2

4.7 Step 4: Fitting the 7950 4.3

4.8 Step 5: Making the connections 4.3

4.9 Step 6: Earthing the instrument 4.4

4.10 Step 7: Connecting the power supply 4.5

5. The keyboard, display and indicators 5.1

5.1 What this chapter tells you 5.1

5.2 The layout of the front panel 5.1

5.3 What the display shows 5.2

5.4 How the buttons work 5.2

5.5 Using the buttons to move around the menus 5.2

5.6 Using the buttons to view stored data 5.3

5.7 Using the buttons to edit information 5.4

5.7.1 Text editing 5.4

5.7.2 Multiple-choice option selection 5.5

5.7.3 Numerical editing 5.5

5.7.4 Date and time editing 5.6

5.8 The 795x character set 5.7

5.9 LED indicators 5.7

5.10 Summary of key functions 5.8

6. The menu system 6.1

6.1 What this chapter tells you 6.1

6.2 What the menu system does 6.1

6.3 How the menu system works 6.1

7. Serial Communications and Networking 7.1

7.1 What this chapter tells you 7.1

7.2 7950 Communication capabilities 7.1

7.3 MODBUS from the 7950 point of view 7.1

7.4 Connecting the 7950 to A MODBUS network 7.3

7.4.1 RS-232 connections 7.3

7.4.2 RS-485 (half duplex) connections 7.4

7.5 Configuring the 7950 to be a MODBUS slave 7.6

7.5.1 Port configuration 7.6

7.5.2 High speed list configuration 7.7

7.6 Database access over a MODBUS network 7.8

7.6.1 Introduction 7.8

7.6.2 Database information type 1 : Data values 7.9

7.6.3 Database information type 2 : Data states 7.10

7.6.4 Database information type 3 : Reply size and type 7.11

7.7 Alarm logger access over a MODBUS network 7.12

7.8 High speed list access over a MODBUS network 7.15

8. Alarms and Events 8.1

8.1 Alarms

8.1.1 Alarm types

8.1.2 Alarm indicators 8.1

8.1.3 How alarms are received and stored 8.2

8.1.4 Examining the Status Display and Historical Log 8.2

8.1.5 What the Status Display tells you 8.3

8.1.6 What the entries in the Historical Log tell you 8.3

8.1.7 Clearing all entries in the Historical Alarm Log 8.4

8.1.8 User-defined alarms X and Y 8.5

8.1

8.1.9 User-defined ‘comparison’ limit alarm 8.6

8.1.10 Alarm Logger Output (ALO) 8.7

8.1.11 Alarm Message List 8.8

8.2 Events 8.9

8.2.1 Introduction to 795x events 8.9

8.2.2 Event indicators 8.9

8.2.3 How events are received and stored 8.9

8.2.4 Examining the Event Summary and the Event Log 8.10

8.2.5 What the Event Status Display tells you 8.10

8.2.6 What the entries in the Historical Event Log will tell you 8.11

8.2.7 Clearing all entries in the Historical Event Log 8.12

9. Additional facilities 9.1

9.1 What this chapter tells you 9.1

9.2 Averaging data 9.1

9.3 Selecting units and data formats 9.1

9.4 Limits 9.2

9.5 Fallback values and modes 9.2

9.6 Units which the 795x can display 9.3

9.7 Automated calibration procedures 9.4

9.7.1 Covimat - Static Zero Calibration (in air) 9.4

9.7.2 7827 Liquid Density Transducer 9.6

9.8 Feature: PID Control 9.8

9.8.1 Overview 9.8

9.8.2 Configuration details 9.9

9.8.3 Ramp-limit safeguard 9.11

9.8.4 Anti-Reset-Windup safeguard 9.12

10. Configuring with Wizards 10.1

10.1 Introduction to Wizards 10.1

10.2 Using Wizards 10.1

10.3 Quick-view Guide (Set-up Wizards) 10.3

10.4 Units Wizard Selection 10.4

11. Configuring without the Wizards 11.1

11.1 What does configuration involve? 11.1

11.2 Before you start 11.1

11.3 What will the sections tell you 11.1

11.4 Configuration Guide 11.2

11.5 Live Inputs

11.5.1 Analog Inputs 11.5

11.5.2 Time Period Inputs 11.6

11.6 Temperature Channels (A to K) 11.7

11.7 Pressure 11.8

11.8 Density 11.9

11.8.1 Transducer measured density 11.9

11.5

11.8.2 4x5 Matrix referred density 11.11

11.8.3 API referred density 11.13

11.8.4 Specific gravity 11.15

11.8.5 Degrees Brix 11.15

11.8.6 Degrees Baumé 11.16

11.8.7 Percent Mass 11.16

11.8.8 Percent Volume 11.17

11.8.9 Degrees Twaddell 11.17

11.8.10 Degrees API 11.18

11.8.11 Special Equation Type 1 11.19

11.9 Viscosity 11.21

11.9.1 7827 measured viscosity 11.21

11.9.2 Kinematic viscosity measurement 11.23

11.9.3 4x5 Matrix reference viscosity 11.24

11.9.4 ASTM D341 reference viscosity 11.26

11.9.5 Multi-curve ASTM reference viscosity 11.28

11.9.6 Ignition indexes 11.30

11.9.7 Saybolt Universal Viscosity 11.31

11.9.8 Saybolt Furol Viscosity 11.32

11.9.9 Special Equation Type 4 11.33

11.10 Interface Detection (Density/Viscosity zoning) 11.34

11.11 Custom Applications 11.35

11.11.1 Special Equation Type 2 11.35

11.11.2 General Constants 11.35

11.12 Live outputs 11.36

11.12.1 Analog Outputs 11.36

11.12.2 Information on Averaging and Filtering 11.37

11.13 Other Parameters 11.38

11.13.1 What the “Other parameters” option does 11.38

11.13.2 Passwords and security 11.39

11.13 Multiview 11.41

12. Routine operation (Data maps) 12.1

12.1 Viewing the data 12.1

12.2 Checking the performance of the 795x 12.3

12.3 Printed reports 12.5

12.4 Giving your 795x a tag number 12.6

13. Routine maintenance and fault-finding 13.1

13.1 Cleaning the instrument 13.1

13.2 Fault-finding 13.1

14. Removal and replacement of parts 14.1

14.1 Front panel assembly 14.1

14.2 Display 14.3

14.3 Connector board 14.4

14.4 Microprocessor board 14.5

14.5 Screen and RFI conductive strips 14.5

14.6 Terminal cover seal 14.7

14.7 Gland plate seal 14.8

14.8 Fuses 14.9

14.9 Back-up battery 14.10

15. Assembly drawing and parts list 15.1

15.1 What the drawing and parts list tells you 15.1

15.2 How to obtain spare parts 15.1

Appendices A.1

Appendix A Glossary A.1

Appendix B Blank wiring schedule B.1

Appendix C Technical data for the 7950 C.1

Appendix D Calculations and theory D.1

1. About this manual

1.1 What this manual tells you

This manual tells you how to install, configure, operate, and service the instrument. In addition, some information is given to help you identify and correct some of the more common faults which may occur. However, since repairs are done by changing suspected faulty assemblies, fault-finding to board component level is not covered.

This manual assumes that all devices or peripherals to be connected to the 795x have their own documentatio n which tells you how to install and configure them. For this reason it is assumed that anything which you want to link to the 795x is already installed and working correctly in accordance with the manufacturer’s instructions.

Since the instrument can be used for a wide variety of purposes, it is driven by software specially for your application. This manual gives information about the so ftw are which applie s to y our machine only .

Throughout this manual the term '795x' is used to refer to all members of the 795x family (7950, 795 1, and 7955).

Chapter 1 About this manual

1.2 Who should use this manual

This manual is for anyone who installs, uses, services or repairs the 795x.

1.3 Software version covered by this manual

The software version dealt with in this manual is given on the title page. Chapter 3 tells you about the software is installed in your instrument.

Page 1.1

Chapter 1 About this manual

Page 1.2

2. Getting started

2.1 What this chapter tells you

If you are new to the 7950, the worked examples in this chapter can help you to become familiar with the installation and configuration procedures. The examples are:

• 7950 with a 7826, 7835, 7845, 7846 or 7847 liquid densit y transducer (see page 2.2).

• 7950 with a 7827 viscometer (see page 2.5).

Work through whichever one is most like your installation. Section 2.6 provides details of connections required for the relay output and the digital (status) outputs.

2.2 What the examples show you

Each example shows you how to:

• Wire up a simple system in a non-hazardous area.

• Set the DIP-switches inside the 7950.

• Find the menu from which you start configuration.

• Clear the memory of details of any existing configuration (OPTIONAL).

• Select the appropriate wizard to configure the simple system.

• Work through the wizard and input information.

• View the results of your configuration.

The examples do not give full instructions on how to fit and configure installations. They are intended purely to give you confidence to install and configure your own equipment. Chapter 4 tells you how to make permanent installations.

Chapter 2 Getting started

2.3 If you need help...

If you get into difficulties...

If you get into difficulties when using the wizards, you can abandon the configuration and start again as follows:

1. From the menu, keep selecting NO (usually by pressing the c-button) or, if that option is not available:

2. Press the ENTER button until you can start selecting NO.

3. Carry on with (1) and (2) until you return to the wizard selection menu where you started.

4. Start the worked example again. The configuration you abandoned is cleared from the instrument’s

memory when you begin again.

If you don’t know where the buttons are...

Chapter 5 gives a full explanation of what all the buttons do.

Page 2.1

Chapter 2 Getting started

2.4 Example 1: 7950 with a 7826/35/45/47 densitometer

About this example

This example shows you how to connect a 7826, 7835, 7845, or 7847 densitometer to the 7950, and then uses the Liquid Density 1 wizard to configure the system. The Multi-view button can then be used to instantly display the latest density and temperature readings.

In this example, the Liquid Density 1 wizard configures the connections as follows:

• The densitometer is connected to the Time Period Input 1 terminals.

• The PRT is connected to Analogue Input 1 terminals.

Work through the example by following the instructions below. Refer to Chapter 5 if you are not sure where the buttons are.

Connect the transducer

1. Wire the densitometer to the 7950 terminals, as in Figure 2.1 or Figure 2.2

2. To comply with EMC regulations, you must earth the 7950 to a suitable earth point.

Figure 2.1: Wired connections (7835, 7845, or 7847 with Standard Electronics)

Figure 2.2: Wired connections (7826 Frequency Output densitometer)

Page 2.2

Chapter 2 Getting started

Set DIP switches 3. Make sure that the DIP-switches are set as shown in Figure 2.3.

4-20mA

PRT

Figure 2.3: DIP-switch settings for Example 1

Turn on the power 4. Turn on the power to the system. The system goes through a Power-On-Self-Test (POST)

routine, which takes less than 30 seconds. When it is finished, ignore any flashing alarm lights that may appear.

Go to the wizards menu

5. Press the MENU button to go to Page 1 of the Main Menu (if you aren’t there already).

6. Press the DOWN-ARROW button to go to Page 2 of the menu.

7. Press the c-button to select “Configure”.

8. Press the a-button twice to go to the wizard selection menu.

Clear existing configuration

(This is optional)

9. Press the b-button and then use the UP-ARROW or DOWN-ARROW button to scroll through

the option list until “Initialise” is shown.

10. Press the b-button to select “Initialise”.

11. Press the d-button to confirm that you want to lose the current configuration.

12. Wait a few seconds until “initialise” on display line 2 changes to “Select option”.

Select the wizard 13. Press the b-button then the UP-ARROW or DOWN-ARROW button to scroll through the

option list until “Liquid density 1” is shown.

14. Press the b-button to select “Liquid density 1”.

Start of wizard 15. Press the d-button to answer YES to the ‘Load Liquid density defaults?’ prompt. Enter

densitometer calibration factors

16. Press the d-button to answer YES to the ‘Edit density coefficients?’ prompt.

17. Press the b-button, then input the factor K0 from the Calibration Certificate for the

transducer. (See Figure 2.4 on page 2.4 for an illustration of the certificate).

18. Press the b-button followed by the ENTER button to confirm the K0 value.

19. Enter values for factors K1 and K2 in the same manner as factor K0.

Enter temperature correction factors

20. Press the d-button to answer YES to the ‘Edit Liquid density correction?’ prompt.

21. Press ENTER button to keep the “Temperature” correction selected.

23. Enter values for factors K18 and K19 in the same manner as factor K0.

Skip questions 24. Use the c-button to answer NO to all further prompts until the Wizard is exited. View how you

have configured Line density

View the Multiview display

25. Press the MENU button.

26. Press the a-button twice. The display should now look similar to Figure 2.5, although the

values and text shown may vary.

27. Press the MULTI-VIEW DISPLAY button. The display looks similar to that in Figure 2.6, although the text and values shown may vary.

End of Worked Example 1

Page 2.3

Chapter 2 Getting started

Figure 2.4: Where to obtain values for K0, K1, K18 and K19 from the Calibration Certificate

Line density

265.54 Kg/m3

Live

Figure 2.5: Line density display

Text width setting – a movable boundary between text and value

Page 2.4

Line dens 685.05

Ref Den s 0.000

Temp 29.5 Press 0.00

Text (e.g. parameter names)

Figure 2.6: Multi-view display (after Liquid Density 1 wizard)

Value of paramete

2.5 Example 2: 7950 with a 7827 viscometer

About this example

This example shows you how to connect a 7827 viscometer to the 7950 and then us es the 7827 Density/Viscosity wizard to configure the system. The Multi-view button can then be used to instantly display the latest viscosity, density and temperature readings.

In this example, the 7827 Density/Viscosity wizard configures the connections as follows:

• The viscometer is connected to Time Period Input 3 terminals.

• The PRT is connected to Analogue Input 1 terminals.

Now work through the example by following the instructions below. If you are not sure where the buttons are, refer to Chapter 5.

Connect the transducer

1. Wire the 7827 viscometer to the 7950 terminals, as in Figure 2.7.

2. To comply with EMC regulations, you must earth the 7950 to a suitable earth point.

Chapter 2 Getting started

Set DIP

3. Make sure that the DIP switches are set as shown in Figure 2.8.

switches

Figure 2.7: Wired connections for 7827

4-20mA

PRT

Figure 2.8: Dip-switch settings for Example 2

Page 2.5

Chapter 2 Getting started

Turn on the power 4. Turn on the power to the system. The system goes through a Power-On-Self-Test (POST)

routine, which takes less than 30 seconds. When it is finished, ignore any flashing alarm lights that may appear.

Go to the wizards menu

5. Press the MAIN MENU button to go to Page 1 of the Main Menu (if you aren’t there already).

6. Press the DOWN-ARROW button to go to Page 2 of the menu.

7. Press the c-button to select “Configure”.

8. Press the a-button twice to go to the wizard selection menu.

Clear existing configuration

(This is optional)

9. Press the b-button and then use the UP-ARROW or DOWN-ARROW button to scroll

through the option list until “Initialise” is shown.

10. Press the b-button to select “Initialise”.

11. Press the d-button to confirm that you want to lose the current configuration.

12. Wait a few seconds until “initialise” on display line 2 changes to “Select option”.

Select the wizard 13. Press the b-button then the UP-ARROW or DOWN-ARROW button to scroll through the

option list until “7827 dens/visc” is shown.

14. Press the b-button to select “7827 dens/visc”.

Start of wizard 15. Press the d-button to answer YES to the ‘Load 7827 visco sity defaults?’ prompt. Find out the

viscosity ranges for which the 7827

16. The 7827 is calibrated for one or more of the viscosity ranges: High, Medium, Low or Ultra-

low. Check with the Calibration Certificate to see which ranges your instrument is calibrated for. (See

Figure 2.9.)

is calibrated. Select the ranges

for which your transducer is calibrated

solartron

7827ACALMT VISCOMETER SERIAL NO

VISCOSITY CALIBRATION @ nn C (T-piece)

DENSITY CALIBRATION @ nn C (T-piece)

VISCOSITY CORRECTION DATA Dv = D t + (K20 + K21.1/Q**2 + K22.1/Q**4)

where

Ref No:- xxnnnn/Vn.n

VISCOSITY = V0 + V1.1/Q**2 + V2.1/Q**4

QUALITY

VISCOSITY

(cP)

FACTOR

INSTRUMENT CHECK DATA

nnn.nn

AIR POINT (nn C) QUALITY FACTOR

nn.nn

nnn

nn.nn

nnn

nn.nn

VISCOSITY CODE (for 7945V/6V) = nnnn

nnnn

nn.nn

nnnn

nn.nn

nnnnn

LOW RANGE

ULTRA-LOW RANGE

(n-nnn)

-n.nnnnnE+nn

V0 =

n.nnnnnE+nn

V1 =

n.nnnnnE+nn

V2 =

TIME PERIOD B

DENSITY

(usec)

(Kg/m)

nnn.nnn

n n.n

nnn.nnn air check nnn.nnn

nnn

nnn.nnn

nnn

nnn.nnn

nnn

nnnn

nnn.nnn nnn.nnn

nnnn

MEDIUM RANGE

K20 =

-n.nnnnnE+nn n.nnnnnE+nn

K21 =

n.nnnnnE+nn

K22 =

D = Density (uncorrected) Dt = Density (temperature corrected) Dv = Density (temp and viscosity corrected) TB = Time period B (uS)

Q = Quality Factor

t = Temperature ( C)

DENSITY = K0 + K1.TB + K2.TB**2

Dt = D( 1 + K18(t-20) ) + K19(t-20)

17. Press the d-button to answer YES to the question ‘Edit viscosity coefficient?’

18. Press the b-button, and then use the UP-ARROW button repeatedly until the display

shows the combination of viscosity ranges which applies to your 7827.

19. Press the b-button to select the option and then press the ENTER button to confirm that you want to edit those viscosity ranges.

LOW RANGE

(n-nnn)

-n.nnnnnE+nn n.nnnnnE+nn n.nnnnnE+nn

-n.nnnnnE+nn

K0 = K1 = K2 =

K18 = K19 =

n.nnnnnE-nn n.nnnnnE-nn

-n.nnnE-nn

-n.nnnE+nn

MEDIUM RANGE

(nnn-nnnn)

-n.nnnnnE+nn n.nnnnnE+nn n.nnnnnE+nn

MEDIUM RANGE

(nnn-nnnn)

-n.nnnnnE+nn n.nnnnnE+nn n.nnnnnE+nn

K0 = K1 = K2 =

K18 = K19 =

CAL DATE PRESSURE TEST

-n.nnnnnE+nn

-n.nnnE-nn

-n.nnnE+nn

n.nnnnnE-nn n.nnnnnE-nn

FINAL TEST &

INSPECTION

DATE : xxxxxxx

: nnnnnn : xxxxxxx :nnBAR

HIGH RANGE (nnn-nnnnn)

n.nnnnnE+nn n.nnnnnE+nn n.nnnnnE+nn

ULTRA-LOW RANGE

(n-nnn)

-n.nnnnnE+nn

V0 =

n.nnnnnE+nn

V1 =

n.nnnnnE+nn

V2 =

= nnnn

DENSITY = K0 + K1.TB + K2.TB**2

Dt = D( 1 + K18(t-20) ) + K19(t-20)

HIGH RANGE

(nnn-nnnnn)

n.nnnnnE+nn n.nnnnnE+nn n.nnnnnE+nn

Page 2.6

Figure 2.9: Where to find values for V0, V1, V2, K0, K1, K2, K18 and K19 from the calibration certificate

Enter the calibration factors for each viscosity range

Enter density calibration factors

Enter temperature correction factors

Skip over the next few questions

View Line Dynamic viscosity

View Multi-view display

End of Worked Example 2

Chapter 2 Getting started

20. Repeat for each viscosity range (as selected in step 19):

• Press the b-button, and then input the factor V0 for the viscosity range.

• Press the b-button again, and then ENTER to confirm the details.

• Enter values for calibration factors V1 and V2 in the same manner as for V0.

• Press ENTER button to accept the default value (1.0) for the scale factor.

21. Press the d-button to answer YES to the ‘Edit Density coefficient?’ prompt.

22. Press the b-button then enter the value for factor K0 from the Calibration Certificate.

23. Press the b-button and then press the ENTER button to accept the K0 value.

24. Enter values for factors K1 and K2 in the same manner as for factor K0.

25. Press the d-button to answer YES to ‘Edit Liquid density correction?’ prompt.

26. Press ENTER button to keep the “temperature” correction selection.

27. Enter the value for factors K18 and K19 in the manner as for factor K0.

28. Press the c-button several times to answer NO to all questions until the wizard is exited

29. Press the MAIN MENU button.

30. Press the b-button and then the a-button. The display will look similar to that shown in

Figure 2.10, although the text and values shown may vary.

31. Press the MULTI-VIEW DISPLAY button. The display will look similar to that shown in Figure 2.11, although the text and values shown may vary.

Line dyn visc

1000

Live

Figure 2.10: Line Dynamic Viscosity display

Text width setting – a movable boundary between text and value

Dyn.Visc 1000.00

Kin.Visc 0.000

Dens 0.000

Temp 29.5

Text (e.g. parameter names)

Figure 2.11: Multi-view display (after 7827 Density/Viscosity wizard)

Value of paramete

Page 2.7

Chapter 2 Getting started

2.6 Output Connections

2.6.1 Relay Output

There are 2 contacts: 1: “Normally Open” pin (PL5/1) or

2: “Common” pin (PL5/2).

This output functions as a ‘Watchdog’ for indicating the presence of at least one active alarm. For example, the Normally Open (NO) contact is energised only if there is an alarm.

2.6.2 Digital (Status) Outputs

These outputs are of the open-drain type. Work through parts 1, 2 and 3 to understand all the physical connections that need to be made to the 7950:

1. Power usage - external power (recommended)

“Normally Closed” pin (PL5/3)

This diode protects 7950 against reverse voltages

7950

External power supply provides voltage and current suitable for user selected relay.

Status output

0V from external power supply

Status output common

Figure 2.12: Wiring a Status Output

2. Status Output “Common” Pin

7950 Pin Comment

PL7/9 Use this pin for status outputs 2 to 4. PL7/10 Use this pin for status outputs 5 to 8.

Page 2.8

3. Status Output “Signal” Pin

Status O/P Default Function 7950 Pin

2 Limit Alarm Watchdog (ALO) PL7/2 3 Input Alarm Watchdog (ALO) PL7/3

Refer to Chapter 8 for information on alarm watchdog (ALO) function. Status Outputs 4 to 8 are not used.

3. About the Micro Motion® 7950

3.1 Background

The Micro Motion® 7950 was developed to meet the demand for a reliable, versatile, user-friendl y and costeffective instrument for liquid and gas metering. It has a Motorola 68332 32-bit microprocessor and surfacemounted circuit board components so that it is powerful, reliable and compact.

Features of the 7950 include:

• Simple access to information.

• Comprehensive interrogation facilities.

• Alarm and alarm history facilities.

• A menu-driven, user-friendly interface.

• NEMA 4X, IP65 enclosure.

• Dc powered.

• Three serial communication ports (using RS232 or RS485) for MODBUS communications and printing.

These facilities are described in more detail in the rest of this chapter.

Chapter 3 About the Micro Motion® 7950

3.2 What the 7950 liquid signal converter does

Utilising field transmitters and transducers, the 7950 will calculate:

• Line density.

• Line dynamic viscosity.

• Line kinematic viscosity.

• Temperature (A to K).

• Line pressure.

From these values the 7950 can derive:

• Matrix temperature referred density, corrected for pressure.

• API referred density.

• Saybolt universal viscosity (ASTM D2161).

• Saybolt viscosity at 122 deg.F.

• Saybolt viscosity at 210 deg.F.

• Referred viscosity (ASTM D341 equation, multi-curve ASTM or 4x5 Matrix ).

• Ignition indexes CAII and CII.

Additional features:

• Interface detection - den sity or viscosity zoning

• PID Control

• User defined equations (Types 1, 2 and 4)

• Multi-view (display key)

• Analogue Outputs

• Security.

Page 3.1

Chapter 3 About the Micro Motion® 7950

3.3 Physical description of the 7950

The 7950 is a wall-mounted instrument housed in a one-piece case. The upper part of the instrument has a panel on which are mounted the keyboard and display. Below this, and stepped back slightly, is a terminal cover which, when removed allows access to the electrical connectors on the connector board inside the instrument. All wiring enters the case from underneath, through the gland plate which has to be drille d for the purpose.

The connector board is mounted vertically inside the back of the case. The microprocessor board is attached, by six screws and stand-offs, to the back of the keyboard and display.

The upper and lower parts of the instrument are separated by a horizontal metal plate (the screen) which helps to protect the instrument against electro-magnetic interference.

Page 3.2

Figure 3.1: The 7950 and its major assemblies

3.4 Communications

The 7950 can operate as a MODBUS slave. It can:

• Download a configuration from a PC, DCS, etc.

• Upload a configuration.

• Monitor random locations in the 7950.

• Interrogate the alarm and data logger buffers.

• Manipulate the alarm and data logger buffers.

• Set random locations with new data.

• Instigate printed reports.

Chapter 7 in this manual gives full details on communications with the 7950 instrument.

3.5 Typical installations

Figure 3.2 (below) and Figure 3.3 (on page 11.4) illustrate two typical applications that are supported.

Chapter 3 About the Micro Motion® 7950

Part of pipeline

4-wire PRT

Transducers and transmitters

Static pressure transducer

Density transmitter Temperature element (PRT)

7950

solartron

4-20mA

Frequency

instruments

8 9

4 5

1 2

+/-

CLR EXP

1 2

Alarm Analogue outputs

Printer

MODBUS communications to and from host computer

Figure 3.2: Liquid Density Application

Page 3.3

Chapter 3 About the Micro Motion® 7950

Part of pipeline

4-wire PRT

Frequency

4-20mA (from Covimat range) OR Frequency (from a 7827)

MODBUS communications to and from host com

Figure 3.3: A typical oil blending application

3.6 Checking your software version

Transducers and transmitters

Viscometer (Covimat or 7827 transducer)

Density transmitter

Temperature element (PRT)

solartron

instruments

8 9

4 5

1 2

+/-

CLR EXP

1 2

7950

uter

Alarm Analogue outputs

Printer

The 7950 is driven by pre-loaded software which differs according to the application for which the instrument is to be used. To check hardware configuration, see Ordering Information in Appendix C.

PREFIX:

HARDWARE PLATFORM

50 7950 51 7951

DIGIT 1:

METERED PRODUCT

1 GAS 2 LIQU ID 3 BOTH 4 OTHER

PREFIX DIGIT 1 DIGIT 2 DIGIT 3 DIGIT 4

DIGIT 2:

FLOW METER

0 NONE 1 ORIFIC E 2 TURBINE/PD 3 VENTURI 4 MASS 5 MULTI

DIGIT 3:

STREAMS/ CHANNELS

1 SINGLE 2 DUAL 3 TRIPLE 4 QUAD 5 1, 2, 3 or 4

SOFTWARE VERSION NUMBER

DIGIT 4:

SPECIAL

0 – 9

Figure 3.4: Software version number

For example, for a 7950 Liquid Signal Converter, the software version number is 502010. You can find the software version number in two ways:

1. It is printed on a label at the rear panel of the 7950.

2. It is written into the menu structure – see Chapter 12.

Page 3.4

4. Installing the system

4.1 What this chapter tells you

This chapter gives you full instructions for installing the 7950.

It does not go into detail about how to install any peripheral devices (such as transducers, computers or printers) which can be connected to the 7950. For this information you must refer to the documentation supplied with these items.

4.2 Hazardous and non-hazardous environments

If all or part of an installation is in an area where there is the risk of fire or explosion, then barriers usually have to be wired into the circuit. However, some instruments are explosion-proof and barriers are not therefore needed.

You must follow the manufacturers’ instructions and safety recommendations fully.

4.3 Installation procedure

Chapter 4 Installing the system

Briefly, the procedure is:

Step 1: Draw up a wiring schedule. Step 2: Unpack the 7950. Step 3: Set the DIP switches. Step 4: Fit the 7950. Step 5: Make all external connections. Step 6: Earth the installation. Step 7: Connect power supply.

The steps in the procedure are explained in the following sections.

4.4 Step 1: Drawing up a wiring schedule

Before you make any connections, you must draw up a wiring schedule to help you identify wiring colours and make sure that you do not connect more items of any given type than you are allowed to. (If you are in doubt, check the specification in Appendix C.)

A blank copy of a wiring schedule is given in Appendix B.

4.5 Step 2: Unpacking the instrument

Remove the instrument from its packing and examine it to see if any items are loose or if it has been damaged in transit. Check that all items on the shipping list are present. If any items are missing or if the equipment is damaged, contact your supplier immediately for further advice.

What should be supplied with the 7950:

• Labels #1 - #20 for identifying the sockets.

• 4-way free socket for DC input.

• 3-way free socket for AC input.

• 10-way free socket for I/O (13 off).

• 1.6A and 400mA fuses (Note: these are spares).

• An operating manual (this manual).

Page 4.1

Chapter 4 Installing the system

Other items you must supply yourself:

• Cable glands (if you want to use them).

• Fixings (such as screws and plugs) suitable for fixing the 7950 to a wall.

Note: If you have ordered optional, additional facilities (such as extra outputs) these are already installed in

the machine.

4.6 Step 3: Setting DIP switches

The 7950 is supplied with the DIP-switches in these default settings:

• Turbine power: 8 VOLTS

• Security switch: NONSECURE

• Input 1 PRT

• Inputs 2-4: 4-20mA

Figure 4.1: Dip switches on the Connector Board

If you want to change these settings, do this as follows:

• Security The 7950 can work in a non-secure or securable mode. In non- secure mode, anyone can have access to the signal converter. In securable mode, access to many of the signal converter’s functions can be protected by a password. At this stage, setting the DIP switch only determines whether or not the instrument is capable of being protected because the actual setting of the security is carried out later when the instrument is configured.

• PRT or analog (4-20mA)

inputs

When you have set the dip switches, replace the terminal plate. Note: The 7950 is always shipped from the factory with the security DIP-switch set to non-secure.

There are four dip switches (one per channel) which determine whether the input to each channel is from a PRT or analogue (4-20mA) transmitter. Set each DIP switch as you require.

Note: You also have to configure the inputs. This is explained in

Chapter 11.

Page 4.2

4.7 Step 4: Fitting the 7950

Caution:

You must not fit the 7950 where it may be subjected to extreme conditions or be liable to damage. For further information about the environmental conditions within which it can operate, see Appendix C.

Chapter 4 Installing the system

Figure 4.2: Mounting details for the 7950

1. Undo and remove the six screws which secure the gland plate to the underneath of the instrument. Remove the gland plate.

2. Drill whatever holes are required in the plate to allow the cables to enter the instrument. Do not replace the gland plate at this stage.

3. Drill a pilot hole in the wall. Then, using whatever fixings (such as wall plugs) are suitable for the type of wall, turn in a screw so that its head sticks out far enough so that the keyhole-shaped slot at the back of the case can fit over it.

4. Fit the instrument on the wall.

5. Undo the four screws and remove the terminal cover.

6. Mark through the two instrument mounting holes then take the instrument off the wall.

7. Drill holes for screws at the marked positions. The holes should be wide enough to take wall plugs if these are to be used.

8. If wall plugs are to be used, insert them into the holes.

9. Hang the instrument on the wall, insert the screws and tighten them sufficiently to hold the instrument in place.

10. Replace the terminal cover.

4.8 Step 5: Making the connections

1. Refer to the documentation supplied with the external equipment to see if you have to carry out any special procedures when connecting them to the 7950. Take special notice of any information about complying with EMC regulations.

2. Pass the cables through the holes in the gland plate then connect the sockets to the wiring using your schedule and the connection diagram (in Chapter 5) to help you.

3. Check the wiring thoroughly against the schedule and wiring diagram.

4. Connect the sockets to the plugs on the connector board.

5. Replace the gland plate.

Page 4.3

Chapter 4 Installing the system

4.9 Step 6: Earthing the instrument

Caution: Incorrect earthing can cause many problems, so you must earth the chassis and the electronics correctly. The way in which you do this depends almost entirely on the type of installation you have and the conditions under which it operates. Therefore, because these instructions cannot cover every possible situation, the manufacturers recommend that earthing procedures should only be carried out by personnel who are skilled in such work.

The Chassis of the 7950 must be earthed in all cases; both for safety reasons and to ensure that the installation complies with EMC regulations. Do this by connecting an earth lead from the stud on the gland plate to a local safety earth such as pipework or some other suitable metal structure.

Connector board

Earth stud

Chassis earth lead to external earth

Internal earth lead

Gland plate

Figure 4.3: Earthing the chassis of the 7950

In addition to earthing the chassis, you may have to make extra earth connections in some cases, depending on the installation requirements. Details of this are given in Appendix C.

Page 4.4

4.10 Step 7: Connecting the power supply

Warning:

• Electricity is dangerous and can kill.

Caution:

• Power connections should not be made by anyone other than a qualified electrician.

Follow these 5 steps:

1. Switch off and disconnect all power supplies to the instrument (if you haven’t already done so).

2. If you are using cable glands, insert one into the appropriate hole in the gland plate.

3. Pass the power cable through the cable gland.

4. Before going any further, re-check that the wiring is connected correctly.

5. The instrument can work on either 110-230V a.c. or from a d.c. supply. Make the power connection, as follows:

• For a.c. power: Plug the power connector into plug PL1.

• For d.c. power: Plug the power connector into plug PL2.

Note that you can connect the 7950 to both the d.c. and a.c. supplies if you want a d.c. back-up in case the mains supply should fail.

The instrument goes through the following Power-On-Self-Test (POST) routine:

Chapter 4 Installing the system

• The display shows a sequence of characters or patterns to prove that all elements of the display are

working. There is a pause of five seconds between each change of pattern.

• The program ROM is checked against a checksum. The display shows how the test is proceeding.

• Critical data are checked. The display shows the result of this check.

• The coefficients are checked. The display shows the result of this check.

• The battery-backed RAM is checked. The display indicates progress.

• Any saved programs are checked. The display shows the number of programs and their status. Note

that, for a new machine, there are no stored programs.

• If a battery is fitted, its condition is checked and reported.

Note that, when the power is switched on, alarm LEDs may light up. You can ignore these for the moment - alarms are explained in Chapter 8. As long as the POST is completed satisfactorily, the 7950 is ready to be configured (see Chapters 10 and 11).

If the POST fails to complete, switch off the power and check all connections and the DIP switch settings. Then re-connect the power supply. If the POST still fails to complete, switch off again and contact your supplier.

Page 4.5

Chapter 4 Installing the system

Page 4.6

Chapter 5 The keyboard, display and indicators

5. The keyboard, display and indicators

5.1 What this chapter tells you

This chapter tells you:

• How the front panel is laid out.

• What the buttons and indicators do.

• What characters you can display.

5.2 The layout of the front panel

Figure 5.1 shows the layout of the keyboard. The diagrams at the end of this chapter give a visual sum mary of what each of the buttons do.

1. DOWN-ARROW 7. ENTER 13. PRINT MENU

2. UP-ARROW 8. INFORMATION MENU 14. STREAM/RUN SELECT

3. MULTI-VIEW DISPLAY 9. LIMIT ALARM LED 15. F1 (software specific function)

4. LEFT-ARROW 10. INPUT ALARM LED 16. SECURITY LED

5. RIGHT-ARROW 11. SYSTEM ALARM LED

6. BACK 12. MAIN MENU

Figure 5.1: The layout of the front panel

Page 5.1

Chapter 5 The keyboard, display and indicators

5.3 What the display shows

The display can show the following information:

• Numerical data in floating point, exponent or integer formats.

• Text descriptors.

• Units of measurement (if applicable).

• Status of parameters i.e. set, live, failed or fallback (if applicable).

• Alarm and event information.

• Current time and date.

• Identification number (location ID) of parameter.

• Stream (metering-run) identification number (if applicable).

5.4 How the buttons work

The buttons let you:

• Move around the menus.

• View data stored in the 795x – VIEW mode.

• Edit the data – EDIT mode.

Some buttons do different things according to where you are in the menu system. For example:

ENTER button This button does nothing until you get into EDIT mode. After you have

c button When you move through the menu structure this selects any menu

INFORMATION MENU button

PRINT MENU

button

edited the data of a parameter, pressing ENTER accepts the changes and puts the 795x back into VIEW mode.

choice shown against the button. However, when in VIEW mode, pressing

This button does nothing if you are in EDIT mode. At other times, it takes you to a special menu that provides information on alarms, events, flow status and 795x operating mode.

This button does nothing if you are in EDIT mode. At other times, it takes you to a special menu dealing with data archiving and printing of reports.

c lists the display units.

5.5 Using the buttons to move around the menus

A general tour of the menu system is provided in chapter 6. The buttons, which you can use to move around the menu system, are:

UP-ARROW Moves the display up to the previous page of the menu. If there is no

DOWN-ARROW Moves the display down to the next page of the menu. If there is no

previous page, this button does nothing.

next page, this button does nothing.

Page 5.2

a - d buttons Each of these buttons selects the menu choice next to it. If there is no

BACK Returns you to the previ ous step.

menu choice next to a button, that button does nothing.

Chapter 5 The keyboard, display and indicators

MAIN MENU Moves you straight to page 1 of the top-level menu.

INFORMATION MENU

PRINT MENU Takes you to a special menu dealing with data archiving and printing

MULTI-VIEW

F1 The use of this button is dependent on the functionality of the

Note: All other buttons have no effect when moving around the menus.

Takes you to a special menu providing information on alarms, events, flow status and 795x operating mode.

of reports. You can define one or more display pages, each showing up to four

items of data, lines of descriptive text, or both. Pressing MULTI- VIEW shows the first display page you have defined. Use the up/down arrow buttons to page up and page down.

application software. If this button is in use, it will be mentioned in later chapters.

5.6 Using the buttons to view stored data

When a software parameter screen is viewed, after selection from the menu, the display is in VIEW mode. Figure 5.2 shows a typical display when you view a software parameter screen. In VIEW mode, all information is

in a right justified format.

Figure 5.2: A typical software parameter screen (in VIEW mode)

What the display shows

Line 1: Shows the parameter description. (Some words are abbreviated.) Line 2: Shows the present value (or text for indirection type). Line 3: Shows the measurement units (if any). This line is blank if there are n o units. Line 4: The right-hand side shows LIVE, SET, FB (FALLBACK) or FAIL to indicate the state of the

present value shown in Line 2, where appropriate. These indications mean: LIVE – The data shown is live data received from the transducer/transmitter connected to

the 795x or calculated by the 7858 rather than a set value.

SET – There is a fixed value for the data; this value does not change unless you enter a

new fixed value or make it live.

FB – A fallback or default value has been used to obtain the value for the data. FAIL – The live input has failed, most likely due to no transducer/transmitter being

connected or a calculation failed to complete due to incorrect configuration.

An alarm will be raised causing the Input Alarm LED to flash on the front panel. For

troubleshooting this alarm, see chapter 8.

Optionally, Line 4 may also show the parameter’s unique identifica tion number (location ID ), which is required w hen setting up certain features e.g. Multi-view. You can toggle this in formation on/off by the ‘a’ button.

Page 5.3

Chapter 5 The keyboard, display and indicators

In VIEW mode, the buttons that you can use are:

‘

a’ button On/off toggle for displaying the parameter’s uni que identification number

‘

b’ button Puts the 795x into EDIT mode so that you can edit the data on line 2. The

‘

c’ button Puts the 795x into EDIT mode so that you can select from a list of the units

‘

d’ button Puts the 795x into EDIT mode so that you can select a status (Set or Live).

(location ID). This is displayed to the left of the status indication on line 4.

data being edited is left justified whilst in EDIT mode. (See next section)

in which the data can be displayed. The units are left justified whilst in EDIT mode. (See next section)

The status is left justified whilst in EDIT mode. (See next section)

STREAM / RUN SELECT

BACK Returns you to the previous step.

MAIN MENU Takes you straight to page 1 of the top-level menu.

If there is more than one stream (metering-run) and there is a number on the far left of display line 4, this button will select another stream (meteringrun). The screen will be refreshed with attributes (value, units and status) for that stream (metering-run).

5.7 Using the buttons to edit information

You can:

• Edit text.

• Select an option from a multiple-choice list.

• Edit numerical information.

• Edit the date and time.

5.7.1 Text editing

Once in EDIT mode (see earlier), the buttons that you use to edit text are:

LEFT-ARROW Moves the cursor to the left, along the line of text you are editing.

Page 5.4

RIGHT-ARROW Moves the cursor to the right, along the line of text you are editing.

UP-ARROW This button changes the character at the current cursor position. It scrolls

DOWN-ARROW Changes the character at the current cursor position. It scrolls

0 - 9 buttons Each button enters a single digit.

b’ button If you are satisfied with the changes you have made, press b to accept the

‘

forwards through the alphanumeric character set. Stop when the

character you want is displayed.

backwards through the alphanumeric character set. Stop when the character you want is displayed.

changes and go back to VIEW mode. (The ENTER button also does this.)

Chapter 5 The keyboard, display and indicators

ENTER If you are satisfied with the changes you have made, press EN TER to

CLEAR This clears a line of text.

BACK If you do not want to keep the changes you have made, press the BACK

PLUS / MINUS Toggles between lower and upper case letters.

accept the changes and go back to VIEW mode. (The ‘

button to abandon the changes and go back to VIEW mode.

5.7.2 Multiple-choice option selection

Once in EDIT mode (see earlier), the keys that you use to select from a multiple-choice list are:

UP-ARROW Scrolls up through the available options.

DOWN-ARROW Scrolls down through the available options.

‘

b’ button If editing the data (on display line 2) and you are satisfied with the

change you have made, press the ‘ back to VIEW mode. (Note: The ENTER button also does this.)

b’ to accept the change and go

b’ also does this.)

‘

c’ button If editing the measurement unit selection and you are satisfied with the

‘

d’ button If editing the status selection and you are satisfied with the change you

ENTER If you are satisfied with the change you have made, press the ENTER

CLEAR Restore the previous contents.

BACK If you do not want to keep the changes you have made, press the

change you have made, press the ‘ to VIEW mode. (Note: The ENTER button also does this.)

have made, press the ‘ mode. (Note: The ENTER button also does this.)

button to accept the change and go back to VIEW mode.

BACK button to abandon the changes and go back to VIEW mode.

d’ to accept the change and go back to VIEW

5.7.3 Numerical editing

Once in EDIT mode (see earlier), the buttons that you use to edit numerical data are:

LEFT-ARROW Erases the digit to the left of the cursor.

0 - 9 buttons Each butto n enters a single digit.

c’ to accept the change and go back

PLUS / MINUS This changes the sign of the number. Pressing it will toggle between

Page 5.5

PLUS and MINUS signs.

Chapter 5 The keyboard, display and indicators

DOT Inserts a decimal point.

EXPONENT Use this button if you want to show numbers in exponent form.

‘

b’ button If you want to accept the changes you have made, press the ‘b’. The

ENTER If you want to accept the changes you have made, press the ENTER key.

CLEAR Clears the line you are currently editing.

BACK If you do not want to keep the changes you have made, press the BACK

Numerical entry

When you type in a number the first digit appears at the left of the display and each successive digit is then positioned to the right of the one just entered. A number being entered over-types any existing number.

Parameter identification number (Location ID) entry

These appear on the display in the same way as for numerical entry. However, when you accept the nu mber (by pressing ‘ encounter this type of ‘pointer’ (indirection) editing if configuring the Multi-view display (see chapter 11).

b’ or ENTER), the text descriptor of the parameter with that particular number appears on line 2. You will

795x will then revert to VIEW mode. (Note: ENTER also does this.)

The 795x will then revert to VIEW mode. (Note: ‘

button to abandon the changes and go back to VIEW mode.

b’ also does this.)

5.7.4 Date and time editing

The date and time are displayed in the format: dd-mm-yyyy hh:mm:ss. When you edit the date and time, the cursor moves to the right but skips the ‘:’ and ‘-’ characters.

LEFT-ARROW Moves the cursor to the left.

RIGHT-ARROW Moves the cursor to the right.

0 - 9 buttons Each button enters a single digit.

‘b’ button If you want to accept the changes you have made, press ‘b’. The

ENTER If you want to accept the changes you have made, press ENTER.

CLEAR Restore the previous contents.

BACK If you do not want to keep the changes you have made, press the

The new date and time is validated. An invalid date and time is causes the message “Bad date/time” to appear onscreen for a few seconds before the previous content is restored.

795x will then revert to VIEW mode. (Note: ENTER also does this.)

The 795x will then revert to VIEW mode. (Note: ‘

BACK button to abandon the changes and go back to VIEW mode.

b’ also does this.)

Page 5.6

5.8 The 795x character set

You can use any of the 96 characters shown below as part of your display.

Chapter 5 The keyboard, display and indicators

Figure 5.3: The 795x character set

5.9 LED indicators

Security Indicator This LED shows the present security level of the system.

• RED FLASHING – The instrument is at Calibration level.

• RED – Engine er level: the instrument can be configured.

• ORANGE – Operator level: limits can be changed.

• GREEN – World level: no parameters can be changed.

Note: For more information about these, see Chapter 11.

Security Level LED.

Figure 5.4: Alarm Indicators

Alarm Indicators These are the Input, System and Limit alarms. For more information about these,

refer to Chapter 8: “Alarms and Events”.

Figure 5.5: Alarm Indicators

Page 5.7

System alarm LED. Input alarm LED. Limit alarm LED.

Chapter 5 The keyboard, display and indicators

5.10 Summary of button functions

The tables here provide a visual summary of the function for each button when in various modes.

Page 5.8

Table 5.1: Summary of what the buttons do (Part 1 of 2)

Chapter 5 The keyboard, display and indicators

Table 5.2: Summary of what the buttons do (Part 2 of 2)

Page 5.9

Chapter 5 The keyboard, display and indicators

Page 5.10

Chapter 6 The menu system

6. The menu system

6.1 What this chapter tells you

Before you can configure and operate the 795x, you should have some understanding of how the menu system works. The menus are simple and intuitive, so they should present no problems to the average user.

This chapter gives you a general tour, showing how to navigate the menu system to find application parameter screens and other types of screen such as for entering passwords.

Note:

The menus and parameters will differ between software versions, and can differ between releases of a software version. Chapter 12 features tables showing the routinely used (operator) parts of the menu system used in your software.

6.2 What the menu system does

The menu system lets you:

• Configure the 795x.

• Operate it.

• View data and settings stored in the 795x.

• Edit data stored in the 795x.

6.3 How the menu system works

When you power-on the 795x, the menu system appears immediatel y after the routine Power-On-Self-Test (POST) is completed. If it is the first power-on since the software was installed, a screen appears showing the software version number and the issue number e.g. 2550 Iss 1.00.00. if this is not the case, the screen will be the last visited menu location prior to powering off (or a power failure).

Press the MAIN MENU button once and page 1 of the top-level menu will appear (see Figure 6.1).

The menu system is a tree-like structure that repeatedly branches to lower levels until a final screen is reached. Page 1 of a top-level menu shown in Figure 6.1. It comprises four menu choices – Flow rates, Flow totals, D e nsity and Viscosity.

Each menu choice has a description e.g. “Flow rates” and a triangular icon e.g. menu choice. A non-filled, triangular icon ( A filled, triangular icon (

) indicates the menu choice leads to a parameter screen.

) indicates the menu choice leads to a lower-level menu (sub-menu).

alongside to indicate the type of

Note: The menus may be different in your software.

Figure 6.1: page 1 of a top-level menu

Page 6.1

Chapter 6 The menu system

Each menu choice is associated with a lettered button on the front panel on Display Line 1 is associated with the

a button. Similarly, a menu choice on Display Line 2 is associated with the

a, b, c or d. For example, a menu choice

b button, and so on. If there is no menu choice on a display line, the associated letter button will not do anything.

When you do make a menu choice from a menu using the lettered buttons, the display changes to show the selected lower-level menu or a parameter screen.

Figure 6.2 shows an example where pressing the the

b button leads to a lower-level menu for “Flow totals”.

Using the BACK button will return you to the previous menu level.

a button will lead to a lower-level menu for “Flow rates”. Similarly,

Note: The menus may be different in your software.

Figure 6.2: Menu Choice Selection

Where a menu has more choices than can fit on to the 4-line display, the menu comprises of t wo or more pages. Vertical arrow icons appear on the left-hand side of display to indicate there are further pages on the same menu level. Figure 6.3 shows how you can scroll up or down between the pages by using the UP-ARROW and DOWN-

ARROW buttons. These buttons will do nothing unless there is a page to scroll to.

Note: The menus may be different in your software.

Figure 6.3: Pages of a Main Menu

Page 6.2

Chapter 6 The menu system

At the lowest levels in each branch of the menu system, there are parameter screens. Figure 6.4 shows how to navigate to the parameter screen for <MeterRun Temperature>. All parameter screens feature a solid, black, triangular shaped mark in the bottom-left corner of Display Line 4.

Note: Full details about editing parameters can be found in Chapter 5.

Note: The menus may be different in your software.

Figure 6.4: A typical software parameter screen

Page 6.3

Chapter 6 The menu system

Returning to the top-level menu again, there are menu choices that are common to all software versions (Figure 6.5). In addition, you’ll encounter them in subsequent chapters.

All other menu choices on the Main Menu (e.g. “Flow rates”) are for operators to quickly find final measurements and other calculation results. Chapter 12 has tables showing these menus in more detail.

Leads to menus for viewing interim results of measurements and other calculations, Inputs, Outputs, etc. (See Chapter 12 for a full map)

Leads to menus for editing measurement tasks for your installation. (See Chapters 8 - 11).

Leads to a screen for entering a password to change security level. (See Chapter 11).

Leads to a screen detailing the software version number.

Figure 6.5: Menus common to all software versions

Leads to a screen where you can view/edit text to identif

the 795x.

Leads to menus where you can view/edit the time and date, plus machine cycle timing.

Page 6.4

Chapter 7 Serial Communications and Networking

7. Serial Communications and Networking

7.1. What this Chapter tells you

This Chapter is a comprehensive guide to serial communications and networking with the 7950.

Since, this subject area is vast (with countless reference books), the scope is restricted to the 7950 point of view. Therefore, it is assumed that the reader has a reasonable working knowledge of data communications an d networking.

A recommended reference for this Chapter is the 1992 edition of “Modicon Modbus Protocol Reference Guide (PL_MBUS-300 Rev.D)”. This covers the MODBUS protocol in much greater depth.

7.2. 7950 Communication Capabilities

The 7950 has extensive facilities for communicating with devices using the MODBUS protocol.

Two serial interface standards supported - RS-232C and RS-485 (1/2 duplex). They are software selectable if there is a choice for a particular port.

Table 7.1 Serial ports and supported serial interfaces

Hardware and

connection

7950 RS-232C RS-232C RS-232 or 485

Port 1 Port 2 Port 3

7.3. MODBUS from the 7950 point of view

Introduction

The Modicon MODBUS specification is designed to transfer data in 1-bit (coil) or 16-bit (register) blocks. This protocol has not been designed to deal with data, such as floating point numbers, which require a minimum of 32-bit blocks. For this reason, every manufacturer of computer equipment which deals with this type of data must decide in which way the protocol should be extended. As a result, many different implementations exist for the transfer of 32-bit floating point data.

Floating Point numbers

Floating point data within the 7950 are stored as 64-bit IEEE numbers. When requested over a MODBUS link, they are automatically translated into 32-bit IEEE numbers.

A requester must ask for the register required with the quantity of registers. The response will be the 32-bit IEEE number.

Word swap

Since Modicon did not define 32-bit transfers, the order of the words for a 32-bit value is also not defined. The 7950 provides the facility to choose whether the first or second word is the most significant. This feature is individually selectable for each port.

Page 7.1

Chapter 7 Serial communications and Networking

Flow totalisers

Since a totalisers value builds continuously to a maximum and then is re-set to 0, this type of data cannot be transferred in quite the same way as a conventional floating point. The reason is because of the way in which a floating point number is stored.

A 32-bit floating point number can represent only 7 significant digits. Therefore as the value grows, less and less digits are available for the fractional part. In addition, 7 digits are not generally acceptable for a totaliser .

For these reasons, the 7950 returns totalisers as 32-bit integers. The fractional part is also available in a separate register if required.

Supported Commands

The 7950 supports two commands:

1. Command 3 - Read multiple registers

2. Command 16 - Write multiple registers All data stored within the 7950 is represented by one or more 16-bit registers. There may be registers which

contain a collection of bits. In this case, a 16-bit register is still used rather than provide individual bit (coil) access.

The database in the 7950 uses a unique index (i.e. location number) for each parameter. Although a location number is not normally displayed, pressing the ‘a’ button when a database variable is di splayed, will cause the location number to appear on the 4

line.

MODBUS register numbers are always expressed as the database location number minus 1. Therefore, a requesting device will ask for MODBUS register 16 in order to read the data in database locatio n 17.

Virtual slaves

The 7950 can respond to more than one MODBUS address on a single port. The address set for the MODBUS slave function is used for the 7950 database. However, it is possible to configure the 7950 to make available the alarm logger, event logger and 2 high speed list systems on consecutive MODBUS addresses beyond the base

address. e.g. Modbus slave (base) address = 10 (0x0A) Alarm logger address = 11 (0x0B) High speed list1 = 12 (0x0C) High speed list2 = 13 (0x0D)

Page 7.2

Chapter 7 Serial Communications and Networking

7.4. Connecting the 7950 to A MODBUS network

7.4.1. RS-232 connections

RS-232C serial interface (Port 1)

7950 (Klippon) Function

Tx 1 PL3/1 Transmit data Rx 1 PL3/2 Receive data Common PL3/3 0V GND (Signal Ground)

RS-232C serial interface (Port 2)

7950 (Klippon) Function

Tx 2 PL3/5 Transmit data Rx 2 PL3/6 Receive data Common PL3/7 0V GND (Signal Ground) RTS 2 PL3/8 Clear to send CTS 2 PL3/9 Request to send Protect GND PL3/4 Frame (chassis) protection

RS232 Pins (Port 3)

7950 (Klippon) Function

Tx 3 PL4/1 Transmit data Rx 3 PL4/2 Receive data Common PL4/3 0V GND (Signal Ground) RTS 3 PL3/4 Clear to send CTS 3 PL3/5 Request to send Protect GND PL4/8 Frame (chassis) protection

A simple MODBUS network can consist of just two devices. They could be an IBM compatible PC and a 7950 connected by a RS-232C ‘straight through’ cable.

PC D-type

Com port

3 5

Signal Ground

Note: Connect to cable screen at a single point

PC connection to 7950 Port 1

RS-232 wiring with no RTS/CTS handshaking

Figure 7.1

Tx Rx

7950

PL3/1 PL3/2

PL3/3 PL3/4

Page 7.3

Chapter 7 Serial communications and Networking

PC D-type

Com port

7950

7 8

Note: Connect to cable

screen at a single point

PC connection to 7950 Port 2

RS-232 wiring with RTS/CTS handshaking

7.4.2. RS-485 (half duplex) connections

RS-485 serial interface (Port 1)

There is no support for RS-485 on port one.

RS-485 serial interface (Port 2)

Signal Ground

RTS

CTS

Figure 7.2

PL3/5

PL3/6

PL3/3 PL3/8 PL3/9

PL3/10

Page 7.4

7950 (Klippon) Purpose

No support Transmit/receive data + for RS-485 Transmit/receive data -

on port 2 0V GND (Signal Ground)

RS-485 serial interface (Port 3)

7950 (Klippon) Purpose

Rx/Tx 3a PL4/6 Transmit/receive data + Rx/Tx 3b PL4/7 Transmit/receive data Common PL4/3 0V GND (Signal Ground) Protect GND PL4/8 Frame (chassis) protection

You can establish a MODBUS network by connecting a flow-meter prover computer to multiple stream flow

computers with a RS-485 cable.

Chapter 7 Serial Communications and Networking

7950 7950

7950

Stream 2Stream 1Prover

PL4/6

PL4/7 PL4/3

Tx/Rx+

Tx/Rx-

Signal Ground

PL4/6

PL4/7 PL4/3

Tx/Rx+

Tx/Rx-

Signal Ground

PL4/6 PL4/7 PL4/3

PL4/8

Note: 7950 only. Connect to cable screen at a single point

Figure 7.3

Page 7.5

Chapter 7 Serial communications and Networking

7.5. Configuring the 7950 to be a MODBUS slave

7.5.1. Port configuration

Select the menu: <“Configure”>/<“Other parameters”>/<“Communications”> and then proceed through the data

location check-lists that are applicable to the installation:

• Port one is connected to a MODBUS network

Parameters Instructions

Comms port1 owner Select the “Modbus slave” option. Default selection is “None” Port1 Baud rates

Port1 Char Format

Port1 handshaking Choose between “None” and “XonXoff”. Default option is “none”. P1 MODB slave add Port1 Modbus mode Choose between “RTU” and “ASCII”. Default mode is “RTU”. P1 Modbus byte order

P1 Modbus Features

Choose from a range of rates that go as low as 300 bits per second (bps) and as high as 19200bps. Default rate is “9600” Choose the appropriate character format that specifies the number of data bits, number of stop bits and type of parity checking. Default format is “8bits none 1stop”.

Choose the numeric MODBUS slave (base) address for the 7950. Default address is 0.

Choose between “Modbus default” and “Word swap”. Default byte order is “Modbus default”.

This enables virtual slaves and makes their data available to a MODBUS master. Available options are combinations of the words “Alarm”, “List1” and “List2”. Default option is “None”.

Page 7.6

• Port two is connected to a MODBUS network

Parameters Instructions

Comms port2 owner Select the “Modbus slave” option. Default selection is “None” Port2 Baud rates

Port2 Char Format

Port2 handshaking Choose between “None”, “XonXoff” and “CTS/RTS”.

Port2 RS232 / 485 Choose between “RS 232” or “RS 485”.

P2 MODB slave add Port2 Modbus mode Choose between “RTU” and “ASCII”. Default mode is “RTU”. P2 Modbus byte order

P2 Modbus Features

Default format is “8bits none 1stop”.

Default option is “none”.

Default signal standard is “RS 232”.

Choose the numeric MODBUS slave (base) address for the 7950. Default address is 0.

Choose between “Modbus default” and “Word swap”. Default byte order is “Modbus default”.

This enables virtual slaves and makes their data available to a MODBUS master. Available options are combinations of the words “Alarm”, “List1” and “List2”. Default option is “None”.

Chapter 7 Serial Communications and Networking

• Port three is connected to a MODBUS network

Parameters Instructions

Comms port3 owner Select the “Modbus slave” option. Default selection is “None” Port3 Baud rates

Port3 Char Format

Port3 handshaking Choose between “None”, “XonXoff” and “CTS/RTS”. Default option is “none”. Port3 RS232 / 485 Choose between “RS 232” or “RS 485”. Default signal standard is “RS 232”.

P3 MODB slave add Port3 Modbus mode Choose between “RTU” and “ASCII”. Default mode is “RTU”. P3 Modbus byte order

P3 Modbus Features

Choose the numeric MODBUS slave (base) address for the 7950. Default address is 0.

Choose between “Modbus default” and “Word swap”. Default byte order is “Modbus default”.

This enables virtual slaves and makes their data available to a MODBUS master. Available options are combinations of the words “Alarm”, “List1” and “List2”. Default option is “None”.

7.5.2. High speed list configuration

This facility allows gr oups of data locations to be kept together for easy access.

High speed list one

Step 1 Find the <“MODBus Comms list1”> sub-menu.

Step 2 Set location numbers into the pointers.

There are 20 pointers available:

Parameters

MODB DBM list1 ptr 1

: : : :

MODB DBM list1 ptr 20

High speed list two

Step 1 Find the <“MODBus Comms list2”> sub-menu.

Step 2 Set location numbers into the pointers.

There are 20 pointers available:

Parameters

MODB DBM list2 ptr 1

: : : :

MODB DBM list2 ptr 20

Page 7.7

Chapter 7 Serial communications and Networking

7.6. Database access over a MODBUS network

7.6.1. Introduction

There are three types of information that can be obt ained from the 7950 database - Data values, data states and

reply data size and type.

Examples are provided for each information type. They show the command (hexadecimal values) that needs to be

transmitted by the MODBUS master and the reply to expect from the MODBUS slave. Abbreviated meanings are

shown, under the transmission and reply lists, t o distinguish the important elements. An analysis of the response

from the 7950 is provided at the end of the example.

Abbreviation Meaning

Slv. The slave (base) address. It is 0x0A for the examples. Err. Error code. E.g. 83 = Error reading / Exception Fn. Function code. E.g. 03 = Read multiple registers Reg. Cnt Number of registers requested Reg. ID Register identification number D.C. Number of ‘data bytes’ in reply The data Data bytes that contain the useful information Chk sum Calculated checksum - always two bytes at the end

Some data locations may not be in use or may have a “No access” security attribute and, therefore, be

permanently un-available. The response from a command to read such data is of the form:

Receive 0A 83 … B1 33

Meaning Slv. Err. … Chk sum

Important note: The database construction is dependent on the software version and issue. For a full list of data locations, locate the ASCII text file with the filename extension ‘.MAN’ on your ‘FC CONFIG’ installation disk. Otherwise, contact the factory.

Page 7.8

7.6.2. Database information type 1: Data values

7950 data values are mapped within the first 10,000 MODBUS registers.

Example 1: Read Action Read MODBUS register 0717:

Transmit 0A 03 02 CD 00 02 55 37

Meaning Slv. Fn. Reg. ID Reg. Cnt. Chk sum

Receive 0A 03 04 41 C8 00 00 D5 31

Meaning Slv. Fn. D.C. The data Chk sum

Result

The data value, 0x41C8000, translates from a 32bit IEEE number into the floating point number 25.0

Example 2: Write a new value to Action Write to MODBUS register 0717:

Transmit 0A 10 02 CD 00 02 04 1B 00 00 00 04 C6

Meaning Slv. Fn. Reg. ID Reg. Cnt D.C. IEEE 32b data val. Chk sum

Result

Prime SG value changes value. The 0x1B000000, translates from a 32bit IEEE number into the floating point number 1.05879118E-22.

Example 3: Read Action Read MODBUS register 0307:

Transmit 0A 03 01 33 00 0B F4 85

Meaning Slv. Fn. Reg ID Reg Cnt. Chk sum

Receive 0A 03 16 20 … 20 30 31 31 30 00 00 6E 33

Meaning Slv. Fn. D.C The data A B X Y Chk sum

Prime SG value from location 0718

Prime SG value (location 0718)

Alarm state from location 0308

Chapter 7 Serial Communications and Networking

Result There are 22 (0x16) bytes of returned data. It is padded out with sixteen ASCII spaces (0x20).

Alarm

digit

Data

Alarm

state

A 30 ‘0’ B 31 ‘1’ X 31 ‘1’ Y 30 ‘0’

Page 7.9

Chapter 7 Serial communications and Networking

7.6.3. Database information type 2 : Data states

7950 data states (i.e. “Live”, “Set”, etc.) are mapped within MODBUS registers that range from 30001 to 40000.

Example 1: Read the default power-on status of Action Read MODBUS register 30717:

Transmit 0A 03 77 FD 00 01 0F 35

Meaning Slv. Fn. Reg. ID Reg. Cnt. Chk sum

Receive 0A 03 02 00 01 DC 45

Meaning Slv. Fn. D.C. The data Chk sum

Result The data value, 0x0001, indicates that

Example 2: Change status of Action

Prime SG value (location 0718)

Change status to ‘LIVE’ by writing 0x0000 to MODBUS register 30717:

Transmit 0A 10 77 FD 00 01 02 00 00 0F 35

Meaning Slv. Fn. Reg. ID Reg. Cnt. D.C. Data Val. Chk sum

Example 3: Read status of Action

Alarm state (location 0308)

Read MODBUS register 30307:

Transmit 0A 03 76 63 00 01 6F 27

Meaning Slv. Fn. Reg. ID Reg. Cnt. Chk sum

Receive 0A 03 02 00 FF 5D C5

Meaning Slv. Fn. D.C. The data Chk sum

Result The data value, 0x00FF, indicates that

SG Prime value has a ‘SET’ status at present.

Alarm state does not have a status.

Prime SG value (location 0718)

Page 7.10

7.6.4. Database information type 3: Reply size and type

The size and type of “data value” registers are sequentially mapped to MODBUS registers that are in the range 20001 to 29999. This information is extremely useful for determining how many registers to request.

Example 1: Read size and type of data available from register 0717 (i.e. Action Read MODBUS register 20717:

Transmit 0A 03 50 ED 00 01 63 B4

Meaning Slv. Fn. Reg. ID Reg. Cnt. Chk sum

Receive 0A 03 02 09 16 9A 1B

Meaning Slv. Fn. D.C. The data Chk sum

Result 2 bytes of data returned:

0x09 = String type 0x16 = 22 bytes of data that will be returned

Example 2: Read size and type of data available from register 0307 (i.e. Action Read MODBUS register 20307:

Transmit 0A 03 4F 53 00 01 04 44

Meaning Slv. Fn. Reg. ID Reg. Cnt. Chk sum

Receive 0A 03 02 07 04 1E 76

Meaning Slv. Fn. D.C. The data Chk sum

Result 2 bytes of data returned:

07 = Type : IEEE 32-bit floating point number 04 = Size : 4 bytes of data that will be returned. Therefore

Chapter 7 Serial Communications and Networking

Prime SG value)

Alarm state)

Reg. Cnt. Will be 00 02.

This table should be used for interpreting responses for other data locations:

Database type Database

size (bytes)

Character 1 2 1 Un-signed 8-bit integer 1 2 2 Un-signed 16-bit integer 2 2 3 Signed 16-bit integer 2 2 4 Un-signed 32-bit integer 4 4 5 Signed 32-bit integer 4 4 6 32-bit floating point number 4 4 7 64-bit floating point number 8 4 8 String 22 22 9 Option 2 2 10 Location pointer 2 2 11 Time and date 16 16 12

Page 7.11

MODBUS Size

(bytes)

Type value

Chapter 7 Serial communications and Networking

7.7. Alarm logger access over A MODBUS network

Alarm logger information is available from virtual slave one. It is not advisable to clear or accept alarms using

the front panel while the alarm log is bein g queried by a MODBUS master. Doing so, could result in the

MODBUS master having an in-correct view of the alarm log.

The example, that follows, demonstrates the correct procedure for obtaining current alarm information. Slave

one address is 0x0B for this example.

Commands are a list of hexadecimal values. These values need to be transmitted by the MODBUS master.

Replies from the MODBUS slave are also shown as hexadecimal values. Abbreviated words are shown, under

the transmission and reply lists, to distinguish the important elements. An analysis of the response from t he

7950 is provided.

Abbreviation Meaning

Slv. The slave (base) address. It is 0x0A for the examples. End String terminator Err. Error code. E.g. 83 = Error reading / Exception Fn. Function code. E.g. 03 = Read multiple registers Reg. Cnt Number of registers requested Reg. ID Register identification number D.C. Number of ‘data bytes’ in reply The data Data bytes that contain the useful information Chk sum Calculated checksum - always two bytes at the end

Step one: Find out how many alarms have been logged.

Action Read MODBUS register 1999 (quantity of registers=1):

Transmit 0B 03 07 CF 00 01

Meaning Slv. Fn. Reg. ID Reg. Cnt. Chk sum

Receive 0A 03 02 00 02

Meaning Slv. Fn. D.C. The data Chk sum

Result

Reply indicates that there are two alarms in the alarm log.

Step two: Obtain current ID for the second alarm.

(Current alarm ID’s are held in registers 1 to 30. The first entry in the alarm log is at register 0.)

Action Read MODBUS register 1 (quantity of registers=1):

Transmit 0B 03 00 01 00 01 D5 60

Meaning Slv. Fn. Reg. ID Reg. Cnt. Chk sum

Receive 0B 03 02 00 1B 60 4E

Meaning Slv. Fn. D.C. The data Chk sum

Result

Reply indicates that the unique current alarm ID is 0x001B.

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Chapter 7 Serial Communications and Networking

Step three: Set and then check current alarm ID

(This makes further alarm information available for the remaining steps)

Action Write 0x001B to MODBUS register 999 (request 1 register):

Transmit 0B 10 03 E7 00 01 02 00 1B BC 2C

Meaning Slv. Fn. Reg. ID Reg. Cnt. D.C. The data Chk sum

2 (optional)

Action Read MODBUS register 999 (request 1 register)

Transmit 0B 03 03 E7 00 01 34 D3

Meaning Slv. Fn. Reg. ID Reg. Cnt. Chk sum

Receive 0B 03 02 00 1B 60 4E

Meaning Slv. Fn. D.C. The data Chk sum

Result Current alarm ID is confirmed to be 0x001B.

Step four: Get further information about the current alarm

(To get information for another alarm, use step three with another current alarm ID)

1 (optional) - Obtain time and date

Action Read MODBUS register 1009 (quantity of registers=8):

Transmit 0B 03 03 F1 00 08 15 11

Meaning Slv. Fn. Reg ID Reg Cnt. Chk sum

Receive 0B 03 10 00 22 00 3A 00 0B 00 08 07 CD 00 0E

Meaning Slv. Fn. D.C data

Result Reply data is interpreted as follows:

0022 = 34 seconds 003A = 58 minutes 000B = 11 hours 0008 = Month of August 07CD = Year 000E = 14

. Day of month

Time and date is 11:58:34 AM, 14/08/1997

Action

2 (optional) - Obtain alarm code, qualifier, etc.

Read MODBUS register 1010 (quantity of registers=2):

Transmit 0B 03 03 F2 00 02 65 16

Meaning Slv. Fn. Reg. ID Reg. Cnt. Chk sum

Receive 0B 03 04 00 36 48 20 86 E5

Meaning Slv. Fn. D.C. The data Chk sum

Result 0036 = An alarm code

48 = Additi onal alarm text letter : ‘H’ for high limit 20 = T ype : 2 = Present, State : 0 = Pending

Page 7.13

Chapter 7 Serial communications and Networking

Notes on other results:

1. Type of alarm. 0=Off, 1=On, 2=Present

2. State of alarm. 0=Pending, 1=Accepted

Action

3 (optional) - Obtain alarm text length

Read MODBUS register 2001 (quantity of registers=1)

Transmit 0B 03 07 D0 00 01 84 2D

Meaning Slv. Fn. Reg. ID Reg. Cnt. Chk sum

Receive 0B 03 02 00 12 A0 48

Meaning Slv. Fn. D.C. The data Chk sum

Result

Alarm text length is 18 bytes (0x0012).

At present, the length returned is always 18 bytes (i.e. 9 registers). The request for 9 registers has been

assumed for command to the get the alarm text. Do not

4 (optional) - Obtain alarm text

Action

Read MODBUS register 1012 (quantity of registers=9):

Transmit 0B 03 03 F3 00 09 75 11

Meaning Slv. Fn. Reg ID Reg Cnt. Chk sum

Receive 0B 03 12 53 47 20 6C 69 6D 69 74 20 … 20 00

Meaning Slv. Fn. D.C. ‘S’ ‘G’ ‘l’ ‘I’ ‘m’ ‘I’ ‘t’ … End

Note: Checksum of reply is B9 98

assume it will always be 18 bytes.

Page 7.14

Chapter 7 Serial Communications and Networking

7.8 High speed list access over a MODBUS network

Two high speed lists can be configured (see earlier section) to make a collection of locations sequentially accessible.

High speed list one

This is addressable through virtual slave 2 (i.e. slave address+2). Twenty contiguous pointers can be set-up to make twenty locations available for this list.

This is the full MODBUS register map:

MODBUS

0 Register association table length Not allowed 1

2 : Read value … Write value …pointer 3 to 19 20 21+ Not allowed Not allowed

10000 Register association table length Not allowed 10001 Read location number for pointer 1 Not allowed - Set using menus 10002 Read location number for pointer 2 Not allowed - Set using menus

: Read location … 10020 Read location number for pointer 20 Not allowed - Set using menus

10021+ Not allowed Not allowed 20000 Type + size for register 10000 Not allowed 20001 Type & size for location (pointer 1) Not allowed 20002 Type & size for location (pointer 2) Not allowed : Type & size …. Not allowed 20020 Type & size for location (pointer 20) Not allowed 20021+ Not allowed Not allowed 30001 Read data location status (pointer 1) Write data location status (pointer 1) 30002 Read data location status (pointer 2) Write data location status (pointer 2) : Read data … Write data … 30020 Read data location status (pointer 20) Write data location status (pointer 20)

High speed list two

This is addressable through virtual slave 2 (i.e. slave address+3). Twenty contiguous pointers can be set-up to make twenty locations available for this list.

Note that the register map is identical to high speed list one.

The examples, that follow, show how to get all different types of information from the ‘high speed list’ register map.

Read value from location associated with pointer 1. Read value from location associated with pointer 2.

Read value from location associated with pointer 20.

Read (Command 3) Write (Command 16)

Write value to location associated with pointer 1 Write value to location associated with pointer 2

Write value to location associated with pointer 20

Not allowed - Set using menus

Page 7.15

Chapter 7 Serial communications and Networking

Each example shows the command as hexadecimal values. T hese are the values that should be transmitted by

the MODBUS master. Also shown is the reply to expect from the MODBUS slave. An analysis of the response

from the 7950 is provided at the end of the example.

Abbreviated meanings are shown, under the transmission and reply lists, to distinguish the important elements.

Abbreviation Meaning

Some data locations may not be in use or may have a “No access” security attribute and, therefore, be

permanently un-available. The response from a command to read such data is of the form:

Receive 0A 83 … B1 33

Meaning Slv. Err. … Chk sum

Note: Data availability is dependent on the software version and issue.

For these examples, high speed list one has been configured with

location 0756 (

Software version).

Example 1: Read location ID from first pointer Action Read MODBUS register 10001:

Transmit 0C 03 27 11 00 01 DF A6

Meaning Slv. Fn. Reg. ID Reg. Cnt. Chk sum

Receive 0C 03 02 02 F4 95 62

Meaning Slv. Fn. D.C. The data Chk sum

Result The data value, 0x2F4, indicates location 0756.

Example 2: Read data type and size value for location 0756 (through pointer 1) Action Read MODBUS register 20001:

Transmit 0C 03 4E 21 00 01 C2 35

Meaning Slv. Fn. Reg. ID Reg. Cnt. Chk sum

Receive 0C 03 02 09 16 12 1B

Meaning Slv. Fn. D.C. The data Chk sum

Result 0x09 = Type : String

0x16 = Size : 22 bytes (11 registers)

MODB DBM list2 ptr 1 (i.e pointer 1) set to

Page 7.16

Example 3: Read value from location 0756 (through point er 1) Action Read MODBUS register 1:

Transmit 0C 03 00 01 00 0B 54 D0

Meaning Slv. Fn. Reg. ID Reg. Cnt. Chk sum

Receive 0C 03 16 20 … 20 31 35 31 30 20 49

Meaning Slv. Fn. D.C. ‘1’ ‘5’ ‘1’ ‘0’ ‘I’

73 73 20 31 2E 39 30 00 00 40 AB

Meaning ‘s’ ‘s’ ‘1’ . ‘9’ ‘0’ End End Chk sum

Result

Software version string is “1510 Iss 1.90”

Example 4: Read status for location 0756 (through pointer 1) Action Read MODBUS register 30001:

Transmit 0C 03 75 31 00 01 CE D4

Meaning Slv. Fn. Reg. ID Reg. Cnt. Chk sum

Receive 0C 03 02 00 FF D5 C5

Meaning Slv. Fn. D.C. The data Chk sum

Result

0x00FF indicates that there is not status for location 0756.

Chapter 7 Serial Communications and Networking

Page 7.17

Chapter 7 Serial communications and Networking

Page 7.18

8. Alarms and Events

8.1 Alarms

8.1.1 Alarm types

The types of alarms which are detected and recorded are: System alarms, caused by one or more of:

• Power failure.

• Battery low (if a battery is fitted).

• Watchdog.

• RAM checksum failure.

• ROM checksum failure.

Input alarms, caused by one or more of:

• Failure of analogue inputs.

• Failure of density transducers.

• Incorrect data has been entered.

Chapter 8 Alarms and Events

Limit alarms, caused by one or more of:

• Limits which you have set.

• Limits defined by the system.

These always result in two alarms - one when the change first happens and another when the system returns to its normal state.

8.1.2 Alarm indicators

The 795x has three LED indicators to show alarm status; one each for Input, System and Limit Alarms. Each alarm indicator can be in one of three states:

Off The system is working normally. Flashing An alarm has been received but has not yet been accepted.

On All alarms has been acce pted but not yet cleared. The conditions that caused the alarms in the first

place may still exist.

1. System alarm 2. Input Alarm 3. Limit Alarm

Figure 8.1: Alarm indicators on the front panel

Page 8.1

Chapter 8 Alarms and Events

8.1.3 How alarms are received and stored

When a new alarm is received, the appropriate indicator LED on the front panel starts flashing. If the indicator is already flashing because of a previous alarm, it continues to do so. If the indicator is already ON (steady), it starts to flash.

Information about alarms is stored in two logs:

• The Alarm Status Display This gives: (1) a summary of the contents of the Historical Alarm Log

(2) an indication of the current status of the system.

• The Historical Alarm Log This contains an individual entry for every alarm stored in the log.

The Historical Alarm Log can store up to 30 entries. When a new alarm is received, one of two things can happen: If the Historical Alarm Log is NOT full:

An entry for the new alarm is simply added to the list.

If the Historical Alarm Log is full:

It depends on how the system is set up: Either (1) the oldest entry is deleted and the new one is added to the top of the list, or (2) the new alarm is discarded. In either case, the Status Display is updated automatically.

8.1.4 Examining the Alarm Status Display and Historical Alarm Log

Press the INFORMATION MENU (i) button If you want to examine the Alarm Status Display or Historical Alarm Log.

• To bring up the Alarm Status Display, select the Alarm Summary option.

• To bring up the first entry in the Historical Alarm Log, select the Alarm History option.

• To return to the INFORMATION MENU from the two screens , you can use the BACK button

Page 8.2

Figure 8.2: How to get to the alarm log

8.1.5 What the Alarm Status Display tells you

A typical Alarm Status Display is shown in Error! Reference source not found.. The display lists, for each type of alarm (System, Input or Limit), the number of alarms that are live and new.

• New alarms are alarms that have been received but not accepted.

• Live alarms are alarms that refer to conditions still active.

An example of a live alarm is when there is a fault in the system. This produces two alarms - one when the fault first occurs (‘ON’) and the second when it is put right (‘Off’). If only the first alarm of the pair has been received, the alarm is said to be live because the condition still exists.

The number of live alarms tells you how many faults are still active. If you look at the Historical Alarm Log this tells you more about these faults.

8.1.6 What the entries in the Historical Alarm Log tell you

Figure 8.3 shows a typical display and the function of the relevant buttons.

Key to figure:

1. Indicates if there are entries BEFORE this one

2. Alarm is either ‘ON’ (fault occurrence) or ‘OFF’ (fault cured).

3. Type of alarm

4. Indicates alarm not accepted

5. Accept this alarm

6. Alarm description and extra identifier to qualify the alarm

7. Clear this alarm entry

8. Date and time that this alarm (message) was raised.

9. Identifies a metering-run/stream - not applicable to single

meter-run/stream software

10. Indicates that there are alarm entries AFTER this one

11. Scroll DOWN through the entries

12. Scroll UP through the alarm entries

13. Clear all alarm entries.

Chapter 8 Alarms and Events

Figure 8.3: A typical entry in the log

Each alarm has its own entry in the Historical Alarm Log which tells you:

• Type of alarm Whether it is a System alarm, Input alarm or Limit alarm and if the alarm is ‘on’ or ‘off’.

• Extra identifier for the alarm This is not always shown for every entry but, where it is shown, it could be one of the following:

• A digit This indicates the channel number on which the fault occurred.

• A letter H and L are for high and low Limit alarms, S is for a step alarm.

• Date and time

The date is in the format DD-MM-YY and the time HH:MM:SS. These are entered automatically by the system when the alarm is received. The time is accurate to within one second.

Page 8.3

Chapter 8 Alarms and Events

• Acceptance indication This is only shown for those entries which have not been accepted. When the entry is accepted, the

indicator disappears.

• Other entries indication An up-arrow symbol shows that there are entries before the present one, a down-arrow symbol shows that

there are others after. If the entry currently shown is first in the list, there is no up-arrow. If it is last, there is no down-arrow.

• Description of the alarm This is an abbreviated description of the alarm and should be sufficient to help you trace the cause of the problem. A full list of all alarm messages and what they mean, are listed on page 8.3.

8.1.7 Clearing all entries in the Historical Alarm Log

To clear all the alarm entries in the Historical log, press the CLR button. This clears all entries in the Historical Alarm Log, zeroes the entries in the Status Display and sets all LED indicators to OFF.

Page 8.4

8.1.8 User-defined Alarms X and Y

Two user limit alarms, nominated as ‘X’ and ‘Y’, are available for monitoring values of measurements that do not have alarm limits.

Configuring the flow computer involves:

1. Supplying the unique identification (ID) number of the parameter to be monitored by the 795x.

2. Supplying high and low alarm limits for the parameter.

3. Nominating a status output (if requiring to indicate to an external system when the alarm is active.)

Configuration task

Follow these instructions if you want to configure a user-defined alarm (X or Y):

1. Navigate to the menu of the parameter to be monitored and then press th e ‘a’ button once to display the identification (ID) number of the parameter. Make a note of that ID number.

2. Navigate to this menu: <“Configure”>/<“Additional features”>/<“Alarms”>.

3. Select the menu for either ‘Alarm X’ or ‘Alarm Y’.

4. Locate and edit associated parameters as listed in Table 8.1.

5. The user alarm will now appear in the Historical Alarm Log when the parameter value exceeds the limits.

Also, a nominated status output will indicate if the alarm is active.

Chapter 8 Alarms and Events

Table 8.1: User-defined Alarm Parameters

Parameters * Instructions and Comments

User alarm ptrlist • Use this to select a measurement to be monitored.

• Press the ‘b’ button once.

• Use UP-ARROW or DOWN-ARROW button to scroll through a multiple-choice

list of measurements.

• Press the ‘b’ button once to confirm your selection.

User alarm hi lmt • This parameter defines the highest allowable value for the selected

measurement. A high limit alarm is raised when this upper limit is exceeded.

• Press the ‘b’ button once.

• Edit a value using the numeric keypad.

• Press the ‘b’ button once to confirm your programmed value.

User alarm lo lmt • This parameter defines the lowest allowable value for the selected

measurement. A low limit alarm is raised when this lower limit is exceeded.

• Press the ‘b’ button once.

• Edit a value using the numeric keypad.

• Press the ‘b’ button once to confirm your programmed value.

Alarm DOUT • Optional parameter is for nominating a status output to indicate the presence of

this alarm, if active in the Historical Alarm Log.

• Press the ‘b’ button once.

• Use UP-ARROW or DOWN-ARROW button to scroll through a multiple-choice

list of status outputs.

• Press the ‘b’ button once to confirm your selection.

• You may wish to change the logic of the output. If so, navigate to the menu:

<”Configure”><”Status Output”> and edit the parameter associated with your selection.

User alarm ptr. • Use this to check which parameter has been selected. Pressing the ‘b’ button

reveals the identification number of the parameter.

* On-screen descriptions include an extra letter to identify the alarm nomination.

Page 8.5

Chapter 8 Alarms and Events

8.1.9 User-defined ‘Comparison’ limit alarm

Two user comparison alarms (nominated as ‘A’ and ‘B’) are available for comparing values of two parameters and raising an alarm when the difference is outside a ‘Set’ limit.

Configuring involves:

1. Supplying the identification numbers of the two parameters to be monitored

2. Supplying a value for the comparison limit

Configuration task

Follow these instructions if you want to configure a user-defined alarm (A or B):

1. Navigate to the menu pages of the two parameters to be compared. Use the ‘a’ button to display the parameter identification (ID) number. Make a note of each ID number.

2. Navigate to this menu: <“Configure”>/<“ Additional features”>/<“Alarms”>

3. Locate and edit parameters as shown in Table 8.2.

4. The user alarm will now appear in the Historical Alarm Log when the difference in value between the two

parameters exceed the comparison limit.

Table 8.2: User Comparison Alarm Parameters

Parameter * Instructions and Comments

Comp alarm ptr1

Comp alarm ptr2

Comp alarm limit

• Use this to select the first parameter in the comparison.

• Press the ‘b’ button once.

• Enter the ID number of the parameter.

• Press the ‘b’ button once to confirm your selection.

• Use this to select the second parameter in the comparison.

• Press the ‘b’ button once.

• Enter the ID number of the parameter.

• Press the ‘b’ button once to confirm your selection.

• This parameter defines the maximum allowed difference between values of the

two parameters without needing to raise an alarm.

• Press the ‘b’ button once.

• Edit a value using the numeric keypad.

• Press the ‘b’ button once to confirm your programmed value.

* On-screen descriptions include an extra letter to identify the alarm nomination

Summary

The up-to-date state of all user-defined alarms are shown in this menu:<“Health check”>/<“User Alarms ”>

Alarms ‘A’ and ‘B’ each have a dedicated digit:

‘0’ = Not in use/No Alarm/Alarm accepted ‘1’ = Alarm active

Page 8.6

8.1.10 Alarm Logger Output (ALO)

The Relay Output and Status Outputs 2 to 3 are dedicated to indicating the presence of active alarms. By default, the ALO is enabled and pre-configured as shown in Table 8.3.

For information on Relay Output and Digital (Status) Output connections, refer to Chapter 2. Technical information is available in Appendix ‘C’.

Output Default Function

Relay Output Status Output 2 Status Output 3

ALO Re-configuration Options

ALO use of the Relay Output and Status Outputs 2 to 3 can be re-configured at any time by changing the selected alarm grouping.

To change the alarm grouping:

Chapter 8 Alarms and Events

Table 8.3: ALO Default Set-up

• Indicate System Alarms only

• Indicate Limit Alarms only

• Indicate Input Alarms only

1. Navigate to this menu: <”Configure”>/<”Additional features”>/<”Alarms”>/<”Alarm logger”>

2. Locate parameters as identified in Table 8.4 and change the alarm grouping option to suit your

requirements. Available options are summarised in Table 8.5.

You may wish to change the logic of the outputs. If so, navigate to the menu: <”Configure”><”Status Output”> and edit the parameters associated with the outputs. Note: The software refers to the Relay Output as Status Output 1.

Table 8.4: ALO Configuration Parameters

Parameters Purpose of Configuration Parameter

Alarm output 1 Alarm output 2 Alarm output 3

• Show/Change alarm group for Relay Output

• Show/Change alarm group for Status Output 2

• Show/Change alarm group for Status Output 3

Table 8.5: Alarm Grouping Options

Option Purpose of option

None

System

Input Limit

Any

System Input

System Limit

Input Limit

• Do not indicate presence of any alarms

• Indicate System alarms only

• Indicate Input alarms only

• Indicate Limit alarms only

• Include System, Input and Limit alarms.

• Indicate System alarms and Input alarms

• Indicate System alarms and Limit alarms

• Indicate Input alarms and Limit alarms

* This does not free up the digital (status) output for another function

Page 8.7

Chapter 8 Alarms and Events

8.1.11 Alarm Message List

Alarm message Type What it means

API calc fail Input Incorrect data caused a referred density (API method) calculation to fail. Battery failed System The back-up battery has failed. Battery low System The back-up battery is low and should be replaced.

Database error System

Dyn visc calc Input Incorrect data caused a dynamic viscosity calculation to fail. Dyn visc limit Limit Limit for dynamic viscosity exceeded. Furol 122 failed Input Incorrect data caused a Saybolt Furol 122 calculation to fail. Furol 210 failed Input Incorrect data caused a Saybolt Furol 210 calculation to fail. Kin visc limit Limit Limit for kinematic viscosity exceeded. Lineden calc fail Input Incorrect data caused a line density calculation to fail. Lineden limit Limit Limit for line density exceeded. mA input failed Input An analogue input has failed. mA input no cal System An analogue input is not calibrated. mA input cal fail System The calibration has failed. The input must be re-calibrated. mA out cal fail System The calibration has failed. The output must be re-calibrated. mA output failed System An analogue output has failed. mA output no cal System An analogue output is not calibrated. Power fail System A power supply has failed or been switched off. Pressure limit Limit Limit for pressure exceeded. PRT input failed Input A PRT input has failed. PRT no cal System A PRT is not calibrated. Ref astm fail Input Incorrect data caused referred viscosity (ASTM D341 method) calculation to fail. Ref dens limit Limit Limit for referred density exceeded. Ref dens matrix Input Incorrect data caused a referred density (matrix method) calculation to fail. Ref visc limit Limit Limit for referred viscosity exceeded. Ref visc matrix Input Incorrect data caused a referred viscosity (matrix method) calculation to fail. Saybolt uni fail Input Incorrect data caused a Saybolt universal viscosity calculation to fail. SpEqu1 calc fail Input Incorrect data caused special calculation 1 to fail. SpEqu2 calc fail Input Incorrect data caused special calculation 2 to fail. SpEqu4 calc fail Input Incorrect data caused special calculation 4 to fail. TempA limit Limit Limit for temperature A exceeded. TempB limit Limit Limit for temperature B exceeded. Timeperiod error Input An error has been detected in data from a time-period input. Timeperiod failed Input A time period input has failed. Timeperiod no cal System A time period input is not calibrated. T-period cal fail System The calibration has failed. User alarm Limit Limit for user alarm have been exceeded.

Stored data has become corrupted and the 795x configuration may have reverted to the defaults. You must check this and re-configure if necessary.

Page 8.8

8.2 Events

8.2.1 Introduction to 795X events

The 795X keeps a record of important system changes in an Event Log. This is very similar, in concept, to the alarm log, but the nature of the information kept is different.

Event details that can be viewed in the event log:

• Changes to the status of pre-determined

• Changes to the value of data pre-determined data that affects calculations.

Event details that can be seen only in a printout of the event log:

• Messages from hardware diagnostics.

• Download of a configuration completed.

8.2.2 Event indicators

Unlike alarms, there are no event indicators on the front panel of the 795x.

†

data that affects calculations.

Chapter 8 Alarms and Events

8.2.3 How events are received and stored

Information about events is stored in two logs:

• Event Status Display This gives: (1) a summary of the contents of the Historical Event Log

(2) an indication of the current status of the system.

• Historical Event Log This contains an individual entry for every event stored in the log.

There is enough room, in the historical event log, to store up to 150 event records. When a new event is received, one of two things can happen:

If the event log is NOT full :

A new event record is simply added

If the event log is full :

The event configuration data, Event full action, has two options, “Replace” and “Ignore”, for determining how to deal with a new event when the event log is full. (See Table 8.6)

Table 8.6: Event Full Action - Available Options

Option

Purpose of Option

Replace Always overwrite the oldest event in the event log

Ignore Always discard a new event when the event log is full

Note: The default action is “Replace”

†

This can not be changed; the list of auditable data is fixed.

Page 8.9

Chapter 8 Alarms and Events

8.2.4 Examining the Event Summary and the Event Log

Press the INFORMATION MENU (i) button if you want to examine the Event Status Display or the Historical Event Log.

• To bring up the Event Status Display, select the Event Summary option.

• To bring up the first entry in the Historical Event Log, select the Event History option.

• To return to the INFORMATION MENU from the two screens , you can use the BACK button

Figure 8.4: How to get to the event log

8.2.5 What the Event Status Display tells you

A typical Status Display is shown in the diagram (below). It lists, for each type of event (Auto, User or Periodic) the numbers of alarms which are active and live.

• Active events are events which have been received but not yet accepted.

• Live events are events which refer to conditions which are still active.

The number of live events tells you how many of them are still active. If you look at the Historical Event Log this tells you more about these events.

Page 8.10

8.2.6 What the entries in the Historical Event Log tell you

Figure 8.5 shows a typical display and the function of the relevant buttons.

Figure 8.5: A typical entry in the Historical Event Log

Each event has its own entry in the Historical Event Log which tells you:

• Type of event Whether it is Auto, User or Periodic and on or off.

Chapter 8 Alarms and Events

Key to figure:

1. Indicates if there are entries BEFORE this one

2. Location identifier

3. Type of event

4. Indicates event not accepted

5. Accept this event

6. Event description

7. Clear this entry

8. Date and time that this event (message) was raised

9. Indicates that there are entries AFTER this one

10. Scroll DOWN through the entries

11. Scroll UP through the entries

12. Clear all event entries.

Type What it means

Auto Changes made by the 795x application software. User Changes made by the keypad or done over serial communications.

Periodic This event type is not used at present.

• Date and time The date is in the format DD-MM-YY and the time HH:MM:SS. These are entered automatically by the

system when the alarm is received. The time is accurate to within one second.

• Acceptance indication This is only shown for those entries which have not been accepted. When the entry is accepted, the

indicator disappears.

• Other entries indication An up-arrow shows that there are entries before the present one, a down-arrow shows that there are others

after. If the entry currently shown is first in the list, there is no up-arrow. If it is last, there is no down-arrow.

• Description of the event

This is an abbreviated description of the event but should be sufficient to help you trace the reason for it. A full alarm message listing starts on page 8.8.

Page 8.11

Chapter 8 Alarms and Events

• Old value and new value Pressing the RIGHT-ARROW button displays another

screen with the old and new values of data.

Press the LEFT-ARROW (or the RIGHT-ARROW ) button for the previous display to re-appear.

8.2.7 Clearing all entries in the Historical Event Log

To clear all the event entries in the Historical Event log, press the CLR button. This clears all entries in the Historical Event Log and zeroes the entries in the Event Status Display.

Page 8.12

Chapter 9 Additional facilities

9. Additional facilities

9.1 What this chapter tells you

The 795x can process the raw data it receives from the transducers by:

• Averaging data.

You can also specify features:

• Fallback values and modes to be used if live inputs fail.

• Limits which, if exceeded, trigger alarms.

• The units in which the calculations are performed and are displayed.

• PID Control.

• Automated calibration procedures.

The following sections give more information about these, and other, topics that relate to the way in which data is processed.

9.2 Averaging data

There are several parameters whose values can be displayed as averages of whatever number of readings you specify. The parameters are:

• Line density.

• Referred density.

• 7827 Q factor.

• Line dynamic viscosity.

• Line kinematic viscosity.

• Referred viscosity.

9.3 Selecting units and data formats

You can select the units which the 795x uses for its calculations and in which it displays the data, as well as the formats in which the data is displayed.

You can choose the units and formats for:

• Density.

• Dynamic viscosity.

• Kinematic viscosity.

• Temperature.

• Pressure.

• Time.

• Fractional data.

• Saybolt universal.

• Saybolt furol.

• Speed.

• General (e.g. Specific gravity).

• Absolute zero.

• Atmospheric pressure.

Page 9.1

Chapter 9 Additional facilities

A full list of the units (metric and imperial) is given at the end of this chapter. Note that, if you change the units, the values are converted automatically to reflect the change.

9.4 Limits

You can set limits for some paramete rs so tha t an ala rm is genera ted if the limits are ex ceeded .

There are three types of limit:

• High limit: The hig hes t value tha t the para me ter can ha ve be fore an alarm is gene ra ted.

• Low limit: The lowest value that the parameter can have before an alarm is generated.

• Step limit: The greatest allow able step between successive values before an alarm is generated.

The parameters, and the types of limit that you can set for them, are:

• Line dynamic viscosity: high, low, and step.

• Line kinematic viscosity: high and low.

• Line density: high, low, and step.

• Line temperature: high, low, and step.

• Line pressure: high, low, and step.

• Referred viscosity: high and low.

• Referred/API density: high and low.

• Alarm X and Y: high and low.

9.5 Fallback values and modes

A fallback value is a value used as a temporary substitute for a parameter if a live input (i.e., the transducer, transmitter or wiring), which is normally used to calculate the parameter, should fail.

A fallback must have one of the following modes:

• None The system uses whatever value is available for the parameter regardless of whether or not the live input has failed.

• Last good value

• Fixed value

You can set fallback values for:

• Line dynamic viscosity.

• Line density.

• Line temperature.

• Line pressure.

The system uses, for the parameter, the last value prior to failure.

The system uses whatever fixed value you have specified for the fallback.

Page 9.2

Chapter 9 Additional facilities

9.6 Units which the 795x can display

The 795x can display data values with many different units, as listed below. However, when communicating with other devices, the data is always sent using the base units.

Base units:

Default units: • Units which the 795X displays unless you choose an alternative. Other units: • Units which you can choose instead of the default.

Note that many of the abbreviations used in the tables are defined in the glossary.

Parameter

9.7 Automated calibration procedures

9.7.1 Covimat - Static Zero Calibration (in air)

This procedure is activated from the front panel menu. It can allow the 795x to fully compensate for the Covimat Viscosity (mA input) signal not being a 0 percent value at 0 RPM.

What to do

Follow the configuration task list (below) and then perform the calibration procedure (on page 9.4).

Configuration task Objectives: Set-up 1 off analogue input, 1 off analogue output and Covimat details.

Follow these instructions:

1. Ensure that cabling between the Covimat and the 795x has been completed. Make sure that the DIP switch on the processor board is set for Analogue Input 1 to accept mA signals.

2. Set-up a mA input for live measurements from the Covimat. (a) Navigate to the menu: <“Configure”>/<“Inputs setup”>/<“Analog inputs”> (b) Select the sub-menu that corresponds to the analogue input being used by the Covimat. (c) Proceed through Table 9.1.

3. Set-up a mA output for controlling the required rotational speed (RPM). (a) Navigate to the menu: <“Configure”>/<“mA outputs”> (b) Select the sub-menu that corresponds to the analogue output being used by the Covimat. (c) Proceed through Table 9.2.

4. Set-up the Covimat details that are used by the calibration procedure. (a) Navigate to the menu: <“Configure”>/<“Transducer Details”>/<“Covimat”>/<“Profiling”> (b) Proceed through Table 9.3 (on page 9.5.)

Calibration Procedure Instructions

Note: The word “Fail” appears instead of “Live” when there is no mA signal being received by the 795x

through that input. After correcting the problem, change the status to “Live” again.

Objective: Apply static zero calibration procedure. Follow these instructions:

1. Navigate to this menu: <“Configure”>/<“Transducer Details”>/<“Covimat”>

2. Locate the menu-based parameter <“Covimat on-line cal.”>

3. Select “Cal. static zero” from the multiple-choice list.

The 795x will now perform the procedure (7 steps), without the need for any user interaction:

Step 1 Switches off the automated speed control sequence. (A delay is allowed for the Covimat to halt if it is

rotating.)

Step 2 Adjusts the rotation speed to 0 RPM. Step 3 Pauses for a number of seconds for the Covimat to stop rotating.

The exact timing is determined by the sum of target cycle time (a location value) and 5 seconds.

Page 9.4

Chapter 9 Additional facilities

Step 4 Checks the percentage value of the analogue input channel against fixed limits.

A percentage value that is outside the range of 0% to 4.1% (at 0 RPM) can not be compensated for and quickly results in the calibration procedure failing. An on-screen message confirms the failure and requests a keypad press to resume normal operations.

This situation may indicate that the 795x analogue input is in need of calibration. Checks need to be made on the cabling and the 795x configuration.

Step 5 Records the percentage value in the <“Covimat static zero”> parameter. This parameter is used to

offset live viscosity measurements from the Covimat.

Step 6 Changes the status of the <“Covimat rotat. zero”> parameter to “Live”.

Step 7 Displays on-screen message to indicate success and the requirement for a keypa d press to resume

normal operations, including restoration of the original rotation speed.

No other activities take place in the 795x during this procedure.

Table 9.1: Analog Input Parameters

Parameters * Instructions and Comments

Analog input type • Select “4-20mA input” from the multiple-choice list.

Analog input • Change the status to be “Live”.

* On-screen names include a number to identify the analogue input.

Table 9.2: Analog Output Parameters

Parameters * Instructions and Comments

Output selection • Select “Covimat RPM” from the multiple-choice list.

O/P eng unit @ 20mA

O/P eng unit @0/4mA

O/P 0-20 or 4-20mA • Select “0-20mA” from the multiple-choice list.

mA output filter • Select “Oversampling” from the multiple-choice list.

Analog output • Change the status to be “Live”.

• Programme (SET) a value for the highest speed that is supported by the Covimat.

• Programme (SET) a value for the slowest speed that us supported by the Covimat.

rotational

* On-screen names include a number to identify the analogue output.

Table 9.3: Covimat 105 Parameters

Parameters Instructions and Comments

Covimat step delay

• Select the time delay that will occur before the 795x will apply a new rotational speed requirement.

• Note: This location is also used for the 795x to cause delays between the application of rotational speeds that can be set-up in a list for an automated speed control sequence.

Page 9.5

Chapter 9 Additional facilities

9.7.2 7826 Liquid Density Transducer

Automated In-line Calibration (with a liquid)

This procedure is activated from the front panel menu. It allows the 795X to calculate K0 and K2 factors for a new liquid product.

Important Notice

A full explanation for “in-line” calibration can be found in the technical manual that was supplied for the 7826 transducer. It is advisable to review the relevant sections in that manual before attempting to set-up and use the 795x for this calibration procedure.

What to do

Follow the configuration task list (below) and then perform the calibration procedure (o n page 9.7).

Configuration task Objectives:

• Set-up a time perio d inp ut (de nsity transducer input).

• Set-up 7826 calibration details.

Follow these instructions:

1. Ensure that cabling between the 7826 and the 795x has been completed.

2. Ensure that a temperature channel (A to K)

3. Navigate to the top-level menu: <”Density”>

4. Locate the ‘density temperature source’ parameter and select the fluid temperature input.

5. Set-up a time period input for live measurements from the 7826.

(a) Navigate to the menu: <“Configure”>/<“Inputs setup”>/<“Time period inputs”> (b) Select the sub-menu that corresponds to the Density Input being used by the 7826. (c) Proceed through Table 9.4.

Note: The word “Fail” appears instead of “Live” when there is no frequency signal being received by the

795x through that input. After correcting the problem, change the status to “Live” again.

6. Set-up the 7826 details that are used by the calibration procedure. (a) Navigate to the menu: <“Configure”>/<“Line Density”>/<“Corrections”>

(b) Locate the paramter <”Dens corrections”> and then select “VOS” from the multiple-choice lists. (c) Navigate to the menu: <“Configure”>/<“Transducer Details”>/<“Densitometer”> (d) Proceed through Table 9.5.

Page 9.6

Chapter 9 Additional facilities

Table 9.4: Time Period Input Parameters

Time period type Time period Input (A)

Parameters * Instructions and Comments

7826 cal liq dens • Programme (SET) a density value for the calibrating fluid. Line density dDL • Programme (SET) a density offset value for the calibrating fluid.

Time period in air } Transducer K1 } Values for these parameters are located on the calibration Transducer K18 } certificate that has the same serial number as the 7826. Transducer K19 }

* Abbreviations used: “cal” = calibrated, “liq” = liquid, “dens” = density

Calibration Procedure Instructions

Parameters *

• Select the “Density” option

• Change status to be “Live”.

Instructions and Comments

* On-screen names include a number to identify the time period input

Table 9.5: Density Transducer Parameters

This information is required for graphical VOS correction method.

Objective: Apply 7826 calibration procedure. Follow these instructions:

1. Navigate to the menu: <”Configure”>/<”Transducer Details”>/<“Densitometer”>/<”7826 on-l ine cal.”>.

2. Locate the parameter <”7826 on-line cal“>

3. Select “Start calibration” from the multiple-choice list of options.

The 795x will now perform the procedure (4 steps), with the need for some user interaction:

Step 1 At the first prompt, choose “Yes” by pressing the appropriate lettered-button.

Step 2 At the second prompt, choose either the “Graphical” solution or “Analytical” solution by pressing the

appropriate lettered-button.

Step 3 At the final prompt, press any button to let the 795x continue as normal.

Step 4 Check new values of K0 and K1.

(They are located within the following menu: <“Configure”>/<“Transducer Details”>/<“Densitometer”>)

No other activities take place in the 795x during this procedure.

Page 9.7

Chapter 9 Additional facilities

9.8 Feature: PID Control

Proportional-Integral-Derivative (PID) is a control algorithm for efficiently attaining and then maintaining a LIVE measurement parameter at a user-supplied target (or ‘set-point’) value. PID control is available for controlling up to four measurement parameters.

WARNING! EXPERT KNOWLEDGE OF PID IS ESSENTIAL TO MAKE USE OF THIS FEATURE

9.8.1 Overview

Closed-loop PID Control

The implemented PID algorithm will continuously check on the difference between a target (‘set-point’) measurement value and the latest LIVE value of a nominated measurement. Whenever the difference is unacceptable, an adjustment – to narrow the difference - is derived from a three-term equation, as seen below.

A calculated adjustment value – PID output value - is checked against any enabled safeguards before being made available. Once the PID output value is freely available, it can be transmitted to an external system through any analogue output. That action should result a process change to narrow the difference. This routine is repeated every cycle until the difference is within acceptable limits.

∑

(

)

⎛

mi K ei T K ek

(

)

⎜

=+ +

** * 1

(

)

⎜ ⎝

⎛

⎞

ei ei

−−

⎜ ⎝

()(

⎟

(

⎠

⎞ ⎟

)

⎟ ⎠

Proportional

Term

Where:

()

im = Control output (for steering measurement towards a set-point)

{Parameter: <“PID Output”>}

K = Proportional gain factor

K = Integral time constant (‘Reset’ rate)

K = Derivative time constant

()

ie = Difference between set-point and measurement (i.e. the ‘error’) at cycle i

(

()

ke = The error over k cycles for 0 ≤ k ≤ i

T = Elapsed time since measurement valu e last sampled for PID algorithm {No Parameter}

{Parameter: <“PID Gain”>}

{Parameter: <“PID Integral act”>}

{Parameter: <“PID Derivative act”>}

{No Parameter}

1ie −

)

= Difference between set-point and measurement (i.e. the ‘error’) from previous cycle

{No Parameter}

Notes: (1) Variables

(2) In practice, the first order difference term, (e(i) - e(i-1)), is very susceptible to noise

problems. In most practical systems this term is replaced by the more stable, higher order equation:

Integral

Term

K , iK anddK can be edited through pages within the 795x menu system.

e = ( e(i) + 3*e(i-1) - 3*e(i-2) - e(i-3) ) / 6

Deriviative

Term

Page 9.8

Open-loop PID Control

With this method, the aim is for the PID output value itself to be driven towards a user-supplied target (set-point) output value. The measurement ‘set-point’ has no purpose.

Whenever there is a calculated difference, an adjustment – to narrow the difference - is derived from the threeterm equation seen earlier. However, the calculated ‘error’ terms are based on the difference between the “LIVE” PID output value and a “SET” target (user) PID output value.

The calculated adjustment value – PID output value - is checked against two safeguards before being made available. Once the PID output value is freely available, it can be transmitted to an external system through any analogue output. That action should result a process change to gradually narrow the difference. This routine is repeated every cycle until the difference is within acceptable limits.

9.8.2 Configuration details

Instructions:

1. Set-up the “LIVE” measurement that is to be controlled

• All the configuration reference pages for measurements are located in Chapter 11.

• Ensure that the location identification number

2. Set-up PID control

• Review the schematic (Figure 9.1) in conjunction with the associated parameters (Table 9.6)

• Navigate to this menu: <”Configure”>/<”PID Control”> and then work through all the associated

parameters, setting values and selecting options as necessary.

• Check on the idle system time to see if the cycle time needs to be increased. [MENU: <”Time”>]

3. Configure a live analogue output to transmit a PID output value

Chapter 9 Additional facilities

of the measurement (to be controlled) is noted

During every machine cycle, the analogue output will need to transmit a PID output value to whatever external system can initiate a process change (e.g. a valve controller increasing flow).

The PID output value is either:

• an adjustment for the “LIVE” measurement to reach a target (set-point) measurement value or

• an adjustment for the PID output value itself to reach a target (set-point) value, also indirectly

affecting the “LIVE” measurement. [Note: The measurement set-point is not

used in this case]

A guide to the analogue output parameters is listed in Table 9.7 (on page 9.10.)

Figure 9.1: PID Control - Schematic of Blocks and Parameters

Status check

decides the

set-point used

SETPOINT

(for measurement)

"LIVE" MEASUREMENT

This number can be found by examining the ‘.man’ text file that is present on the media of the FC-Config PC tool. The ‘.man’ file is

unique for every software release. Contact the factory if you require a copy of the file and/or FC-Config. Alternatively, locate the data page within the menu system and then use the ‘a’-button to toggle the display of the number on or off.

SETPOINT

(for PID output)

OR12

Calculate

'Error'

5 6 7

PID

Algorithm

8 9

PID

Output

10 11

ARW Limit

Check

PID

Output

13 14

Check

Ramp Limit

"LIVE"

Adjustment

Value (%)

mA Output

Page 9.9

Chapter 9 Additional facilities

Index Parameters Default Setting Notes?

Table 9.6: PID Control Parameters

- PID Enable “Disable” 1 PID Setpoint ptr (“PID Setpoint”) A 2 PID Setpoint 0.0 (A) 3 PID Input ptr 0000 (“Off”) B 4 PID Error type “Single error” C 5 PID G a in 0.0 6 PID Integral act 0.0 7 PID Der ivi ative act 0.0 8 PID Range max 0.0

9 PID Range min 0.0 10 PID ARW “Disable” D 11 PID ARW HI limit 0.0 (%) (D) 12 PID ARW LO limit 0.0 (%) (D) 13 PID Ramp limit “Ramp limit off” E 14 PID Ramp Gradient 5.0 (%) (E) 15 16

PID Output PID User Output

* shows data that can be “Live” or “Set”

0.0 F:1, G

0.0 F:2, G

Table 9.7: Analogue Output '1' Parameters (Guide for PID Control Set-up)

Parameters

(as displayed)

mA output 1 ptr list “User”

mA 1 param val @100% (<”PID Range max”> Value)

mA 1 param val @0% (<”PID Range min”> Value)

mA output 1 type (4-20mA or 0-20mA)

mA output 1 source (<”PID Output”>) mA output 1 value *

Analogue Output ‘1’ has been used here as a guide to setting-up

Example Value or

Option Setting

(LIVE Value)

• Essential option

• See

• Select suitable mA range

• ID for <”PID Output”>

• Values from <”PID Output”>

Comments

Table 9.6 Table 9.6

Notes: (for Table 9.6)

A By default, this configuration parameter is usually programmed with the database location ID of the parameter <“PID

Setpoint”>. However, any database location with a floating-point value could be identified - programmed in - as the parameter supplying the set-point (target) value.

An input alarm is raised if the ‘value’ of the identified

‘set-point’ parameter is not a floating-point value. PID control is

then temporarily deactivated until the alarm is clearable when a more suitable parameter is identified.

B This configuration parameter must be programmed with the database location ID of the measurement parameter that

is to be controlled. It must

be a parameter with a floating-point value.

An input alarm is raised if the ‘value’ attribute of the measurement parameter is not a floating-point data type. PID is then temporarily deactivated until the alarm is clearable when a suitable parameter is identified.

Page 9.10

Chapter 9 Additional facilities

(Notes continued…)

C The “Simple Error” option will calculate the ‘error’ as simply the difference between the setpoint value and

the measurement value. However, the “Complex Error” option will provide a more stable ‘error’ value. The error is derived from the following expression:

Δe = (e(i) + 3*e(i-1) - 3*e(i-2) - e(i-3) ) / 6

D Safeguard feature. See Section 9.8.4 on page 9.12.

E Safeguard feature. See Section 9.8.3 on page 9.11.

F:1 For the closed-loop method you must

change the status of <”PID Output”> and <”PID User Output”> to

both be “Live”. Calculated adjustment values will then be displayed by both parameters.

F:2 For the open-loop method you need to SET a value for the <”PID User Output”> parameter. The status of

the <”

PID Output”> parameter must be “LIVE”.

G Set-up any analogue output to transmit a value of the <”

PID Output”> parameter. This database location

ID is 1288. Configure the analogue output to utilise the ‘user parameter’ option. Refer to Chapter 11 for applicable configuration reference pages. Analogue output connections are as guided in Chapter 2.

9.8.3 Ramp-limit Safeguard

Many systems implement a limiter on the maximum rate of change to the PID output value. This has a similar effect to an engine rev-limiting device. However, this PID safeguard prevents physical devices from being damaged through unnecessary adjustments.

The ramp-limit is specified in degrees, representing the angle the output makes with the horizontal on a graph. The time axis resolution is therefore critical to the significance of this parameter. A limit of zero degrees would make output ramping impossible and a limit of 90 degrees or greater would allo w maximum ramping.

With the open-loop PID control method, the ramp-limit checks are mandatory and are applied every cycle. However, programming a zero degree angle will inhibit this safeguard.

PID Ouput (%)

X1< Y

Time

< Y

PID Output

(Tangent)

Ramp Limit

Gradient

PID Output

(Angle)

Ramp Limit

(Angle)

Page 9.11

Chapter 9 Additional facilities

9.8.4 Anti-Reset-Windup Safeguard

Practical systems stop the summation of error terms if the PID output value is outside a user-specified boundary. This limiting of the error summation is commonly referred to as Anti-reset-windup (ARW). When ARW is enabled, ARW limiting is applied to every output value from the PID calculation before it is saved in the 795x database. The ARW limit boundary is specified as a low and high percentage of the full-scale (maximum) PID output value.

With the open-loop PID control method, the ARW boundary checks are mandatory and are applied every cycle. However, a zero percent boundary will inhibit ARW limiting.

Figure 9.2 demonstrates ARW in action, complemented with example settings as shown in Table 9.8.

Figure 9.2: Anti-reset-windup (ARW) in action

PID OUTPUT varying

as process changes

HIGH

ARW Boundary

LOW

100

HIGH

ARW Boundary

LOW

PID OUTPUT (%)

ARW is limiting output %

(e.g. minimum flow)

Process change

(e.g. Pump failure)

Process change

(e.g. pump fixed)

ARW is limiting output %

(e.g. maximum flow)

TIME

Table 9.8: ARW Associated Parameters

Parameters ** Example Setting Comment

PID Range max 100.0 • The maximum – full-scale - PID output value

PID Range min 0.0 • The minimum allowed PID output value

PID ARW “Enable” • Activate ARW boundary checking

PID ARW HI limit 100.0 (%) • % of <PID max range> for upper ARW boundary

PID ARW LO limit 0.0 (%) • % of <PID max range> for lower ARW boundary

PID Output * (“Live” Value) • “LIVE” Adjustment value (%) for the mA output

* shows data that can be “Live” or “Set”

** Parameters are located within this menu: <”Configure”>/<”PID control”>

Page 9.12

10. Configuring with wizards

10.1 Introduction to wizards

We recommend that you use Wizards to configure the 795x for your installation. They are easy to use and will guide a user through all the critical data locations and decisions that are required to satisfy the requirements of a measurement task.

There are individual Wizards available for each measurement task. For example there is a “Pressure” W izard for configuring just line pressure.

To fully configure a 795X, it is very likely that several measurement tasks are required and, therefore, several Wizards will need to be used. It is often more efficient to use a “full set-up” Wizard. This guides users through setting up more than measurement task.

Section 10.3 has a “Quick-view” guide (table) for finding out what wizards are available and what can be achieved with them.

Section 10.4 features a special wizard for selecting a standard for units of measurement.

Chapter 10 Configuring with wizards

10.2 Using wizards

Although Wizards are easy to use, some preparation is still required. Use the following check-list to prepare. Ensure that:

• All physical connections to the rear panel have been completed.

If this is not the case, refer to Chapter 2 (Getting Started) and Chapter 3 (About the 7950) for details of supported connections.

• Front panel keyboard buttons and the menu system are familiar.

Chapters 5 and 6 are provided to assist with this. It might be a good idea to bookmark the summary of buttons in Chapter 5 for quick reference.

• Identification numbers of important result data are written down.

These numbers will be required for configuring facilities such as analogue outputs. There are two ways to find out data location numbers:

(1) Examine the “.man” file that is supplied on the FC-Config (2) Locate the data within the menu system and then press the ‘a’-button to display the unique

identification number on line 4. (Pressing the ‘a’-button toggles the number display on or off.)

• Calibration certificates (and supporting data sheets) for all field instrumentation are availabl e.

• There is a comprehensive list of all the 795X input and output connections that are being used and a

list of the measurement tasks that are required.

media or

This number can be found by examining the ‘.man’ text file that is present on the media of the FC-Config PC tool. The ‘.man’ file is

Page 10.1

Chapter 10 Configuring with wizards

Starting a wizard from the front panel is easy. Follow these instructions:

about what line two is presently displaying.

Step 4: Press the ‘b’-button once to start the wizard selection process. Step 5: Use the DOWN-ARROW button to scroll through all available wizards (on line two). Step 6: Press the ENTER button twice to select and then start a wizard that was named is on-screen.

Once a Wizard is started, follow the prompts to supply the information it asks for and then, if necessary, use Chapter 11 and the menu system to edit the resulting configuration to match your exact needs.

Wizard interactions involve several buttons: a, b, c ,d buttons - Answer a question (e.g. “Yes” or “No”) or used for normal data location editing ENTER button - Confirm a selection or edited setting (e.g. new value), move on to next prompt < button - Go back to a previous important decision prompt.

After completing a wizard, the screen with “Setup Wizard” re-appears. Further wizards can then be selected in

the same way as before. Note that it is not necessary for the “None” option to be selected before proceeding to other 795X work.

All configuration results can be viewed in the routine operation menus (Refer to Chapter 12 for menu data maps).

Page 10.2

10.3 Quick-view Guide (Set-up Wizards)

Wizards Measurement Tasks Comments

Initialise

Reset

Liquid density 1

7827 dens/visc

Degrees API

Covimat viscosity

Setup

Temperature

Pressure

Analogue Outputs

Multi view

Comms ports

Config status

• Clear all user programming to defaults

• Clear all user programming to defaults and all other

values to zero.

• Line Density (Time Period Input 1)

• Referred Density (API or 4x5 Matrix)

• Temperature ‘A’ (Analogue Input 1)

• Line Pressure (Analogue Input 2)

• Analogue Outputs 1, 2, 4 and 4

{Line density, Referred density, Temperature ‘A’ and

Line pressure}

• Multi-view page {Line density, Referred density, Temperature ‘A’ and Line pressure}

• Line Dynamic Viscosity (Time Period Input 2, 2b)

• Line Kinematic Viscosity

• Temperature ‘A’ (Analogue Input 1)

• Line Pressure (Analogue Input 2)

• Analogue Outputs 1, 2, 4 and 4

{Line dynamic viscosity, Line kinematic viscosity, Line

density and Temperature ‘A’}

• Multi-view page {Line dynamic viscosity, Line kinematic viscosity, Line density and Temperature ‘A’}

• Degrees API (Specific Gravity and Base Density of Water)

• Line Dynamic Viscosity (Analogue Input 3)

• Line Kinematic Viscosity

• Analogue Outputs 1, 2, 4 and 4

{Covimat speed RPM, Line dynamic viscosity,

Referred viscosity and Temperature ‘A’}

• Multi-view page {Covimat speed RPM, Line dynamic viscosity,

Referred viscosity and Temperature ‘A’}

• Multiple measurement tasks

• Temperature ‘A’ (mA or RTD/PRT)

• Temperature ‘B’ (mA or RTD/PRT)

• Line pressure (mA)

• mA signal outputs

• Multi-page Multi-view (button display)

• Printer

• Modbus Slave

• Modbus Master

• ‘Control word’ location set-up

Chapter 10 Configuring with wizards

Use this with caution!!

Application Wizard #1

Application Wizard #2

Application Wizard #3

You can skip tasks. See Chapter 11

See Chapter 11 See Chapter 11 See Chapter 11 Chapter 7 is a full guide to Serial

Port Communications

Page 10.3

Chapter 10 Configuring with wizards

10.4 Units Wizard Selection

Follow these instructions to select a standard for the units of measurement:

Step 1: Press the MAIN-MENU button. Step 2: Use the DOWN-ARROW button to scroll through pages until the “Configure” option appears. Step 3: Press the lettered-button that is alongside the “Configure” option. Step 4: Press the lettered-button that is alongside this description: “Units wizard”‘ Step 5: Press the ‘b’-button once to start the selection process. Step 6: Use the DOWN-ARROW button to scroll through all available options (see map below). Step 7: Press the ENTER button twice to select the standard that is named is on-screen.

Units wizard

(Selection)

Choose option

Choosing this will not do anything. Use scroll up/down keys to move through the wizard options.

Metric

Imperial

"Metric"

"Imperial"

"SI"

Exit Wizard

Figure 10.1: Units Wizard Selection

Page 10.4

Chapter 11 Configuring without using Wizards

11. Configuring without using Wizards

The recommended way of configuring the 7950 is by using wizards, as explained in Chapter 10. However, you may use the methods given here if:

• You want to change only a part of an existing configuration, irrespective of how it was configured in the first place.

• You are experienced in using the 7950 menus.

11.1 What does configuration involve?

After you have installed the instrument and made sure that it is working, you must tell it:

• What inputs the field transmitters are connected to.

• How input data is to be processed.

• How results are to be output.

The default configuration covers a general application. However, it is usually necessary to edit this configuration to suit particular needs.

11.2 Before you start

Before you begin configuring, you must obtain the calibration certificates for all the densitometers / viscometers connected to the 7950. There are examples

A calibration certificate specifies various calibration constants that allow conversion of the output periodic time signal from the densitometer (or viscometer) into a measurement value. These calibration constants will need to be programmed into the 7950.

Important!

When using 7835, 7845, and 7847 densitometers, note that Pressure Coefficient Constants K20A, K20B, K21A, and K21B are calculated for sub-sets of the full operating pressure range, and each set is listed on the certificate (see page 11.3 for a 3-set example). Select a set that is applicable to the operating pressure range.

No new instrument calibrations should be required. The pressure coefficients are valid for liquids of all densities. If you have a calibration certificate that was issued before 15 February 2007, contact the factory for a new certificate.

If you have followed the installation procedure given in Chapter 4, the 7950 is ready to be configured. Other wise, you must make sure before continuing that:

• The DIP-switches for the Analog inputs are set as guided in Chapters 2 and 4.

• All instrumentation has been connected to the 7950.

• The instrument is powered up.

of calibration certificates on pages 11.3 to 11.4.

Page 11.1

Chapter 11 Configuring without using Wizards

11.3 What will the sections tell you

Each configuration section tells you how to configure one parameter (i.e. measur ement task). Sections have been ordered so that a structured approach to configuring can be achieved.

The format for most sections:

• (Where necessary) A schematic, which shows all the data location inputs, calculation processes and data location outputs that are involved in producing a value for the parameter.

• Full instructions and parameter checklists for configuring all the input and output data that is associated with configuring the parameter.

Instructions to find menu structures are expressed in the form: “<Menu Level 1 Option>/<Menu Level 2 Option>/.../<Menu Level n Option”.

For example, the expression <“Configure”>/<“Density”> translates into the following sequence of front panel operations:

(a) Press the MAIN-MENU button. (b) Use the DOWN-ARROW button to scroll through Menu Level 1 Options. (c) Stop when “Configure” appears on the display.

(d) Press the c-button to select “Configure”. (e) Use the DOWN-ARROW button to scroll through Menu Level 2 Options. (f) Stop when “Line density” appears on the display. (g) Press the c-button to select “Line density”.

Note: Use the UP-ARROW button to scroll back through options.

Sections about configuring “Additional features” and “Multiview” have a slightl y different format from the others because of the special nature of the topics they deal with.

Page 11.2

11.4 Configuration Guide

This section provides a checklist for following a structured approach to the configuration tasks required for an installation.

Suggested order of approach:

Tasks Page

Chapter 11 Configuring without using Wizards

Live Inputs

Temperature

Pressure Density

Viscosity

Interface Detection

• Analog Inputs

• Time Period Inputs

• Temperature Channels (A to K)

• Pressure

• Transducer measured line density

• 4x5 Matrix Referred density

• API Referred density

• Specific gravity

• Degrees Brix

• Degrees Baumé

• Percent Mass

• Percent Volume

• Degrees Twaddell

• Degrees API

• Special Equation Type 1

• 7827 measured viscosity

• Kinematic viscosity measurement

• 4x5 Matrix Reference Viscosity

• ASTM D341 Reference Viscosity

• Multi-curve ASTM Reference Viscosity

• Ignition Indexes

• Saybolt Universal Viscosity

• Saybolt Furol Viscosity

• Special Equation Type 4

• Density Zoning

11.6

11.7

11.8

11. 9

11.10

11.12

11.14

11.16

11.17

11.18

11.19

11.20

11.21

11.23

11.24

11.26

11.28

11.30

11.31

11.32

11.33

11.34

Custom Equations

Live outputs

Other Parameters 11,38

Multiview 11.41

• Custom Equations

• Analog Outputs

11.35

11.36

Page 11.3

Chapter 11 Configuring without using Wizards

Note: This is NOT the calibration certificate for your densitometer.

7835B LIQUID DENSITY METER Serial No : 356366 7835BAAFAJTAAA Cal. Date : 14MAR07 Pressure Test : 151 BARA

DENSITY CALIBRATION AT 20 DEG. C AND AT 1 BARA

DENSITY PERIODIC TIME [KG/M3] [uS]

0 1086.919 DENSITY = K0 + K1.T + K2.T**2 (Air 1086.520) 300 1209.943 K0 = -1.10786E+03 \ 600 1320.514 K1 = -2.52754E-01 } 300 - 1100 kg/m3 800 1388.922 K2 = 1.17101E-03 / 900 1421.788 1000 1453.850 1100 1485.163 K0 = -1.10439E+03 \ 1200 1515.779 K1 = -2.61778E-01 } 0 - 3000 Kg/m3 1600 1632.089 K2 = 1.17566E-03 /

TEMPERATURE COEFFICIENT DATA

Dt=D(1+K18(t-20))+K19(t-20) K18 = -1.80459E-05 K19 = 1.51725E-02

PRESSURE COEFFICIENT DATA

DP=Dt(1+K20(P-1))+K21(P-1) K20 = K20A + K20B(P-1) K21 = K21A + K21B(P-1)

RANGE ( <41 BARA) RANGE (31-71 BARA)

K20A = 1.02046E-05 K20A = 5.64682E-06 K20B = -1.38764E-06 K20B = -1.25741E-06 K21A = 1.70570E-01 K21A = 1.55537E-01 K21B = -2.75303E-03 K21B = -2.32351E-03

RANGE (61-101 BARA)

K20A = -3.58705E-06 K20B = -1.11536E-06 K21A = 1.25081E-01 K21B = -1.85495E-03

where D = Density ( Uncorrected ) Dt = Density ( Temp Corrected ) DP = Density ( Pressure Corrected ) T = Periodic Time ( uS ) t = Temperature ( DEG.C ) P = Pressure (BarA)

------------- Ref No:- LD7835/V5.0/FVA DATE : 17MAR07

CALIBRATION CERTIFICATE

Figure 11.1: An example of a calibration certificate for a density transducer

Page 11.4

Chapter 11 Configuring without using Wizards

solartron

7827ACALMT VISCOMETER

(usec)

VISCOSITY = V0 + V1.1/Q**2 + V2.1/Q**4

INSTRUMENT CHECK DATA

AIR POINT (nn C) QUALITY FACTOR

VISCOSITY CODE (for 7945V/6V) =nnnn

LOW RANGE

(n-nnn)

-n.nnnnnE+nn n.nnnnnE+nn

n.nnnnnE+nn

DENSITY = K0 + K1.TB + K2.TB**2

Dt = D( 1 + K18(t-20) ) + K19(t-20)

VISCOSITY CALIBRATION @ nn C (T-piece)

VISCOSITY

(cP)

nn nnn nnn

nnnn nnnn

nnnnn

ULTRA-LOW RANGE

V0 = V1 = V2 =

DENSITY CALIBRATION @ nn C (T-piece)

DENSITY (Kg/m)

nnn nnn

nnn nnnn nnnn

VISCOSITY CORRECTION DATA Dv = Dt + (K20 + K21.1/Q**2 + K22.1/Q**4)

MEDIUM RANGE

K20 = K21 = K22 =

where

Ref No:- xxnnnn/Vn.n

-n.nnnnnE+nn

D = Density (uncorrected) Dt = Density (temperature corrected) Dv = Density (temp and viscosity corrected) TB = Time period B (uS)

Q = Quality Factor

t = Temperature ( C)

QUALITY FACTOR

nnn.nn nnn.nn

nn.nn nn.nn nn.nn nn.nn nn.nn

(n-nnn)

-n.nnnnnE+nn n.nnnnnE+nn n.nnnnnE+nn

TIME PERIOD B

nnn.nnn

n.n

nnn.nnn air check nnn.nnn nnn.nnn nnn.nnn nnn.nnn nnn.nnn

n.nnnnnE+nn n.nnnnnE+nn

SERIAL NO CAL DATE PRESSURE TEST

MEDIUM RANGE

(nnn-nnnn)

-n.nnnnnE+nn n.nnnnnE+nn n.nnnnnE+nn

K0 = K1 = K2 =

K18 = K19 =

: nnnnnn : xxxxxxx :nnBAR

HIGH RANGE

(nnn-nnnnn)

n.nnnnnE+nn n.nnnnnE+nn

n.nnnnnE+nn

-n.nnnnnE+nn n.nnnnnE-nn n.nnnnnE-nn

-n.nnnE-nn

-n.nnnE+nn

FINAL TEST &

INSPECTION

DATE : xxxxxxx

=nnnn

LD&V_034.CDR Calibra tion cer tificate for a 7 8 27viscometer

Figure 11.2: An example of a calibration certificate for a viscosity transducer

Page 11.5

Chapter 11 Configuring without using Wizards

11.5 Live Inputs

This section is normally the first step to take after all the physical connections to the rear panel have been completed.

• Analog Inputs – See below.

• Time Period Inputs – Turn to page 11.7.

Note: To find out the quantity of inputs and outputs on your 7950, see Appendix C.

11.5.1 Analog Inputs

Analog inputs 1 Ö 4 have a dual function. A DIP-switch block on the processor board inside the 7950 must be configured for each Analog input to accept either mA signals from a loop-powered transmitter or accept PRT signals from a RTD/PT100 transmitter. Further information is provided in Chapters 2 and 4.

Extra Analog inputs have a single function. They can accept only mA signals from loop-powered transmitters.

Follow these instructions to set-up an Analog input:

1. Navigate to the menu: <“Configure”>/<“Inputs setup”>/<“Analog inputs”>.

2. Select the menu of the Analog input to be configured.

3. Proceed through Table 11.1.

4. If extra Analog inputs are available, the parameter <”Qty Ain channels”> must be programmed with the total

number of inputs available.

The <“Analog Input”> parameter supplies live values to other measurements tasks. Measurement tasks have a parameter for selecting a specific Analog channel to supply live values.

Table 11.1: Analog Input Parameters

Parameters * Instructions and Comments

Analog input type • mA? If yes, select either “4-20mA input” or “0-20mA input”.

• RTD/PT100? If yes, select “RTD/PT100 input”.

Analog Input • Change the status to be “Live”.

* On-screen names include a number to identify the Analog input.

Page 11.6

11.5.2 Time Period Inputs

A 7950 can support up to 4 time period inputs (density/viscosity transducer inputs).

Follow these instructions to set-up the input details:

1. Navigate to the menu: <“Configure”>/<“Inputs setup”>/<“Time period”>.

There are individual menus for all time period inputs.

2. Select the menu of the input to be configured.

3. Proceed through Table 11.2.

Repeat the task for each input required.

Notes

<Time Period Input a> and <Time Period Input B> are both required to be “Live” only when using by a 7827 viscosity transducer (or similar).

Density transducers require only <Time Period Input a> to be “Live”.

Chapter 11 Configuring without using Wizards

Table 11.2: Time Period Input Parameters

Parameters * Instructions and Comments

Time period type • Density transducer? If yes, select the “Density” option from a list.

• Viscosity transducer? If yes, select the “7827” option from a list.

Time period input a • Change the status to be “Live”. Time period input b • (Viscosity transducer only) Change the status to be “Live”.

* On-screen names include a number to identify the time period input.

Page 11.7

Chapter 11 Configuring without using Wizards

11.6 Temperature Channels (A to K)

This section shows how to configure up to 10 temperature measurement channels. The first channel is designated ‘A’ and the final channel is designation ‘K’.

What to do

Look at Figure 11.3 to see how data is used. Work through the configuration instructions to get the 7950 to produce the result.

Figure 11.3: Temperature Channel Blocks

Follow these instructions to set-up temperature channels:

1. Ensure that the Analog inputs are set-up (page 11.6).

2. Navigate to the menu: <“Configure”>/<“Temperature”>

3. For each applicable channel (A to K), proceed through Table 11.3.

Table 11.3: Temperature Channel Parameters

Parameters *

Temp input chl

Temperature @ 20mA

Temperature @ 0/4mA

Temp HI limit

Temp LO limit

Temp step limit

Temp fallback type

Temp fallback value

Temperature offset

Temperature

• Select the Analog input that is used by the field transmitter.

• Programme (SET) a value for the highest

by the field transmitter. (Not PRT)

• Programme (SET) a value for the lowest by the field transmitter. (Not PRT)

• Programme (SET) a value for the highest allowable temperature without having to raise a high limit alarm. **

• Programme (SET) a value for the lowest allowable temperature without having to raise a low limit alarm. **

• Programme (SET) a value for maximum difference allowed between two consecutive temperature measurements without having to raise a step limit alarm. (0 = no step limit check.)

• Select how a live input failure is to be handled.

• Programme (SET) a line temperature value to be used by a fallback mode.

• Use this for optional on-line calibration of the transmitter.

• Change the status to be “Live”.

Instructions and Comments

temperature that can be measured

* On-screen names include a channel letter (e.g. ‘A’) . Some localised menu searching is required.

Abbreviation used: “chl” = channel

** Keep high and low limits set to 0 if these limit checks are not required.

Page 11.8

11.7 Pressure

This section shows how to configure the line pressure (P) measurement task.

What to do

Look at Figure 11.4 to see how data is used to get line pressure. Work through the configuration instructions to get the 7950 to produce that result.

Chapter 11 Configuring without using Wizards

Figure 11.4: Line Pressure Blocks

Follow these instructions to set-up line pressure:

1. Ensure that the Analog inputs are set-up (page 11.6).

2. Navigate to this menu: <“Configure”>/<“Pressure”>/<”Line pressure”>

3. Proceed through Table 11.4.

Table 11.4: Line Pressure Parameters

Parameters *

Line press. inp. chl.

Press value @ 20mA

Press @ 0/4mA

Press HI limit

Press LO limit

Press step limit

Line press FB type

Line press. FB value

Line pressure

• Select the Analog input that is used by the field transmitter.

• Programme (SET) a value for the highest

by the field transmitter.

• Programme (SET) a value for the lowest the field transmitter.

• Programme (SET) a value for the highest allowable line pressure without having to raise a high limit alarm. **

• Programme (SET) a value for the lowest allowable line pressure without having to raise a low limit alarm. **

• Programme (SET) a value for maximum difference allowed between two consecutive pressure measurements without having to raise a step limit alarm. (0 = no step limit check.)

• Select how a live input failure is to be handled.

• Programme (SET) a line pressure value to be used by a fallback mode.

• Change the status to be “Live”.

Instructions and Comments

line pressure that can be measured

line pressure that can be measured by

* On-screen names may vary from those shown here. Some localised menu searching is required. Abbreviations

used: “press.” = pressure, “inp.” = input, “chl.” = channel

** Keep high and low limits set to 0 if these limit checks are not required.

Page 11.9

Chapter 11 Configuring without using Wizards

11.8 Density

This section explains how to configure the following density tasks:

• Transducer measured line density (Below)

• 4x5 Matrix Referred density (T urn to page 11. 12 for details.)

• API Referred density (Turn to page 11.14 for details.)

• Specific gravity (Turn to page 11.16 for details.)

• Degrees Brix (Turn to page 11.16 for details.)

• Degrees Baumé (Turn to page 11.17 for details.)

• Percent Mass (Turn to page 11.17 for details.)

• Percent Volume (Turn to page 11.18 for details.)

• Degrees Twaddell (Turn to page 11.18 for details.)

• Degrees API (Turn to page 11.19 for details.)

Note: Referred density is required by most of these measurement tasks.

11.8.1 Transducer measured line density

What to do

Look at Figure 11.5 to see how data is used to get line density. Work through the configuration instructions to get the 7950 to produce that result.

Note: Corrections are selectable.

Figure 11.5: Line Density Blocks

Follow these instructions to set-up live transducer density measurements:

1. Ensure that cabling between the density transducer and the 7950 has been completed. Use the top-level menu <“Health Check”> to see that the corresponding Time Period Input (page 11.7) is set-up.

2. Ensure that a temperature channel (page 11.8) is set-up; this is for correcting density for the effect of temperature. Line pressure (page 11.9) is required for density to be corrected for the effect of pressure.

3. Set-up density transducer details.

(a) Navigate to the menu: <“Configure”>/<“Transducer Details”>/<“Densitometer”> (b) Proceed through Table 11.5 on page 11.11.

4. Set-up line density details. (a) Navigate to this menu: <“Configure”>/<“Line density”>

(b) Proceed through Table 11.6 on page 11.11.

Page 11.10

Chapter 11 Configuring without using Wizards

5. (Optional) On-line adjustment of density measurement. (a) Navigate to this menu: <“Configure”>/<“Transducer Details”>/<“Densitometer”>.

(b) <Density offset> applies an addition or subtraction of a density value to the line density. (c) <Density Meter Factor> scales line density. Normally, this is set to 1.

6. (Optional) Average transducer/line density – not shown in Figure 11.5. (a) Look in the menu: <“Time”> for present setting for the number of samples required. One sample

corresponds to one machine cycle. (This parameter is common to other measurement averag ing.)

(b) Navigate to this top-level menu: <“Density”>. (c) Locate the parameter with “Av line density” and change the status to “Live”.

Transducer line density measurements can now be used by the density referral methods. Details can be found in subsequent sections.

Table 11.5: Density Transducer Details

Parameters * Instructions and Comments

Density K0 Coeff Density K1 Coeff Density K2 Coeff

Density K18 Coeff

Density K19 Coeff Density K20A Coeff Density K20B Coeff Density K21A Coeff Density K21B Coeff

Density transducer

Transducer VOS

When using 7835, 7845, and 7847 densitometers, note that Pressure Coefficient Cons tants K20A, K20B, K21A, and K21B are calculated for sub-sets of the full operating pressure range, and each set is listed on the certificate. Select a set that is applicable to the operating pressure range. No new instrument calibrations should b e required. The pressure coefficients are valid for liquids of all densities. If you have a calibration certificate that was issued before 15 February 2007, contact the factory for a new certificate.

} } } Obtain values from the calibration certificate that has the same } number as on the density transducer. } DO NOT use values from another calibration certificate. } }

} } } }

• (VOS correction only) Select the type of density transducer.

• (VOS correction only) Set a factor for the velocity of sound effect.

* Abbreviations used: “Coeff” = coefficent, “VOS” = Velocity of sound.

serial

Table 11.6: Line Density

Parameters Instructions and Comments

Density source

Dens corrections

Dens temp source

Line dens HI lmt

Line dens LO lmt

Ln dens step limit

Ln dens fallback type

Ln dens fallback val.

Line density

• Select the time period input (transducer input).

• Select the corrections to be applied to the raw density measurement.

• Temperature correction? If yes, select a temperature channel (A to K).

• Programme (SET) the highest allowable line density value without having to raise a

high limit alarm.

• Programme (SET) the lowest allowable line density value without having to raise a low limit alarm.

• Programme (SET) the highest allowable difference between two consecutive line density values without having to raise a step limit alarm.

• (Optional) Select what happens to the value of line density when there is trouble with the live input.

• (Optional) Edit a fallback value to be copied to line density when there is a fallback condition and the fallback value is required.

• Change the status to be “Live”.

* DO NOT select viscosity correction unless a 7827 viscosity transducer is being used for density measurements. **

Keep the high and low limits set to 0 for this limit check to be switched off.

Page 11.11

Chapter 11 Configuring without using Wizards

11.8.2 4x5 Matrix Referred density

The calculation of density at various reference conditions can be performed by one of two supported referral methods:

(a) 4x5 Matrix Referral – See below. (b) API Standard (Tables 53A/53B) – Turn to page 11.14 for details.

What to do Look at Figure 11.6 to see how data is used, read the overview , and follow configuration instructions.

Figure 11.6: 4x5 Matrix Referred Density Blocks

Overview of 4x5 Matrix referral method

In Figure 11.7 below, each curve shows how density varies with temperature for a different fluid or different grade of the same fluid. Each curve is defined by density values at five different temperature reference points. These temperature and density values need to be input to the 7950.

Referred density is obtained by interpolating between the two curves at ether side of a point, ‘T’. This point is established from the transducer line density value (ρ), reference temperature setting and line temperature measurement. The graph shows a close-up of this interpolation.

TEMPERATURE

ABC D

R40 R41 R42 R43

Referred

Density

R30 R31 R32 R33

R20 R21 R22 R23

R10 R11 R12 R13

Base

Density

Reference Temperature

DENSITY

Line temperature

R00 R01 R02 R03

Figure 11.7: 4x5 Matrix Graph

Page 11.12

Micro Motion Signal Converter with Liquid Software - Model 7950 Manuals & Guides

Specifications and Main Features

Frequently Asked Questions

User Manual

Contents

1. About this manual

1.1 What this manual tells you

1.2 Who should use this manual

1.3 Software version covered by this manual

2. Getting started

2.1 What this chapter tells you

2.2 What the examples show you

2.3 If you need help...

2.4 Example 1: 7950 with a 7826/35/45/47 densitometer

2.5 Example 2: 7950 with a 7827 viscometer

2.6 Output Connections

2.6.1 Relay Output

2.6.2 Digital (Status) Outputs

3. About the Micro Motion® 7950

3.1 Background

3.2 What the 7950 liquid signal converter does

3.3 Physical description of the 7950

3.4 Communications

3.5 Typical installations

3.6 Checking your software version

4. Installing the system

4.1 What this chapter tells you

4.2 Hazardous and non-hazardous environments

4.3 Installation procedure

4.4 Step 1: Drawing up a wiring schedule

4.5 Step 2: Unpacking the instrument

4.6 Step 3: Setting DIP switches

4.7 Step 4: Fitting the 7950

4.8 Step 5: Making the connections

4.9 Step 6: Earthing the instrument

4.10 Step 7: Connecting the power supply

5. The keyboard, display and indicators

5.1 What this chapter tells you

5.2 The layout of the front panel

5.3 What the display shows

5.4 How the buttons work

5.5 Using the buttons to move around the menus

5.6 Using the buttons to view stored data

5.7 Using the buttons to edit information

5.7.1 Text editing

5.7.2 Multiple-choice option selection

5.7.3 Numerical editing

5.7.4 Date and time editing

5.8 The 795x character set

5.9 LED indicators

5.10 Summary of button functions

6. The menu system

6.1 What this chapter tells you

6.2 What the menu system does

6.3 How the menu system works

7. Serial Communications and Networking

7.1. What this Chapter tells you

7.2. 7950 Communication Capabilities

7.3. MODBUS from the 7950 point of view

7.4. Connecting the 7950 to A MODBUS network

7.4.1. RS-232 connections

7.4.2. RS-485 (half duplex) connections

7.5. Configuring the 7950 to be a MODBUS slave

7.5.1. Port configuration

7.5.2. High speed list configuration

7.6. Database access over a MODBUS network

7.6.1. Introduction

7.6.2. Database information type 1: Data values

7.6.3. Database information type 2 : Data states

7.6.4. Database information type 3: Reply size and type

7.7. Alarm logger access over A MODBUS network

8. Alarms and Events

8.1 Alarms

8.1.1 Alarm types

8.1.2 Alarm indicators

8.1.3 How alarms are received and stored

8.1.4 Examining the Alarm Status Display and Historical Alarm Log

8.1.5 What the Alarm Status Display tells you

8.1.6 What the entries in the Historical Alarm Log tell you

8.1.7 Clearing all entries in the Historical Alarm Log