Partlow MIC RaPID Operating Manual

MIC 1820 /1420

1/8 & 1/4 DIN MICROBASED CONTROLLERS

WITH FUZZY RaPID™ CONTROL

OPERATORS MANUAL

FORM 3703 EDITION 1 © APRIL 1996 PRICE $10.00

Brand

Information in this installation, wiring, and operation manual is subject to change without notice. One manual is provided with each instrument at the time of shipment. Extra copies are available at the price published on the front cover.

Copyright © April 1996, The Partlow Corporation, all rights reserved. No part of this publication may be reproduced, transmitted, transcribed or stored in a retrieval system, or translated into any language in any form by any means without the written permission of the Partlow Corporation.

This is the First Edition of the MIC 1820/1420 manual. It was written and produced entirely on a desk-top-publishing system. Disk versions are available by written request to the Partlow Publications Department.

We are glad you decided to open this manual. It is written so that you can take full advantage of the features of your new MIC 1820/1420 process controller.

NOTE: It is strongly recommended that Partlow equipped applications incorporate a high or low limit protective device which will shut down the equipment at a preset process condition in order to preclude possible damage to property or products.

MIC 1820/MIC 1420 Manual Edition 12

Table of Contents

Section 1 - General Page

1.1 Product Description 5

Section 2 - Installation & Wiring

2.1 Installation & Wiring 7

2.2 Preparations for Wiring 9

2.3 Input Connections 16

2.4 Output Connections 20

Section 3 - Configuration & Operation

3.1 Operation 24

3.2 Configuration 31

3.3 Pre-Tune Mode 39

3.4 Auto-T une Mode 39

3.5 RaPID Feature 42

3.6 Manual T uning Method 42

Section 4 - Control Capability

4.1 Control Capability 44

4.2 Control Responses 44

4.3 Direct/Reverse Operation of Control Outputs 45

4.4 On-Off Control 45

4.5 Time Proportioning Control 46

4.6 Current Proportioning Control 47

4.7 Setpoint Adjustments 48

Appendices

A - Glossary of Terms 49

Figure A-1 Alarm Actuation 55 Figure A-2 Alarm Hysteresis 57 Figure A-3 Asymmetrical Band Alarm 60 Figure A-4 Proportional Band & Deadband/Overlap 62

B - Board Layout - Jumper positioning 63

Figure B-1 PCB Positions (MIC 1820) 63 Figure B-2 PCB Positions (MIC 1420) 64 Figure B-3 Output 2/Output 3 Removal (MIC 1820) 65 Figure B-4 Output 2/Output 3 Removal (MIC 1420) 66

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Appendices cont.

Figure B-5 CPU PWA 67 Figure B-6 PSU PWA with Relay or SSR Out.1 68 Figure B-7 PSU PWA with DC Output 1 69 Figure B-8 Option PWA 70

Figure B-9 CPU PW A with Remote Input Type 71 C - Hardware Definition Code 72 D - Input Range Codes/Remote Setpoint Input Codes 75 E - RaPID Control Feature/Alarm Hysteresis 77 F - Specifications 80 G - Model Number Hardware Matrix 89 H - Software Reference Sheet 90

Figures & Tables

Figure 1-1 Controller Display Illustration 6 Figure 2-1 Panel Cut-Out Dimensions 7 Figure 2-2 Main Dimensions 8 Figure 2-3 Panel Mounting the controller 9 Figure 2-4 Noise Suppression 12 Figure 2-5 Noise Suppression 12 Figure 2-6A 1/4 Din Wiring Label 14 Figure 2-6B 1/8 Din Wiring Label 15 Figure 2-7 AC Power 16 Figure 2-7A Nominal AC/DC Supply 17 Figure 2-8 Thermocouple Input 17 Figure 2-9 RTD Input 18 Figure 2-10 Volt, mV mADC Input 18 Figure 2-11 Remote Digital Connections 19 Figure 2-12 Remote Setpoint Input - V/mA/mV and Potentiometer 19 Figure 2-13 Remote Setpoint Selection 19 Figure 2-14 Dual Setpoint Selection 20 Figure 2-15 Relay Output 1 20 Figure 2-16 SSR Driver Output 1 20 Figure 2-17 mADC Output 1 21 Figure 2-18 Relay Output 2 21 Figure 2-19 SSR Driver Output 2 21 Figure 2-20 mADC Output 2 22 Figure 2-21 Relay Output 3 22 Figure 2-22 SSR Driver Output 3 22 Figure 2-23 mADC Output 3 23 Figure 4-1 Proportional Bandwidth Effect on Output 47 Table 3-1 Enable Mode Configuration Procedures 32 Table 3-2 Program Mode Configuration Procedures 32 Table 3-3 Tune Mode Configuration Procedures 35

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Product Description 1.1

1.1.1 GENERAL

This instrument is a microprocessor based single loop controller capable of measuring, displaying and controlling temperature, pressure, flow, and level from a variety of inputs. Most outputs are easily tuned using the instrument Pre-Tune and Auto-Tune, or RaPID (Response assisted PID) functions.

Control functions, alarm settings and other parameters are easily entered through the front keypad. E data loss during AC power outages.

The input is user configurable to directly connect to either thermocouple, RTD, mVDC, VDC or mADC inputs. The instrument can operate from either a 90-264 VAC, 50/60 HZ power supply, or optional 24V AC/DC power supply.

1.1.2 DISPLAYS

Each instrument is provided with dual displays and status indicators as shown in Figure 1-1. The upper display (RED) displays the value of the process variable. The lower display (GREEN) displays the setpoint value. Status indication is as shown, see Figure 1-1, page 6.

Technology (100 year life) protects against

1.1.3 CONTROL

The instrument can be programmed for on-off, time proportioning, or current proportioning control implementations depending on the model number. A second control output is an available option. Proportional control implementations are provided with fully programmable PID parameters.

1.1.4 ALARMS

Alarm indication is standard on all instruments. Up to two alarm outputs are possible. Alarm type may be set as Process Direct or Reverse (high or low), Deviation Direct or Reverse (above or below setpoint), Deviation Band Type (closed or open within band), or Loop Reverse or Direct. Alarm status is indicated by LED. An Alarm Inhibit is provided to prevent, when activated, unwanted alarms during power-up.

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FIGURE 1-1

Keys and Indicators

1.1.5 PROCESS VARIABLE/SETPOINT VALUE RE-TRANSMISSION OUTPUT

If the instrument is specified with this option, this output may be scaled over any desired range and re-transmitted.

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Installation and Wiring 2.1

Electrical code requirements and safety standards should be observed and installation performed by qualified personnel.

The electronic components of the instrument may be removed from the housing during installation. To remove the components, grip the side edges of the front panel and pull the instrument forward. During re-installation, the vertically mounted circuit boards should be properly aligned in the housing.

Ensure that the instrument is correctly orientated. A stop will operate if an attempt is made to insert the instrument incorrectly.

Recommended panel opening sizes are illustrated in Figure 2-1. After the opening is properly cut, insert the instrument into the panel opening. Ensure that the panel gasket is not distorted and that the instrument is positioned squarely against the panel. Slide the mounting clamp into place on the instrument (see Figure 2-3, page 8) and push it forward until it is firmly in contact with the rear face of the mounting panel.

Note: The mounting clamp tongues may engage either on the sides or the top/bottom of the instrument housing. Therefore, when installing several instruments side-by-side in one cut out, use the ratchets on the top/bottom faces.

FIGURE 2-1

Panel Cut-Out Dimensions

92 mm +0.5 - 0.00

(3.62”+.020 - .000)

PANEL CUTOUT SIZE

92 mm + 0.5 - 0.0

(3.62” + .020 - .000)

45 mm +0.5 - 0.0

(1.77" +.020 - .000)

PANEL CUTOUT SIZE

92 mm +0.05 - 0.0

(3.62”+.020 -.000

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FIGURE 2-2

Main Dimensions MIC 1420

100 mm (3.94 in.)

96 mm (3.78 in)

Side View

MIC 1820

96 mm (3.78 in.)

10 mm (0.39 in.)

Max. Panel thickness 6.0mm (.25 in)

100 mm (3.94 in.)

96 mm (3.78 in)

48 mm (1.89 in.)

MIC 1820/MIC 1420 Manual Edition 18

10 mm (0.39 in.)

Max. Panel Thickness 6.0mm (.25 in)

Side View

FIGURE 2-3

Panel Mounting the Controller

Mounting Clamp

Controller Housing

Tongues on mounting clamp engage in ratchet slots on controller housing

Preparation for Wiring 2.2

2.2.1 WIRING GUIDELINES

Electrical noise is a phenomenon typical of industrial environments. The following are guidelines that must be followed to minimize the effect of noise upon any instrumentation.

2.2.1.1 INSTALLATION CONSIDERATIONS

Listed below are some of the common sources of electrical noise in the industrial environment:

• Ignition Transformers

• Arc Welders

• Mechanical contact relay(s)

• Solenoids Before using any instrument near the device listed, the instructions below

should be followed:

MIC 1820/MIC 1420 ManualEdition 1 9

1. If the instrument is to be mounted in the same panel as any of the

listed devices, separate them by the largest distance possible. For

maximum electrical noise reduction, the noise generating devices

should be mounted in a separate enclosure.

2. If possible, eliminate mechanical contact relay(s) and replace with

solid state relays. If a mechanical relay being powered by an

instrument output device cannot be replaced, a solid state relay can

be used to isolate the instrument.

3. A separate isolation transformer to feed only instrumentation should

be considered. The transformer can isolate the instrument from noise

found on the AC power input.

4. If the instrument is being installed on existing equipment, the wiring in

the area should be checked to insure that good wiring practices have

been followed.

2.2.1.2 AC POWER WIRING

Neutral (For 115 VAC) It is good practice to assure that the AC neutral is at or near ground potential. To verify this, a voltmeter check between neutral and ground should be done. On the AC range, the reading should not be more than 50 millivolts. If it is greater than this amount, the secondary of this AC transformer supplying the instrument should be checked by an electrician. A proper neutral will help ensure maximum performance from the instrument.

2.2.1.3 WIRE ISOLATION

Four voltage levels of input and output wiring may be used with the unit:

• Analog input or output (i.e. thermocouple, RTD, VDC, mVDC, or mADC)

• SPDT Relays

• SSR driver outputs

• AC power The only wires that should run together are those of the same category. If

they need to be run parallel with any of the other lines, maintain a minimum 6 inch space between the wires. If wires must cross each other, do so at 90 degrees. This will minimize the contact with each other and reduces “cross talk”. “Cross Talk” is due to the EMF (Electro Magnetic Flux) emitted by a wire as current passes through it. This EMF can be picked up by other wires running in the same bundle or conduit.

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In applications where a High Voltage Transformer is used (i.e. ignition systems) the secondary of the transformer should be isolated from all other cables.

This instrument has been designed to operate in noisy environments, however, in some cases even with proper wiring it may be necessary to suppress the noise at its source.

2.2.1.4 USE OF SHIELDED CABLE

Shielded cable helps eliminate electrical noise being induced on the wires. All analog signals should be run with shielded cable. Connection lead length should be kept as short as possible, keeping the wires protected by the shielding. The shield should be grounded at one end only. The preferred grounding location is the sensor, transmitter or transducer.

2.2.1.5 NOISE SUPPRESSION AT THE SOURCE

Usually when good wiring practices are followed no further noise protection is necessary. Sometimes in severe electrical environments, the amount of noise is so great that it has to be suppressed at the source. Many manufacturers of relays, contactors, etc. supply “surge suppressors” which mount on the noise source.

For those devices that do not have surge suppressors supplied, RC (resistance-capacitance) networks and/or MOV (metal oxide varistors) may be added.

Inductive Coils - MOV’s are recommended for transient suppression in inductive coils connected in parallel and as close as possible to the coil. See Figure 2-4. Additional protection may be provided by adding an RC network across the MOV.

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FIGURE 2-4

0.5 mfd 1000V

220

Coil

ohms

115V 1/4W 230V 1W

Contacts - Arcing may occur across contacts when the contact opens and closes. This results in electrical noise as well as damage to the contacts. Connecting a RC network properly sized can eliminate this arc.

For circuits up to 3 amps, a combination of a 47 ohm resistor and 0.1 microfarad capacitor (1000 volts) is recommended. For circuits from 3 to 5 amps, connect 2 of these in parallel. See Figure 2-5, below.

FIGURE 2-5

MOV

R C

MIC 1820/MIC 1420 Manual Edition 112

Inductive Coil

2.2.2 SENSOR PLACEMENT (Thermocouple or RTD)

Two wire RTD’s should be used only with lead lengths less than 10 feet. If the temperature probe is to be subjected to corrosive or abrasive condi-

tions, it should be protected by the appropriate thermowell. The probe should be positioned to reflect true process temperature:

In liquid media - the most agitated area In air - the best circulated area

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FIGURE 2-6

U E E

Wiring Label 1/4 DIN

REMOTE SETPOINT SELECTION

REMOTE SETPOINT INPUT

COM V/mA/mV Pot

OUTPUT 3

Relay

N/OC

1210

N/C

SSR/DC

7 6

4 3

14 15 16 17 18 19

MAINS (LINE)

B A

RS485

COM

N/C

24V 24V

AC DC

SUPPLY

SERIAL

COMMS

D S S

Linear (mA)

UNIVERSAL

INPUT

Linear (V/mV)

RTD

Thermocouple

2 1

23 22

SSR/DC

N/O

Relay

OUTPUT 2

N/C

20 21

SSR/DC

N/O

Relay

OUTPUT 1

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1/8 DIN

REMOTE SETPOINT SELECTION

REMOTE SETPOINT INPUT

COM

V/mA/mV (Wiper)

Potentiometer

OUTPUT 3

Relay

N/OC

1210

MAINS

(LINE)

15 16 17 18

B A COM

SUPPLY

RS485

COMMS.

24 AC

DUAL SETPOINT SELECTION

SUPPLY

+ l

24V DC

SUPPLY

N/C

SSR/DC

8 7 6 5 4

UNIVERSAL

INPUT

Linear (mA)

Linear (V/mV)

T/C

RTD

3 2 1

23 22

N/O

Relay

SSR/DC

OUTPUT 2

N/C

20 21

N/C

N/O

Relay

SSR/DC

OUTPUT 1

MIC 1820/MIC 1420 ManualEdition 1 15

Input Connections 2.3

In general, all wiring connections are made to the instrument after it is installed. Avoid Electrical Shock. AC power wiring must not be connected to the source distribution panel until all wiring connection procedures are completed.

Caution: This equipment is designed for installation in an enclosure which provide adequate protection against electric shock. Local regulations regarding electrical installation should be rigidly observed. Consideration should be given to prevention of access to the power terminations by unauthorized authorized personnel. Power should be connected via a two pole isolating switch (preferably situated neat the equipment) and a 1 A fuse, as shown in Figure 2-7.

FIGURE 2-7

Main Supply The instrument will operate on 90-264V AC 50/60 Hz mains (line) supply. The power consumption is approximately 4 VA. If the instrument has relay outputs in which the contacts are to carry mains (line) voltage, it is recommended that the relay contact mains (line) supply should be switched and fused in a similar manner but should be separate from the instrument mains (line) supply .

MIC 1820/MIC 1420 Manual Edition 116

Line

Neutral

FIGURE 2-7A 24V Nominal AC/DC Supply The supply connection for the 24V AC/DC option of the instrument are as shown below . Power should be connected via a two pole isolating switch and a 315 mA slow-blow (anti-surge type T) fuse. With the 24V AC/DC supply option fitted, these terminals will accept the following supply voltage ranges:

24V (nominal) AC 50/60Hz - 20-50V 24V (nominal) DC - 22-65V

24V AC

FIGURE 2-8 Thermocouple (T/C) Input Make thermocouple connections as illustrated below. Connect the positive leg of the thermocouple to terminal 2 and the negative leg to terminal 3.

50/60Hz

24V DC

Thermocouple

MIC 1820/MIC 1420 ManualEdition 1 17

FIGURE 2-9

RTD Input Make RTD connections as illustrated below . For a three wire RTD, connect the resistive leg of RTD to terminal 1 and the common legs to terminals 2 and 3. For a two wire RTD, connect one leg to terminal 2 and the other leg to terminal 3 as shown below. A jumper wire supplied by the customer must be installed between terminals 2 and 3. Input conditioning jumper must be positioned correctly (see Appendix B) and Hardware Definition Code must be correct (See Appendix C).

RTD

FIGURE 2-10

V olt, mV Input Make volt and millivolt connections as shown below . Terminal 2 is positive and terminal 3 is negative. Input conditioning jumper must be positioned correctly (see Appendix B) and Hardware Definition Code must be correct (see Appendix C).

mADC Input Make mADC connections as shown below. Terminal 4 is positive and terminal 1 is negative. Input conditioning jumper must be positioned correctly (see Appendix B) and Hardware Definition Code must be correct (see Appendix C).

Linear (mA)

Linear (V/mV)

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FIGURE 2-11

Remote Digital Communications - RS485 Make digital communication connections as illustrated below .

COM

FIGURE 2-12

Remote Setpoint Input - V/mA/mV and Potentiometer Connections are illustrated below. Terminal 6 is positive and terminal 7 is negative. The remote setpoint input can be configured for linear DC mv, linear DC mA, linear DC Volt or potentiometer. Make sure that the input selected matches the Second Input Usage selected in the Hardware Definition Mode and the Secondary Analog Input conditioning jumper is posi-

tioned correctly (see Appendix B.)

mA/mV VOLT

FIGURE 2-13

Remote Setpoint Selection Connections are made as shown.

DRY CONTACT

Potentiometer 2 Kohms max

CONTACTS OPEN - LOCAL SETPOINT

CONTACTS CLOSED - REMOTE SETPOINT

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FIGURE 2-14

Dual Setpoint Selection

CONTACTS OPEN - SETPOINT 1 CONTACTS CLOSED - SETPOINT 2

DRY CONTACT

Output Connections 2.4

FIGURE 2-15

Relay Output 1 (Control Output 1) Connections are made to Output 1 relay as illustrated below. The contacts are rated at 2 amp resistive, 120/240 V AC.

N/C

Relay

N/O

FIGURE 2-16

SSR Driver Output 1 (Control Output 1) Connections are made to Output 1 SSR Driver as illustrated below. The solid state relay driver is a non-isolated 0-4 VDC nominal signal. Output impedance is 250 ohms.

SSR

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FIGURE 2-17

mADC Output 1 (Control Output 1) Make connections for DC Output 1 as illustrated below.

N/C

FIGURE 2-18

Relay Output 2 (Control Output 2 Connections are made to Output 2 relay as illustrated below. The contacts are rated at 2 amp resistive, 120/240 V AC.

24 23 22

OR Alarm 2)

N/O

Relay

FIGURE 2-19

SSR Driver Output 2 (Control Output 2 Connections are made to Output 2 SSR Driver as illustrated below. The solid state relay driver is a non-isolated 0-4 VDC nominal signal. Output impedance is 250 ohms.

24 23 22

OR Alarm 2)

SSR

MIC 1820/MIC 1420 ManualEdition 1 21

FIGURE 2-20

mADC Output 2 (Control Output 2) Make connections for DC Output 2 as illustrated below.

24 23 22

FIGURE 2-21

Relay Output 3 (Alarm 1) Connections are made to Output 3 relay as illustrated below. The contacts are rated at 2 amp resistive, 120/240 V AC.

Relay

10 11 12

FIGURE 2-22

SSR Driver Output 3 (Alarm 1) Connections are made to Output 3 SSR Driver as illustrated below. The solid state relay driver is a non-isolated 0-4 VDC nominal signal. Output impedance is 250 ohms.

N/OCN/C

SSR

10 11 12

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FIGURE 2-23

mADC Output 3 (Recorder Output Only) Make connections for DC output 3 as illustrated below.

10 11 12

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Operation 3.1

3.1.1 POWER UP PROCEDURE

Verify all electrical connections have been properly made before applying power to the instrument.

If the instrument is being powered for the first time, it may be desirable to disconnect the controller output connections. The instrument will be into control following the power up sequence and the output(s) may turn ON. During power up, a self-test procedure is initiated during which all LED segments in the two front panel displays appear and all LED indicators are ON. When the self-test procedure is complete, the instrument reverts to normal operation.

Note: A delay of about 3 seconds, when power is first applied, will be seen before the displays light up.

3.1.2 KEYPAD OPERATION

AUTO/MANUAL KEY This key is used to:

1. Enter the Auto/Manual mode and vice versa.

2. Used to activate the Auto Tune mode.

3. Used to confirm a change in the Program mode. SCROLL KEY

This key is used to:

1. Select adjustment of the ramping setpoint, if enabled.

2. Select a parameter to be viewed or adjusted.

3. Display enabled modes of operation.

4. Display a mode parameter value.

5. Advance display from a parameter value to the next parameter code.

6. Activate the Pre-tune mode.

7. With the DOWN key to view the current Hardware Definition Code setting.

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UP KEY This key is used to:

1. Increase the displayed parameter value.

2. Increase setpoint.

3. With the DOWN key to enter Pre and Auto Tune mode, and to engage the RaPID function.

DOWN KEY This key is used to:

1. Decrease the displayed parameter value.

2. Decrease setpoint.

3. With the UP key to enter the Pre and Auto Tune mode, and to engage the RaPID function.

4. With the SCROLL key to view the current Hardware Definition Code setting.

3.1.3 INITIAL DISPLAYS

After the instrument has performed its power up self test (during which, if the SCROLL key is held down during power up, the current instrument firmware revision is displayed), the initial Operator Mode displays appear. These are dependent upon whether the instrument is configured for single setpoint operation, dual setpoint operation or remote/local setpoint operation.

3.1.3.1 SINGLE SETPOINT OPERATION

Normally the initial displays are:

Upper Display = Process V ariable value Lower Display = Setpoint value adjustable

The setpoint may be adjusted by using the UP/DOWN keys. Press the SCROLL key again, if setpoint ramping is not disabled and if the

ramp rate is not switched OFF, to change the displays to:

Upper Display - Ramping Setpoint value ("Read Only") Lower Display = the legend SPrP

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3.1.3.2 DUAL SETPOINT OPERATION

If dual setpoint operation has been selected, the normal Operator Mode displays will be as follows:

Upper Display = Process V ariable value Lower Display = Active Setpoint value (adjustable)

Press the SCROLL key to change displays to :

Upper Display = Setpoint 1 value (adjustable)

Lower Display = the legend SP1 Press the SCROLL key again to obtain the equivalent display for Setpoint 2 (with legend SP2). NOTE: The lower display uses the left-most character to distinguish between the active and inactive setpoints in the following manner:

SP2 SP2 SP2

Active Setpoint Active Setpoint Inactive Setpoint (selected via (selected via digital input) keypad override)

Press the SCROLL key again, if setpoint ramping is not disabled and if the ramp rate is not switched OFF, to change the displays to:

3.1.3.3 REMOTE SETPOINT OPERATION

If remote setpoint operation has been selected the normal Operator Mode displays will be as follows:

Upper Display = Process V ariable value

Lower Display = Active setpoint value (Adjustable) Press the SCROLL key to change the displays to:

Upper Display = Ramping Setpoint value

Lower Display = the legend SPrP Press the SCROLL key again to obtain the equivalent display for Remote

Setpoint (with the legend rSP). NOTE: The lower display uses the left-most character to distinguish

between the active and inactive setpoints in the following manner:

SP SP rSP

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3.1.3.4 OVERRIDE FEA TURE

While the instrument is being used with either Dual Setpoint operation or Remote Setpoint operation, the Override feature is available. This enables the active setpoint selected by the digital input to be manually overridden from the keypad. To engage the Override feature, with the instrument displaying the desired setpoint (legend in lower display), press the UP and DOWN keys simultaneously. This will cause the left-most character of the lower display to show a flashing " ". This indicates that the display setpoint is now the active setpoint, regardless of the state of the digital input. To cancel an override condition, simply press the UP and DOWN keys again with this display shown.

3.1.3.5 VIEWING/ADJUSTING THE SETPOINT RAMP RATE

If setpoint ramping is enabled, the ramp rate display may be selected using the SCROLL key. The ramp rate may be adjusted (using the UP/DOWN keys) within the range 1 to 999. Any attempt to increase the value beyond 999 will cause the upper display to go blank and setpoint ramping to be switched OFF (default).

3.1.3.6 ALARM STATUS DISPLA Y*

The user may view the status of the instrument's alarm(s) by depressing the SCROLL key until the lower display shows the legend "ALSt" and the upper display shows the alarm status in the following format:

Loop Alarm Status L = Energized Blank = De-energized

Alarm 1 Status 1 = Energized Blank = De-energized

Alarm 2 Status 2 = Energized Blank = De-energized

*This display is available only if one or more of the alarms is/are energized. When "ALSt" is seen in the lower display, to enter the Program or Tune

modes, press the UP key with "ALSt" displayed, then the SCROLL key to Program or T une.

MIC 1820/MIC 1420 ManualEdition 1 27

3.1.3.7 OVER-RANGE/UNDER-RANGE DISPLA Y

If the process variable attains a value higher than the input scale maximum limit, the upper display will show:

If the process variable attains a value lower than the input scale minimum, the upper display will show:

If a break is detected in the sensor circuit, the upper display will show:

3.1.4 FRONT PANEL INDICATORS

OP1 Indicates the state of the Output 1 relay or SSR driver. When the

indicator is ON the relay is energized or the SSR driver is ON.

OP2 Indicates the state of the Output 2 relay or SSR driver. When the

indicator is ON the relay is energized or the SSR driver is ON.

ALM When flashing, indicates an Alarm condition. MAN Flashes when the Manual mode has been entered AT Indicates when the Pre-Tune, Auto-Tune or RaPID mode has been

selected; flashing RED for Pre-T une, continuously ON RED for Auto-Tune or flashing GREEN for RaPID activated.

MIC 1820/MIC 1420 Manual Edition 128

3.1.5 SETPOINT ADJUSTMENT

3.1.5.1 LOCAL SETPOINT

To adjust the instrument setpoint, proceed as follows: To adjust the Setpoint, press the UP or DOWN key as applicable.

Momentary depression will increment or decrement (as appropriate) the setpoint by one unit in the least significant digit. If the key is held for longer than 1 second, the least significant digit will change at the rate of 25 units per second. If the key is held for longer than 10 seconds, the second least significant digit will change at the rate of 25 units per second. If the key is held for more than 10 seconds, the third least significant digit will change at the rate of 25 units per second.

3.1.5.2 RAMPING SETPOINT

A selectable Ramp Rate function in the range of 1 to 9999 units per hour can be used to limit the rate at which the setpoint used by the control algorithm will change. This feature will also establish a soft start up. Upon power up, the instrument will take the initial process value as the setpoint. A setpoint ramp rate will be calculated to increase the setpoint from the initial process value to the setpoint selected. The setpoint ramp feature disables the Pre-Tune facility. The Auto-Tune facility, if selected, will commence only after the setpoint has completed the ramp.

Sudden changes in the setpoint value entered via the keypad can be inhibited from effecting the control outputs by use of this feature. The internal setpoint used to control the process will ramp to the setpoint value entered at the rate of change selected.

To view the Ramping Setpoint value while in the Control mode and "ESPr" in the Tune mode is disabled, press the SCROLL key until "SPrP" is displayed in the lower display. This is the code for the ramping setpoint value. Press the SCROLL key one more time and the lower display shows "SPrP" and the upper display will show the current ramping setpoint.

MIC 1820/MIC 1420 ManualEdition 1 29

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