Cooper Instruments DFI-250 User Manual

DFI 250

DIGITAL INDICATOR

TECHNICAL REFERENCE MANUAL

www.cooperinstruments.com

PH: (540) 349 -4746 • FAX: [phone]

CONTENTS

1.0 INTRODUCTION.......................................................................................................................................1

1.1 Overview ..................................................................................................................................................1

1.2 Approvals (for trade versions only) .....................................................................................................1

1.3 The Manuals Set.....................................................................................................................................1

1.4 Document Conventions.........................................................................................................................1

2.0 SPECIFICATIONS....................................................................................................................................2

3.0 INSTALLATION........................................................................................................................................2

3.1 Introduction.............................................................................................................................................2

3.2 General Warnings...................................................................................................................................3

3.3 Electrical Safety ......................................................................................................................................3

3.4 Cleaning ...................................................................................................................................................3

3.5 Panel Mount Template...........................................................................................................................3

3.6 Cable Connections.................................................................................................................................3

3.7 DC Power (DC PWR +, DC PWR –).......................................................................................................3

3.8 Load Cell Connection............................................................................................................................4

3.8.1 Load Cell Signals and Scale Build........................................................................................... 4

3.8.2 4-Wire Connection...................................................................................................................... 4

3.8.3 6-Wire Connection...................................................................................................................... 4

3.9 Auxiliary Connections...........................................................................................................................5

3.9.1 RS-232 Serial .............................................................................................................................. 5

3.9.2 Remote Input............................................................................................................................... 5

3.9.3 Outputs........................................................................................................................................ 6

3.10 GSE-LINK (Optional)............................................................................................................................6

3.11 Connecting Shields..............................................................................................................................7

3.11.1 Cable Shield Connection and Earthing ................................................................................. 7

3.12 Regulatory Sealing Requirements.....................................................................................................8

4.0 DATA ENTRY ............................................................................................................................................8

4.1 Editing Annunciators .............................................................................................................................8

4.2 Numeric Entry.........................................................................................................................................8

4.3 Selections and Options.........................................................................................................................9

5.0 BASIC OPERATION................................................................................................................................9

5.1 Display and Controls .............................................................................................................................9

5.1.1 Front Panel: Visual Display....................................................................................................... 9

5.2 Operation Keys.....................................................................................................................................10

5.2.1 Primary Function...................................................................................................................... 10

5.2.2 Editing Function....................................................................................................................... 10

5.3 Stability Considerations......................................................................................................................10

5.4 POWER Key..........................................................................................................................................10

5.4.1 Automatic Operation ................................................................................................................11

5.5 ZERO Key..............................................................................................................................................11

5.6 TARE Key..............................................................................................................................................11

5.7 GROSS/NET Key...................................................................................................................................11

5.7.1 GSE-LINK Activation................................................................................................................ 11

5.8 PRINT Key.............................................................................................................................................11

5.9 FUNCTION Key.....................................................................................................................................11

6.0 CONFIGURATION ISSUES..................................................................................................................12

6.1 General Setup Information..................................................................................................................12

6.2 Basic Weighing Terminology..............................................................................................................12

6.3 Filtering Techniques............................................................................................................................13

CF 147 ii version 1.1

6.4 Industrial vs. OIML and NTEP Modes................................................................................................13

6.5. Calibration Counter .............................................................................................................................13

6.6 Passwords.............................................................................................................................................14

6.6.1. Full Setup Password............................................................................................................... 14

6.6.2. Safe Setup Password.............................................................................................................. 14

6.6.3. Setup Lock-Out........................................................................................................................ 14

7.0 SETUP......................................................................................................................................................14

7.1 Accessing Setup ..................................................................................................................................14

7.1.1 Setup Display Prompts............................................................................................................ 15

7.2 Exiting Full or Safe Setup ....................................................................................................................15

7.3 Groups and Items.................................................................................................................................15

7.3.1 GRP (Group) ..............................................................................................................................15

7.3.2 ITM (Item)................................................................................................................................... 15

7.4 Setup Menus.........................................................................................................................................16

7.4.1 BUILD (Scale Build).................................................................................................................. 16

7.4.2 OPTION (Scale Options).......................................................................................................... 16

7.4.3 CAL (Scale Calibration)........................................................................................................... 17

7.4.4 SPEC (Special Settings Menu) ................................................................................................18

7.4.5 SERIAL (Serial Communications Options)........................................................................... 19

7.4.6 SET.PTS (Setpoint Settings)................................................................................................... 20

7.4.7 CLOCK (Clock Settings).......................................................................................................... 20

7.4.8 TEST (Special Test Functions) ............................................................................................... 21

7.4.9 FACTRY (Factory Adjustment Menu) .....................................................................................21

7.4.10 – End – (Leaving Setup) ........................................................................................................ 21

8.0 CALIBRATION........................................................................................................................................21

8.1 Performing a Digital Calibration with Test Weights.........................................................................22

8.1.1 ZERO (Zero Calibration Routine) ........................................................................................... 22

8.1.2 SPAN (Span Calibration Routine).......................................................................................... 22

8.2 Performing a Calibration with Direct mV/V Entry.............................................................................23

8.2.1 DIR.ZER (Direct Zero Calibration Entry)................................................................................ 23

8.2.2 DIR.SPN (Direct Span Calibration Entry) ...............................................................................23

8.3 Using Linearization..............................................................................................................................23

8.3.1 ED.LIN (Edit Linearization Points).......................................................................................... 23

8.3.2 CLR.LIN (Clear linearization) .................................................................................................. 25

9.0 SERIAL OUTPUTS .................................................................................................................................25

9.1 Automatic Weight Output....................................................................................................................25

9.2 Master Serial Output............................................................................................................................26

10.0 SETPOINTS ...........................................................................................................................................27

10.1 Setpoint Connection..........................................................................................................................27

10.2 Setpoint Operation.............................................................................................................................27

11.0 SPECIAL FUNCTIONS.......................................................................................................................27

11.1 Introduction.........................................................................................................................................27

11.2 Key Functions.....................................................................................................................................27

11.2.1 NONE....................................................................................................................................... 27

11.2.2 TEST......................................................................................................................................... 27

11.2.3 COUNT..................................................................................................................................... 27

11.2.4 UNITS....................................................................................................................................... 27

11.2.5 HOLD and PEAK HOLD ......................................................................................................... 28

11.2.6 LIVE.WT................................................................................................................................... 28

11.2.7 SHOW.T................................................................................................................................... 28

12.0 APPENDIX.............................................................................................................................................29

CF 147 iii version 1.1

12.1 Dimensions .........................................................................................................................................29

12.2 Sealing Details....................................................................................................................................30

12.3 Setup Menu Quick Reference...........................................................................................................30

12.4 Error Messages ..................................................................................................................................31

12.4.1 Weighing Errors..................................................................................................................... 31

12.4.2 Setup and Calibration Errors................................................................................................ 31

12.5 Diagnostic Errors...............................................................................................................................32

12.6 Glossary Terms ..................................................................................................................................33

13.0 WARRANTY REPAIR POLICY..........................................................................................................33

CF 147 iv version 1.1

1.0 INTRODUCTION

This instrument is a precision digital indicator using the latest Sigma -Delta A/D technology to ensure fast and
accurate weight readings.

The setup and calibration of the instrument are digital, with a non-volatile security store for all setup parameters.
The instrument may be operated from either 4 AA batteries or a DC power source from 12V to 24V. There is a soft

power on/off function that retains memory of its state. Once an instrument is turned on it will automatically start up
again if the external power is interrupted.

The instrument is fitted with GSE -LINK communications as standard. This allows a temporary isolated
communications link to be established with a PC and enables software upgrades and the use of computerized
setup and calibrat ion via the Viewer software. Refer to GSE-LINK (Optional) section 3.10 for more information.

Figure 1: Weight Indicator

1.1 Overview

This instrument provides the ZERO and TARE functionality as well as providing more setup options (e.g. serial and
setpoints) and printing functionality.

It also supports special functions (e.g. peak -hold, live weight (livestock) averaging, counting, etc.), via the user
definable <FUNCTION> key. It is equipped with an NVRAM store to ensure day -to-day operating settings (e.g.
ZERO, TARE, CLOCK, etc.), are retained when power is removed.

This instrument has two isolated transistor outputs with status display on the front panel as well as the RS -232
communications port that can be used for printer driving or connection to a remote display or PC. There is a built-in
clock for date-stamping printed outputs.

1.2 Approvals (for trade versions only)

• NSC approval (4000 divisions at 0.8µV/division).

• NMI approval (4000 divisions at 0.8µV/division).

• C-tick approved and CE approved.

1.3 The Manuals Set

This manual is part of a set of manuals covering the setup and operation of the instrument. The set includes the
following:

• Technical Reference Manual - Contains detailed information on calibration and setup. This manual is intended
for use by Scale Technicians who are installing the instrument.

• User’s Guide - Aimed at the operation of the instrument, and covers the day-to-day operation of the
instrument.

• Quick Start Manual - Intended for Scale Technicians who are familiar with the instrument and simply need a
quick reference to menu options and connection diagrams, etc.

1.4 Document Conventions

The following document conventions (typographical) are used throughout this Reference Manual.

CF 147 1 version 1.1

Bold Text Bold text denotes words and phrases to note.
<Key> <Key> denotes a Keypad key.

Note: In the Specifications section the < symbol means less than and the > symbol means greater
than.

^ This symbol denotes one space (used in Automatic Weight Output section 9.1)

Items marked with indicate that the setting is available only in Full Setup and is trade critical. When
trade critical settings are changed the calibration counter will be incremented.

2.0 SPECIFICATIONS

Performance

Resolution
Zero Cancellation ±2.0mV/V

Span Adjustment 0.1mV/V to 3.0mV/V full scale
Stability/Drift

Excitation
A/D Type 24bit Sigma Delta with 8,388,608 internal counts

A/D Conversion Rate 20Hz with FIR filtering > 80dB

Operating Environment

Case Materials ABS, Silicon Rubber, Nylon, Acrylic (no halogen used)
Packing Weights Basic Indicator: 0.75lb

Up to 30,000 divisions, minimum of 0.25µV/division, 20 updates/second
(Trade 4000 divisions at 0.8µV/division)

Zero: < 0.1µV/°C (+ 8ppm of deadload max)
Span < 8 ppm/ °C, Linearity < 20ppm, Noise < 0.2µVp-p
5 volts for up to 4 x 350 or 8 x 700 ohm load cells (4-wire or 6-wire plus shield)
Maximum total load cell resistance: 1,000 ohms

Temperature: 14 to 122°F ambient
Humidity: <90% non-condensing
Storage: –4 to 122°F ambient
IP55 when panel mounted

Digital

Display LED Backlit LCD with six 0.8” high digits with units and annunciators
Setup and Calibration Full digital with visual prompting in plain messages
Digital Filter Sliding window average from 0.1 to 4.0 seconds
Zero Range Adjustable from ±2% to ±20% of full capacity

Power Input

Standard Power Input 12 to 24VDC (2.5 VA max) - ON/OFF key with memory feature
Variants

AC Wall Transformer: 110/240VAC 50/60Hz in 12VDC 0.5A out
Battery 4 x AA batteries (Alkaline or rechargeable NiMH, NiCad, etc.)

Features

GSE-LINK Data Coupling Infra-red Connector for optional GSE-LINK PC cable (to RS-232 PC port)
Correction Five point linearity correction

Outputs
Assignable Function Key Unit switching, counting, manual hold, peak hold, live weight and totalizing

Drive Outputs 2 isolated transistor drive outputs (300mA total at 50VDC)
Battery Backed Time/Date

Clock

RS-232 automatic transmit, network or printer outputs. Transmission rate: 2400, 4800 or 9600
baud

Battery life 10 years minimum

3.0 INSTALLATION

3.1 Introduction

The following steps are required to set up the indicator.

• Inspect indicator to ensure good condition.

CF 147 2 version 1.1

• Use connection diagrams to wire up load cell, power and auxiliary cables as required.

• Use the drill hole template provided for hole locations.

• Connect Power to indicator and press <POWER> key to turn the instrument On.

• Refer to the Setup section 7.0 for information on configuring and calibrating the instrument.

• To turn instrument Off press and hold <POWER> key for three seconds (until display blanks).

3.2 General Warnings

• Indicator not to be subject to shock, excessive vibration or extremes of temperature (before or after installation).

• Inputs are protected against electrical interference, but excessive levels of electro -magnetic radiation and RFI

may affect the accuracy and stability.

• The instrument should be installed away from any sources of excessive electrical noise.

• The load cell cable is particularly sensitive to electrical noise and should be located well away from any power

or switching circuits.

• For full EMC or for RFI immunity, termination of cable shields and correct earthing of the instrument is
essential.

• Indicator and load cell cable are sensitive to excessive electrical noise. Install well away from any power or
switching circuits.

3.3 Electrical Safety

• For your protection all electrical hardware must be rated for environmental conditions of use.

• Pluggable equipment must be installed near an easily accessible power socket outlet.

• To avoid the possibility of electric shock or damage to the instrument, always switch off or isolate the

instrument from the power supply before maintenance is carried out.

3.4 Cleaning

• To maintain the instrument, never use harsh abrasive cleaners or solvents. Wipe the instrument with a soft
cloth slightly dampened with warm soapy water.

3.5 Panel Mount Template

Use the panel mount template for drill hole locations. The template indicates positions for the two 4mm mounting
screws through the panel. Also displayed on the template is the position of the rectangular hole that should be cut
to allow for the connection of cables. The drilling template supplied with the indicator allows for front or rear
machining of the panel.

3.6 Cable Connections

All cable connections are made to the rear of the instrument using screwless terminals. Wires must be stripped of
insulation by at least 10mm. To install, depress the orange lever beside the terminal required and push wire into the
hole. Release the lever and pull gently on the wire to ensure it is securely trapped in the termi nal. It is not
necessary to tin the ends of the wire with solder or to add crimp ferrules to the wires; however, these techniques
are also compatible with the terminals and may ultimately make for a neater job.

Figure 2: Cable Connections

3.7 DC Power (DC PWR +, DC PWR –)

CF 147 3 version 1.1

The DC supply need not be regulated, provided that it is free of excessive electrical noise and sudden transients.
The instrument can be operated from a high quality AC wall transformer as long as there is sufficient capacity to
drive both it and the load cells.

3.8 Load Cell Connection

3.8.1 Load Cell Signals and Scale Build

Very low output scale bases may be used but may induce some instability in the weight readings when used with
higher resolutions. Generally speaking, the higher the output, or the lower the number of divisions, the greater the
display stability and accuracy.

The instrument can display the milliVolt-per-Volt reading that can be used to check scale base signal output levels.
For more information, refer to SCALE (Scale Base Test Display) section 7.4.8.
The instrument may be connected for either 4-wire or 6–wire operation. To correspond with the actual cabling
installation the instrument must be configured in setup to the correct setting. For more information, refer to CABLE
(4-Wire or 6-Wire) section 7.4.1.

3.8.2 4-Wire Connection

The minimum connectivity requirements are the connection of four wires (i.e. Excitation + and – along with Signal +
and –). Internally the instrument has a precision analog switch that can be used to connect the Sense + and – lines
directly to the Excitation + and – lines.

Any addition to the load cell manufacturer's cable length using 4-wire connection is only recommended for short
cable runs. Where long additions to cable lengths are neede d, a 6-wire extension is required.

The BUILD: CABLE option must be set to 4 to allow for 4-wire connection. Refer to CABLE (4-Wire or 6- Wire)
section 7.4.1.

Figure 3: 4-Wire Connections

3.8.3 6-Wire Connection

The excitation and signal lines are connected the same as for a 4-wire installation. The extra two wires (Sense +
and –) should be connected to the Excitation + and – lines as close as possible to the load cell itself. Typically
these connections are made in a load cell termination box.

The BUILD: CABLE option must be set to 6 (the default) to allow for 6-wire connection. Refer to CABLE (4- Wire or
6-Wire) section 7.4.1.

CF 147 4 version 1.1

Figure 4: 6-Wire Connections

3.9 Auxiliary Connections

This section provides diagrams to illustrate the terminal connections.

3.9.1 RS-232 Serial

• Direct Personal Computer Link (RXD, TXD, GND)

Figure 5: RS -232 - Instrument to PC using COM Port (DB9)

Figure 6: RS -232 – Instrument to PC using COM Port (DB25)

• Printer Connections (RXD/TXD, GND and DTR)

Figure 7: RS -232 – Instrument to Printer (DB25)

• Remote Display (TXD, GND)

The remote display documentation should be referred to for connection details. Connect TXD to RXD and GND to

GND on the remote display.

3.9.2 Remote Input

The indicator requires a voltage free contact between TXD and RXD to enable the remote input (ie.
SPEC:REM.FN). Note: The remote input will not function when in setup or when using the opto-LINK.

CF 147 5 version 1.1

Figure 8: Remote Input

3.9.3 Outputs

The output drivers for the instrument are isolated open emitter transistor drives that are capable of driving up to a
total of 300mA. This configuration allows for the direct connection of the instrument outputs to most PLC types.

The voltage applied to the COM terminal appears on the output lines (i.e. OUT1 and OUT2) when the outputs are
active (e.g. to connect to a PLC connect +24V to the common terminal). The outputs can then be connected directly
to PLC inputs so when activated the PLC will see the 22V signal (approx. - the exact switch loss will depend on
loading of the output).

To drive external loads (e.g. relays), connect the relay coil positive supply to the output common and the output line
directly to one side of the relay coil. Connect the other end of the relay coil to the negative supply. It is
recommended that fly-back diodes or transient suppressors be fitted across relay coils to limit switching noise.

Figure 9: Instrument Outputs to Drive Relay

Figure 10: Instrument Outputs to Drive PLC

3.10 GSE-LINK (Optional)

CF 147 6 version 1.1

A temporary infrared communications link can be established between the instrument and a PC using an optional
GSE-LINK cable. The optional GSE-LINK cable can be used to transfer setup and calibration information from a PC
(e.g. to be stored for later use and/or transferred to other ins truments). It can also be used to download software
upgrades to the instrument from a PC.

The PC end of the GSE -LINK cable is a standard female DB9 connector. The instrument end of the cable consists
of an infrared transceiver, which attaches to the left side of the instrument display. To facilitate a quick and simple
connection, the infrared transceiver is secured in place by a permanent magnet located within the head of the GSE­LINK.

Refer to GSE-LINK Activation section 5.7.1 for more information.

WARNING

The GSE-LINK head contains a strong magnet and care should be taken with its proximity to electronic
media (e.g. credit cards, floppy disks, etc.) and/or other electronic instrumentation.

Figure 11: GSE-LINK Attachment

3.11 Connecting Shields

To obtain full EMC or for RFI immunity, cable shields MUST be connected to the earth lug on the rear of the
instrument.

Figure 12 illustrates an example of possible connections. Also shown are the connecting cables restrained using
cable ties fastened around the cable strain relief anchors.

Figure 12: Cable Shield Connection

3.11.1 Cable Shield Connection and Earthing

• Care should be taken when connecting shields to maximize EMC or RFI immunity and minimize earth loops
and cross-talk (interference) between instruments.

• For full EMC or for RFI immunity, termination of the cable shields at the earth lug is very important. The earth
lug of the instrument must be separately connected to ground potential via a reliable link.

• The instrument should only be connected to earth via a single reliable link to avoid earth loops.

• Where each instrument is separately earthed, interconnecting cable shields should be connected at one end

CF 147 7 version 1.1

only.

• Caution: Some load cells connect the cable shield directly to the load cell (and therefore the scale base).
Connection of the load cell cable shield in this situation may be site specific.

3.12 Regulatory Sealing Requirements

To comply with regulatory sealing requirements for each instrument, (i.e. to ensure instruments are not accidentally
or deliberately tampered with), it is important that proper sealing procedures be adhered to. Refer to Sealing
section 12.2 for more information.

4.0 DATA ENTRY

Throughout the setup and normal weighing mode, different data entry methods are used. Eac h method is described
below.

When using the keypad for normal operation, press the key on keypad to initiate the feature.

4.1 Editing Annunciators

When in Setup the instrument displays editing annunciators. Figure 13 identifies each of the editing annunciators.
When in Setup, press the corresponding keypad key below the annunciator.

Figure 13: Editing Annunciators

Annunciator Key Name Description

GRP ZERO • Steps through the list of Groups.
ITM TARE • Steps through the list of Items.

• Press this ke y to accept changes and return to the menus.

• (Also refer to the OK description below.)
SEL GROSS/NET • Moves the editing cursor in some editing modes.
EDT PRINT • Steps through the available options when editing a particular item.
OK OK

(FUNCTION)

• Press this key to accept changes and return to the menus.

• (Also refer to the ITM description above.)

4.2 Numeric Entry

A numeric entry box allows the input of a number. When entering a number, the display will show digits with the
currently selected digit flashing. The <SEL> key is pressed to select a digit to change. When the digit is selected
the <EDT> key is pressed to change the digit from 0 through 9. The leftmost digit can also be changed to a dash (-)
to enter a negative number. The <OK> key is pressed to accept the number that has been entered and return to the
menu item.

Upper and lower limits are placed on some entries and an entry outside this range will cause the instrument to
display dashes (i.e. - - - - - -).

Example: When in Setup follow the steps below to set Build, Max Capacity.

• Press <GRP> repeatedly to display the BUILD group.

• Press <ITM> repeatedly to display the CAP item.

• Press <SEL> to select CAP and display the current setting (e.g. 0000.00lb).

CF 147 8 version 1.1