Rinstrum 1203 User manual

1203
Weight Transmitte
r
Reference Manual
For use with Software Versions 1.0 and above
1203-600-172

RINSTRUM - 1203 Weight Transmitter Reference Manual Rev 1.7
Page 2
Copyright
All Rights Reserved. No part of this document may be copied, reproduced, republished,
uploaded, posted, transmitted, distributed, stored in or introduced into a retrieval
system in any form, or by any means (electronic, mechanical,
photocopying, recording or otherwise) whatsoever
without prior written permission of Rinstrum Pty Ltd.
Disclaimer
Rinstrum Pty Ltd reserves the right to make changes to the products
contained in this manual in order to improve design, performance or reliability.
The information in this manual is believed to be accurate in all respects at the time of
publication, but is subject to change without notice. Rinstrum Pty Ltd assumes no
responsibility for any errors or omissions and disclaims responsibility
for any consequences resulting from the use of the
information provided herein.
“Everything should be made as simple as possible, but not simpler.”
- Albert Einstein -

RINSTRUM - 1203 Weight Transmitter Reference Manual Rev 1.7
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Table of Contents
1. INTRODUCTION....................................................................................................... 5
1.1. Document Conventions .................................................................................. 5
2. SPECIFICATIONS .................................................................................................... 6
3. INSTALLATION ........................................................................................................ 7
3.1. Introduction..................................................................................................... 7
3.2. Power Supply.................................................................................................. 7
3.3. Load Cell Signals and Scale Build.................................................................. 7
3.4. Cable Shield Connection and Earthing........................................................... 7
3.5. Load Cell Connection ..................................................................................... 8
3.5.1. 6-Wire Connection.....................................................................................8
3.5.2. 4-Wire Connections...................................................................................9
3.6. Intrinsic Safety .............................................................................................. 10
3.7. Serial Communication Ports ......................................................................... 10
3.7.1. Serial 1: RS-232 Port...............................................................................11
3.7.2. Serial 2: RS-485 Port...............................................................................11
3.7.3. Multi-Drop Networking .............................................................................12
3.7.4. RS-232 Connection .................................................................................12
3.7.5. RS-485 Connection .................................................................................13
3.8. Input / Output: Setpoints............................................................................... 14
3.9. Input / Output: Inputs .................................................................................... 15
3.10. Analog Output............................................................................................... 16
3.11. Light Emitting Diode (LED) ........................................................................... 16
3.12. 1203 Viewer Software................................................................................... 16
4. CONTROLS ............................................................................................................ 17
5. DIGITAL SETUP ..................................................................................................... 18
5.1. Introduction................................................................................................... 18
5.2. Basic Weighing Terminology ........................................................................ 18
5.3. Direct mV/V Operation.................................................................................. 19
5.4. Filtering Techniques ..................................................................................... 19
5.4.1. FIR Filter .................................................................................................19
5.4.2. Digital Averaging .....................................................................................19
6. CALIBRATION........................................................................................................ 20
6.1. Introduction................................................................................................... 20
6.2. Digital Calibration with Test Weights ............................................................ 20
6.2.1. Digital Zero Calibration Routine...............................................................20
6.2.2. Digital Span Calibration Routine..............................................................20
6.3. Digital Direct mV/V Calibration...................................................................... 21
6.3.1. Digital Zero Calibration Routine...............................................................21
6.3.2. Digital Span Calibration Routine..............................................................21
6.4. Analog Output Calibration............................................................................. 21
6.4.1. Analog Calibration Routine ......................................................................21
7. SERIAL OUTPUTS ................................................................................................. 22
7.1. Introduction................................................................................................... 22
7.2. Automatic Weight Output.............................................................................. 22
7.3. Networking the 1203..................................................................................... 22
7.3.1. RS-485 Termination Resistors.................................................................22
8. EXTENDED FUNCTIONS....................................................................................... 23
8.1. Setpoints....................................................................................................... 23
8.1.1. Introduction .............................................................................................23
8.1.2. Status Indication......................................................................................23
8.1.3. Connection ..............................................................................................23
8.1.4. Operation ................................................................................................23
8.1.5. Example 1: Control Level of Product in 2000kg Tank ..............................24
8.1.6. Example 2: Control Weighing of Product Out of Silo into 100kg Drums ..24

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8.2. Remote Input ................................................................................................ 24
9. OPTIONS ................................................................................................................ 25
9.1. Display/Keys ................................................................................................. 25
9.1.1. Installation ...............................................................................................25
9.1.2. Setup and Calibration ..............................................................................25
10. COMMANDS........................................................................................................... 26
10.1. Overview....................................................................................................... 26
10.1.1. Commands and Queries..........................................................................26
10.1.2. Responses ..............................................................................................26
10.1.3. Parameters..............................................................................................26
10.1.4. Termination .............................................................................................26
10.2. Command Details ......................................................................................... 27
10.2.1. ACL: Set Automatic Temperature Calibration On/Off ..............................27
10.2.2. ADR: Set Address ...................................................................................28
10.2.3. ANL: Set Analog Output ..........................................................................29
10.2.4. ANM: Set Analog Output Maximum and Minimum...................................30
10.2.5. ASF: Set Filtering ....................................................................................31
10.2.6. BDR: Set Baud Rate................................................................................32
10.2.7. COF: Set Output Format .........................................................................33
10.2.8. ESR: Query Error Status .........................................................................36
10.2.9. FCN: Execute A Function ........................................................................37
10.2.10. HYS: Set Hysteresis ................................................................................38
10.2.11. IAD: Set Scale Build ................................................................................39
10.2.12. IDN: Set Identification..............................................................................40
10.2.13. LDW: Calibrate Zero Dead Weight ..........................................................41
10.2.14. LIV: Set Limit Value.................................................................................42
10.2.15. LWT: Calibrate Span ...............................................................................43
10.2.16. MSV?: Query Measured Weight Value ....................................................44
10.2.17. RBT: Remote Button Settings .................................................................45
10.2.18. RES: Reset..............................................................................................47
10.2.19. SER: Set Serial Communications Settings ..............................................48
10.2.20. STP: Stop Continuous Transfer...............................................................49
10.2.21. Sxx: Select Unit .......................................................................................50
10.2.22. TAR: Tare................................................................................................51
10.2.23. TDD: Load/Save Setup............................................................................52
11. APPENDIX .............................................................................................................. 53
11.1. Glossary of Terms ........................................................................................ 53
11.2. List of Figures and Tables ............................................................................ 53
12. INDEX ..................................................................................................................... 54

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1. Introduction
The 1203 is a precision digital weight transmitter using the latest Sigma-Delta A/D
converter to ensure extremely fast and accurate weight readings.
The setup and calibration are digital, with a non-volatile security store. All setup
parameters and important operating settings (Zero / Tare, etc.), are retained when power
is removed.
The 1203 can output both 4-20mA and 0-10V analog. These outputs can be calibrated by
the user to output any range.
The instrument has two trip points with output drive and status display via LEDs.
The 1203 provides two serial outputs. These allow communication with external
computers, PLCs and remote displays. Serial 1 provides RS-232 while Serial 2 provides
4-wire RS-485.
Figure 1: 1203 Weight Transmitter
1.1. Document Conventions
The following conventions (typographical) are used throughout this Reference
Manual.
Bold Text Bold text denotes words and phrases to note.
^ This symbol denotes one space (used in 1203 Commands)
… Ellipses indicate an incomplete listing. For space considerations in
this Reference Manual complete listings of returned Command
responses may not be shown.

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2. Specifications
General
Operating
Environment
Temperature: –10 to +50°C ambient, Humidity: <90% non-condensing
Power Supply 12VDC at 500mA max to 24VDC at 250mA max
Instrument
Variations
1203 Weight
Transmitter
Enclosure Class: IP55+/NEMA Enclosure Material: Aluminium
Dimensions: 170 x 120 x 55 or 170 x 145 x 55 including cable gland
P/No: 1203
1203 Weight
Transmitter with
Display
Enclosure Class: IP55+/NEMA Enclosure Material: Aluminium
Dimensions: 170 x 120 x 55 or 170 x 145 x 55 including cable gland
Window: Acrylic/polycarbonate (Not for use in full sun). P/No: 1203/D
1203 Weight
Transmitter - PCB
Only
P/No: 1203/B
Analog Input
Stability/Drift Zero: <0.1µV/°C, Span: <10ppm/°C,
Linearity: <20ppm, Noise: <0.05µVp-p
Span Adjustment 0.1mV/V to 3mV/V capacity
Calibration Digital, Non-Volatile
Digital Filter Averaging 1, 2, 4, 8, 16, 32, 64, 128 or 256 readings (10ms to 2.56s)
A/D Converter Type: 24bit Sigma Delta
Resolution: 8,388,608 internal counts
Load Cells Excitation: 8VDC Connection: 6-wire + shield
Available Excitation Current: 150mA (6 x 350Ωload cells)
Sampling Rate 100Hz
Analog Output
Type Configurable (4-20mA, 0-24mA, 0-20mA, –10-10V, 0-10V, 2-10V, 0-5V,
1-5V, etc)
Overall Error <0.1%
Isolation >500V
Impedance Maximum current-loop impedance: 1000Ω
Minimum impedance between voltage outputs: 2000Ω
Update Rate 100Hz (50Hz when scaled to user calibration)
Communications
Serial Output RS-485 full duplex and RS-232 full duplex
Capability Automatic transmit and network
Network Protocol HBM AED/WE2110
Input / Output
Isolated Input Number of isolated inputs: 1
Input Voltage Range Active input voltage range: 5-28VDC
Input Current
Requirements
1.5mA at 5VDC to 13mA at 28VDC
Transistor Output Number of isolated transistor outputs: 2
Load Output Maximum load on output: 300mA
Voltage Output Maximum operating voltage on output: 30VDC
Output Protection Reverse and short-circuit protected
Output Update Rate 100Hz (50Hz when scaled to user calibration)
Options
1203 Display Service
Tool
6 LED digits 14mm high with 4 Annunciators, 4 Units and 4 Buttons
P/No: 1203/S
1203 Viewer Package Viewer software, RS-232 cable and Reference Manual. P/No: 1203/V
Other
Calibration Transferable calibration
Safety Standards C-tick approved. CE approved. UL approval pending.

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3. Installation
3.1. Introduction
The 1203 must not be subject to shock, excessive vibration, or extremes of
temperature, either before or after installation.
The inputs of the 1203 are protected against electrical
interference, but excessive levels of electro-magnetic
radiation and RFI may affect the accuracy and stability of the
instrument. The 1203 should be installed away from any
sources of electrical noise. The load cell cable is particularly
sensitive to electrical noise and should be located well away
from any power or switching circuits.
Figure 2: Power Supply
3.2. Power Supply
The power supply is connected using the power connector (J12). The DC supply
need not be regulated, provided that it is free of excessive electrical noise and
sudden transients. The 1203 can be operated from a high quality plug-pack as long
as there is sufficient capacity to drive both it and the load cells.
The unit is constructed to use 12-24 VDC only. Voltages outside this range may
cause improper operation or damage.
3.3. Load Cell Signals and Scale Build
Very low output scale bases can be used with the 1203 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 1203 has a millivolt-per-volt reading available which can be used to check scale
base signal output levels.
IMPORTANT NOTICE
3.4. Cable Shield Connection and Earthing
• Care should be taken when connecting shields to maximise EMC immunity and
minimise earth loops and cross-talk (interference) between instruments.
• For EMC immunity, termination of the load cell shield at the 1203 end is important
(ie. with connection to the 1203 case via the shield connection).
• 1203 enclosure is directly connected to the shield connections on the terminal
blocks.
• 1203 should 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 only.
• Caution: Some load cells connect the cable shield directly to the load cell (and
therefore the scale base). Connection of the shield in this situation may be site
specific.
• Unit complies with relevant EMC standards provided case ground connection is
correctly made. Resistance measured between 1203 case and nearest earth point
should be less than 2 ohms.

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3.5. Load Cell Connection
The following provides information on 6-wire and 4-wire connections.
3.5.1. 6-Wire Connection
When wiring load cells, use only high quality shielded multi-core cable. The cable
should be run as far away from any other cabling as possible (minimum separation
distance 150mm). Do not bundle load cell cables with power or control-switching
cables as interference can trigger display instability, and cause unreliable
operation.
The connection is made using the load cell connector (J4). The load cell is wired for
a 6-wire system as follows:
Terminal Function
1 Positive Signal
2 Negative Signal
3 Positive Sense
4 Negative Sense
5 Positive Excitation
6 Negative Excitation
7,8 Shield
Table 1: 6-Wire Connections
*For more information on shielding refer to page 7.
Figure 3: Load Cell: 6-Wire Connections
Note: Sense lines MUST be connected.

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3.5.2. 4-Wire Connections
The 1203 is not fitted with auto-sensing of the load cell excitation. This is intentional
on this unit to optimise the performance across all applications, including those
involving intrinsic safety barriers.
When a 4-wire load cell system is connected, terminals 3 & 5 and 4 & 6 must be
joined by wire bridge. This is to ensure that the excitation voltages are fed into the
sense inputs (terminals 3 & 4). Failure to do this will result in the 1203 displaying
the error code E0040 and/or E0080. Refer to Error Codes page 36 for more
information. The unit will not operate correctly if the sense wire bridges are not
connected.
*For more information on shielding refer to page 7.
Figure 4: Load Cell: 4-Wire Connections

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3.6. Intrinsic Safety
The 1203 has been designed to operate in installations with intrinsic safety barriers
down to Class 1, Zone 1. The following diagram shows a suggested method of
installing the 1203 with safety barriers for up to four load cells.
Figure 5: Sample Installation Method - 1203 with Safety Barriers
Note: As the regulations concerning intrinsic safety can vary from country to
country, consult local regulations before attempting such an installation. Special
attention should be paid to the grounding of the 1203 and the barrier system.
3.7. Serial Communication Ports
There are two serial communication ports on the 1203.
• Serial 1 is a full duplex RS-232 connection.
• Serial 2 is a full duplex, 4-wire RS-485 connection.
Both ports can be used as network or automatic output ports. The two ports can be
connected using the communications connector (J6) or using the DB9 connector
(J1). The DB9 is primarily intended for use as a short-term configuration and
diagnostic connection.
The serial ports on the 1203 are not completely independent. Commands cannot
be sent to the 1203 on both ports simultaneously. Also, the 1203 cannot identify
which port received the command so all replies are sent to the configured network
port(s).
The serial ports are configured using the SER and BDR commands. The Comms
Reset switch (SW1) sets the serial ports to a known state. For versions 1.6 and
below, this state will become permanent when a save is performed. For versions
1.7 and above, this state (viewer mode) is temporary and another press will return
the 1203 to normal operation.
Short Press (< 2 seconds)
Will Set:
• Comms to 9600n81
• RS-232 to Network
• RS-485 to OFF
Long Press (>= 2 seconds)
Will Set:
• Comms to 9600n81
• RS-232 to OFF
• RS-485 to Network
Figure 6: Comms Reset Switch (SW1)

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3.7.1. Serial 1: RS-232 Port
All connections for this port are on the communications connector (J6) and on the
DB9 connector (J1).
Note: Terminals 5 to 7 of the communications connector (J6) are connected
directly to pins 2, 3 and 5 of the DB9 connector (J1). This provides for quick and
convenient connection of test or debug systems.
The connections for the outputs are shown below:
J1 Pin No J6 Terminal No Function Description Connect to
2 7 RXD RS-232
Receive Line
External Device
Transmitter
(Usually Pin 3)
3 5 TXD RS-232
Transmit Line
External Device
Receiver
(Usually Pin 2)
5 6 GND RS-232
Digital Ground
External Device Digital
Ground
(Usually Pin 5)
Backshell 8 Shield Cable Shield
Table 2: Serial 1: RS-232 Port - Connection Outputs
3.7.2. Serial 2: RS-485 Port
All connections for this port are on the communications connector (J6) and on the
DB9 connector (J1).
Note 1: The 1203 supports 4-wire full duplex RS-485 only (ie. 2-wire half-duplex
communications are not supported).
Note 2: Terminals 1 to 4 of the communications connector (J6) are connected
directly to pins 6 to 9 of the DB9 connector (J1) - (J6.1-J1.9, J6.2-J1.8, J6.3-J1.7,
J6.4-J1.6). This provides for quick and convenient connection of test or debug
systems.
J1 Pin No J6 Terminal No Function Description Connect To
7 3 RA(-) RS-485 Receive A (-) External Network
6 4 RB(+) RS-485 Receive B (+) External Network
9 1 TA(-) RS-485 Transmit A (-) External Network
8 2 TB(+) RS-485 Transmit B (+) External Network
Backshell 8 Shield Cable Shield
Table 3: Serial 2: RS-485 Port - Connection Outputs

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3.7.3. Multi-Drop Networking
The following table shows how to connect a number of instruments in an RS-485
4-wire multi-drop network:
Cable 1 Cable 2
Network
Master
1203 - Unit 1 1203 - Unit 1 1203 - Unit 2
Function Function Terminal
(J6)
Function Terminal
(J6)
Function Terminal
(J6)
RA(-) TA(-) 1 TA(-) 1 TA(-) 1
RB(+) TB(+) 2 TB(+) 2 TB(+) 2
TA(-) RA(-) 3 RA(-) 3 RA(-) 3
TB(+) RB(+) 4 RB(+) 4 RB(+) 4
Table 4: Multi-Drop Networking Connections
Note: For more than two units, duplicate Cable 2 between each new unit and the
network.
The end devices in a multi-drop RS-485 network may need to be provided with
termination resistors to balance the network loadings. These resistors are built into
the 1203 and they can be enabled or disabled using the digital setup. Refer to
BDR: Set Baud Rate page 32 for more information.
3.7.4. RS-232 Connection
*For more information on shielding refer to page 7.
Figure 7: RS-232 Connection (J1) & (J6)

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3.7.5. RS-485 Connection
*For more information on shielding refer to page 7.
Figure 8: RS-485 Connection (J1) & (J6)

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3.8. Input / Output: Setpoints
The 1203 has two setpoint outputs. The setpoints are configured using the LIV and
HYS commands. For Specifications refer to page 6.
The connections for these outputs are available on J10 as follows:
Terminal Function Connect To -
Open Collector
(Current Sink)
Connect To -
Open Emitter
(Current Source)
5 Output 1+ External Load 1- Power Supply +
6 Output 1- Power Supply - External Load 1+
7 Output 2+ External Load 2- Power Supply +
8 Output 2- Power Supply - External Load 2+
*For more information on shielding refer to page 7.
Figure 9: Input / Output - Setpoints (J10)

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3.9. Input / Output: Inputs
The 1203 has one digital input. This input is configured using the RBT command.
For Specifications refer to page 6.
The connections are available on J10 as follows:
Terminal Function Connect To -
Option 1
Connect To -
Option 2
1 Input + External Switch - Power Supply +
2 Input - Power Supply - External Switch +
*For more information on shielding refer to page 7.
Figure 10: Input / Output: Inputs (J10)

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3.10. Analog Output
The analog output is connected using the analog out connector (J8). The 1203 has
one analog output. This output can be either voltage or current. It is configurable
within the limits of –10 to 10V or 0 to 24mA. The default is 0-10V or 4-20mA. The
output is configured using the ANL and ANM commands.
The connections are available on J8 as follows:
Terminal Function Connect To
1 Voltage + External Load +
2 Voltage - External Load -
5 Current + External Load +
6 Current - External Load -
*For more information on shielding refer to page 7.
Figure 11: Analog Out Connections
3.11. Light Emitting Diode (LED)
The flashing green LED indicates the 1203 is On.
The green LED On but not flashing indicates that the 1203 is still starting or that
the 1203 is in viewer mode.
The flashing red LED indicates the 1203 is experiencing an error. The ESR
command is used to query the error status of the instrument. Refer to ESR: Query
Error Status page 36 for more information.
3.12. 1203 Viewer Software
The 1203 Viewer Software can be used in the setup of the instrument. The Viewer
Software is available by contacting Rinstrum or from the web site at
www.rinstrum.com.

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4. Controls
The 1203 controls consist of a single button (SW1). The function of this button depends
on the 1203 software version:
• For versions 1.6 and below, this button resets the communications to the following
settings:
Control Setting
Baud 9600
Parity None
Data Bits 8
Stop Bits 1
• A short press of the SW1 button (50ms < t < 2s) sets the RS-232 port in network
mode and disables the RS-485 port.
• A long press of the SW1 button (t >= 2s) sets the RS-485 port in network mode
and disables the RS-232 port.
Note: These new settings will become permanent if a save is performed.
• For versions 1.7 and above, this button sets the 1203 in Viewer Mode. Viewer mode is
not permanent and another press of the button will exit this mode. While in viewer
mode, the 1203 communications are set to the following settings regardless of what is
configured:
Control Setting
Baud 9600
Parity None
Data Bits 8
Stop Bits 1
• A short press of the SW1 button (50ms < t < 2s) sets the RS-232 port in network
mode and disables the RS-485 port.
• A long press of the SW1 button (t >= 2s) sets the RS-485 port in network mode
and disables the RS-232 port.

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5. Digital Setup
5.1. Introduction
Digital setup of the 1203 can be carried out using the serial communications links or
by using the 1203/S Service Tool (Display/Keys). For more information on the
optional display refer to the 1203 Display Manual.
There is no password to secure setup and calibration via the serial communications
link.
5.2. Basic Weighing Terminology
The following terms are used throughout the setup procedure. Knowledge of these
basic weighing terms is beneficial in setting up and calibrating the 1203.
Note: Detailed descriptions of these and other terms used in this Reference
Manual are described in the Glossary of Terms page 53.
Term Definition
Units Units of measurement (kilograms, tonnes, pounds, etc.).
Capacity Maximum gross weight allowed on the scale.
Resolution or
Count-by
Smallest change in weight units that the display can show.
Graduations Maximum number of display steps between zero gross load and
full capacity gross load.
Division A single graduation.
Example
A 10,000kg 2.0mV/V load cell is used in an application with a 5000kg range,
displaying in 5kg divisions.
The values of each of the above terms are:
• Units = kg
• Capacity = 5000
• Count-by = 5
• Graduations = 1000
The Signal Voltages are:
• The capacity load cell signal is (5,000 / 10,000) x 2.0mV/V = 1.0mV/V.
• Since the 1203 uses 8V excitation, the absolute signal voltage is 8 x 1.0 =
8.0mV.
The Signal Resolution is therefore:
• 8.0 / 1000 = 0.008mV / division or 8µV / division.

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5.3. Direct mV/V Operation
If the output capacity of the load cell is known, the 1203 can be calibrated without
test weights. This is useful for applications where it is impractical to use test
weights (eg. silo weighing).
This mode of operation allows the following signal strengths to be entered directly:
• mV/V (at no load)
• mV/V (of the span)
This type of calibration is only as accurate as the load cell output figures. For many
applications this is more than adequate. Refer to Calibration page 20 for more
information.
5.4. Filtering Techniques
The 1203 has filtering options available which allow it to be optimised to produce
the most accurate readings possible in the shortest time. There is a trade-off
between noise filtering and the step-response time of the system. The filtering
options define the amount of time required to determine a final weight reading (not
the number of readings per second that are produced).
5.4.1. FIR Filter
The first level of filtering is the FIR filter. This is linked to the measurement rate.
The measurement rate is fixed at 100Hz. This filter is a very high performance
“tuned” filter that provides up to 180 dB of attenuation at multiples of the SYNC
frequency. It also provides broadband filtering of between approximately 40 and 80
dB.
5.4.2. Digital Averaging
The second level of filtering is the digital averaging. Digital averaging is
implemented as a fixed length sliding window average where the average of the last
“n” readings is calculated. As each new reading is taken the oldest reading is
discarded and a new average is calculated. The length of the window is set with the
ASF command using from 1 to 256 readings. Each reading in the average adds a
delay to the step-response equal to the measurement period.
Example
An average of 10 readings results in a total step-response of (10 + 3) * 10 = 130
milliseconds (where 3 samples is the fixed delay added by the FIR filter).

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6. Calibration
6.1. Introduction
The calibration of the 1203 is fully digital and can be carried out using the serial
communications links or by using the 1203/S Service Tool (Display/Keys). The
calibration results are stored in permanent memory for use each time the unit is
powered up.
The 1203 uses the following three digital calibrations simultaneously.
Calibration Changeable Details
Raw No This calibration is fixed.
mV/V No This calibration is fixed.
User Yes This calibration can be changed.
Performing a User Calibration is not a requirement
however, as the factory calibration is complete.
If a User Calibration is to be performed, the IAD,
ANL, ANM, LDW and LWT commands are used.
Refer to Commands page 26 for more information.
Note: It is important to perform the zero
calibration before the span calibration.
6.2. Digital Calibration with Test Weights
6.2.1. Digital Zero Calibration Routine
• Remove all weight from the scale structure.
• Send the LDW command to the instrument. To get very accurate data, the
instrument increases the averaging for this step and will require 3 to 4 seconds
to complete. While calibrating, the response to any command will be 1. For
example, LDW? will return 1while calibrating followed by x(where xis the
zero value in mV/V), when calibration is completed.
• When the calibration is complete send the TDD1 command to save the
calibration to EEPROM.
6.2.2. Digital Span Calibration Routine
• Add the calibration test mass to the scale. A small weight (eg. <5% load cell
capacity) may limit calibration accuracy. The closer the test weight is to full
user range, the better the accuracy.
• Use the IAD command to setup scale build information.
• Send the LWT command with the test weight in user value without decimal
points. For example, send LWT1000 for a calibration of 300kg (capacity) in
0.1kg graduations (3000 graduations total) and a test weight of 100kg. To get
very accurate data, the instrument increases the averaging for this step and
will require 3 to 4 seconds to complete. While calibrating, the response to any
command will be 1. For example, LDW? will return 1while calibrating followed
by x(where x is the zero value in mV/V), when calibration is completed.
• When the calibration is complete send the TDD1 command to save the
calibration to EEPROM.