MERIDIAN
UNIVERSAL GAS DETECTOR
CONFIGURATION & SETUP
5-55
USE AND DISCLOSURE OF DATA
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prohibited.
5.5. Using the TXCommands
Use the TXCommand to execute a MODBUS function and to set configuration parameters. The individual registers
are readable at their address. To write a command/parameter to the transmitter, use a write to the MODBUS
TXCommand. There are different write commands for the various data types. Some commands require only the
TXCommand register to be written, while other commands require addition parameters. They must be written to
before the command is written into the command register.
Structure of Configuration Registers for
TxWriteString 0xX204 Upper Nibble with Param1 ... Param10 (2 of 2)
details about the TXCommand structure and individuals TXCommands. TX=0, Sensor1=1, Sensor2=2, Sensor3=3.
WARNING:
EXECUTING WRITE REGISTER FUNCTIONS WILL ALTER EXTERNAL DEVICES
AND THUS THEIR BEHAVIOR. NEVER WRITE TO ANY PLC ADDRESS UNLESS YOU
UNDERSTAND THE DEVICE PERFORMANCE OR OPERATION CHANGES THAT WILL RESULT
AND HAVE DETERMINED THAT THE CHANGES WILL NOT CREATE AN UNSAFE SITUATION.
ALWAYS FOLLOW THESE GUIDELINES WHEN CHANGING MODBUS REGISTERS:
• ONLY QUALIFIED PERSONNEL SHOULD MAKE CHANGES TO MODBUS REGISTERS.
• ALWAYS TEST YOUR CHANGES IN A TEST LAB ENVIRONMENT.
• ALWAYS VERIFY YOUR MODBUS REGISTER CHANGES PRIOR TO IMPLEMENTATION IN A
FUNCTIONAL PLANT ENVIRONMENT.
• FOR REMOTE LOCATIONS, VERIFY ALL MODBUS CHANGES FUNCTION AS INTENDED
PRIOR TO IMPLEMENTATION IN A FUNCTIONAL PLANT ENVIRONMENT.
FAILURE FOLLOW THESE GUIDELINES COULD RESULT IN SERIOUS INJURY OR DEATH.
NOTE: Consult the technical documentation provided with the receiving equipment in conjunction
with the tables provided herein for configuration of MODBUS (WR and RD). The MODBUS register
mapping may vary.
