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RS485 PROTOCOL
The commands sent to the controller must have the following format:
• 2-digit process ID number
• 3-character command name
• Parameters (variable length, may be null)
• End of command (always the CR character,
Hex 0D)
A maximum time interval of 20 ms is allowed between two consecutive characters of
a command.
It is possible to send commands to change the controller settings or to simply ask
information on the controller status.
Following is the complete list of commands available:
The Fail-Safe resistors are connected only to one unit in the line, and their value depends
on the application and characteristic impedance of the connection cable.
The RS485 port is optoisolated from measuring circuit and power line. The analog output
and RS485 port have the same ground.
