IMR02F04-E1
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1. OUTLINE
RKC communication and Modbus
The communication function makes it possible to monitor and set the data of the Pressure Indicator PG500 from
a computer.
The PG500 interfaces with the host computer via Modbus or RKC communication (ANSI
X3.28-1976 subcategories 2.5 and A4) protocols. The communication interface used for both protocols is
RS-485 or RS-422A. The host communication function (RS-485 or RS-422A) is available only if the
communication function is specified at the time of ordering.
In case of Modbus protocol, frequently used communication data can be grouped into a specified memory
address area for faster communication. This is called “Data mapping function.”
For reference purposes, the Modbus protocol identifies the host computer as master, the PG500 as slave.
One host computer (master) can communicate with up to 31 indicators.
Host computer (master)
RKC communication or Modbus (RS-485/RS-422A)
PG500 (
slave
) maximum connections: Up to 31 indicators
