GE 90-30 PLC Series Installation And Hardware Manual page 210

8
Applications
These modules are used for communicating with programming terminals, CRTs, bar code readers,
scales, printers, ASCII devices, RTU master devices, etc.
PCM Module Location
A PCM can be installed in any slot in the CPU baseplate only, except slot 1 (labeled CPU/1), which
must contain the CPU module. A PCM will not work in Expansion or Remote racks or in an
Embedded CPU (CPU311, 313, or 323) rack.
Protocols Supported
Modbus RTU and GE CCM.
LED Indicator Lights
Restart Pushbutton
Used to place the module in either the RUN mode or the PROGRAM mode. Please see "PCM
Operation Modes" in GFK-0255, Chapter 1.
Memory Backup Battery
The Lithium battery for backup of RAM memory is installed in a battery mounting clip on the
inside of the PCM faceplate. This battery is disconnected for shipment from the factory and must
be connected prior to installation of the module. When the PCM is stored for extended periods of
time, the battery should be disconnected, unless you wish to retain the program in RAM memory.
Order replacement batteries using catalog number IC693ACC301 (package of two).
Cables
IC693CBL304/305 - These Wye cables split out the two PCM port connections from the single
connector on the front of the PCM modules. One of these cables is supplied with each PCM
module. The IC693CBL304 is for the PCM300. The IC693CBL305 is for the PCM301 and
PCM311. Please see Chapter 10 for details on these cables.
IC690CBL701/702/705 - These cables provides a direct RS-232 connection between the PCM and
various programmers' serial ports. These cables are not supplied with the PCM modules. Please
see Chapter 10 for details on these cables.
8-32 Series 90-30 PLC Installation and Hardware Manual – August 2002
OK -Normally ON. Indicates the basic condition of the module.
US1 and US2 - By default, LED US1 flashes to indicate activity on Port 1, and LED US2
flashes to indicate activity on Port 2. Both LEDs stay OFF when there is no port activity.
However, the function of these two LEDs can be custom configured by the user. Please see
GFK-0255 for custom configuration details.
GFK-0356Q