KEP MMI-7 Series Installation Instruction page 7

4.2 CONNECTION TO A CONTROLLER
Different cables are required for various devices. See Controller Reference Section
Cable
for cable details. The KEP part numbers have the SMIC prefix. Refer to a KEP
Requirements
catalog or data sheet for a complete listing of MMI compatible devices.
These cables can be obtained from the same distributor where you purchased the
MMI.
Communications problems cause the display to show "PLC no response..." until
Error
communications can be established. During this time, the controller cannot be
Messages
affected by the MMI. The COM light on the front of the MMI turns on with each
communication and should appear as if always on or slightly flickering when
communications are good.
Restrict cable length to avoid communications problems due to weak signals.
Shielded cable must be used for long lengths or cables run in an electrically noisy
environment.
Use twisted pair cables for all Ethernet connections.
Do not run cables next to AC power lines or near sources of electrical noise.
Be sure that the cable ends have been inserted all of the way into mating connectors
and are secure.
Pin assignment of the 9 Pin, Female, D-SUB, PLC [RS-232] Port. This port is
used for connecting the MMI to a controller or Master MMI unit. The Auxiliary
(AUX) RS232 port is also accessed through this connector. Both PLC and AUX
Pin Designations
ports share the common ground.
Note: This port is not used for programming the MMI or for printing functions.
Pin
Recommended distances:
RS232: less than 50' (15m)
RS485/422: less than 500' (150m)
Ethernet: less than 328' (100m)
Do not plug the MT5_PC's PLC cable end into this port.
Symbol PLC[RS232]
#
1 AUX TxD
2 PLC TxD Transmitted Data
3 PLC RxD Received Data
4 Not used
5 GND Signal Ground
6 AUX RxD
7 PLC CTS Clear to send input
8 PLC RTS Ready to send output
9 Not used
AUX[RS232]
Transmitted Data
Received Data
Signal Ground
7