The Compax3 offers several types of communications, but comes standard with RS232 and RS485 (2 and 4 wire configurations) capabilities. All CTC products also come with the same capabilities. The below wiring diagrams document how to make these connections.
RS232
CTC to Compax 3 RS232 Wiring Diagram
Note: The Compax 3 does not have adjustable baud rates while using RS232. Also the standard 8 data bits, 1 stop bit and No Parity are used. If hardware flow control is required for the application then extra connections are required.
RS485 4-Wire
CTC to Compax3 RS485 4-Wire Wiring Diagram
The standard Parker serial cable part number SSK1/02 (green in color) supports this connection. The CTC documentation notes this as RS422 where the Compax3 notes this as RS485. These are the same with single point connection. The CTC drivers do not support RS485 multidrop. Thus if the CTC panel has 2 serial ports, then it could be used with 2 Compax3's.