To connect a Windows PC via RS485 to a Compax3 servo drive, B&B Electronics (www.bb-elec.com) makes a 485BAT3 RS232 to 422/485 converter.
From a 9pin COM port (or USB to RS232 adapter), connect straight through 9pin cable to the 485BAT3.
From the 485BAT3 for 2wire communication:
TD (B+) tied to RD(B+) goes to pin 7 on C3,
TD (A-) tied to RD(A-) goes to pin 3 on c3,
GND goes to pin 5 on C3
Switches: echo OFF, 485
C3: x10/pin 1 jumpered to x10/pin 9
From the 485BAT3 for 4wire communication:
TD (B+) to x10/pin 2 on C3 (RxD)
RD (A-) goes to x10/pin 3 on C3 (TxD/)
GND goes to x10/pin 5 on C3
RD (B+) goes to x10/pin 7 on C3 (TxD)
TD (A-) goes to x10/pin 8 on C3 (RxD/)
Switches: echo OFF, 422
C3: x10/pin 1 jumpered to x10/pin 9
RS232 C3 ServoManager connects at 115200 baud. RS485 is supported at 9600 through C3ServoManager. It can be used at different baud rates for third party devices and is set in Communications. Note changing the baud rate in C3 ServoManager software requires cycling power on the Compax3 and re-starting C3 ServoManager.
For RS485 communication, Device Address default is 1 and needs to be set in the C3 ServoManager software in Options > RS232/RS485 Settings PC <-> C3
To change back to RS232 in C3 ServoManager software, in this same window, select Reset to Default Values to change the baud back to 115200.