Making a PC Serial Port (DB9) to Copley RJ11 Cable

The Copley digital drives use a serial port for setup and commands. Even on the CANOpen models, it is necessary to first connect using the serial port to set the CAN bit rate, verify the address, and, if you don't have a Copley/NI/Kvaser CAN interface, to setup the amplifier. It's very easy to make the required cable yourself.

I have tested my cables on Copley Accelnet Panel and Stepnet drives, but they should work on any Copley with a RJ11 serial port, such as the Xenus Panel, Junus Panel, Accelus Panel, and Stepnet AC.

There are two approaches: either use a DB9/RJ11 modular adapter and a RJ11 cable, or solder a DB9 to a RJ11 cable. The modular adapter approach does not require any soldering; however, I think the RJ11 cable + DB9 looks better.

A note on RJ connectors: RJ11 and RJ12 connectors are mechanically the same, with space for 6 pins (6P). The RJ12 connector has 6 connections (so it's 6P6C), while the RJ11 has 4 connections (6P4C). Some people use RJ11 to refer to both RJ11 (6P4C) and RJ12 (6P6C).

Using a DB9/RJ11 Modular Adapter

I used a AIM-Cambridge/Emerson 40-9536F RJ12 to DB9F adapter kit. AIM does not offer a RJ11(6P4C)/DB9 adapter kit. The kit comes with a backshell with a RJ12 connector inserted with 6 flying leads (terminated in female crimp connectors) and a DB9F crimp connector.

I also tried a Pan Pacific ADM-9F6-GR DB9F/RJ11 (6P6C) Modular Adapter kit from Fry's Electronics. It is very similar to the AIM, including the wire colors. The Pan Pacific's longer thumbscrews do make it harder to remove the patch cable.

Connections using AIM 40-9536F or Pan Pacific ADM-9F6

DB9F PinSignalRJ12 PinWire ColorRJ12 Signal
2Rx Receive Data5 Black TxD Send Data
3Tx Send Data 2 Yellow RxD Receive Data
5Signal Ground 3 or 4Green or RedSignal Ground
1 Blue
6 White

Copley pins 3 and 4 are both Signal Ground, and are connected together internally, so you can connect either one to the DB9's Signal Ground.


  1. If the modular adapter isn't a AIM 40-9536F or Pan Pacific ADM-9F6, then you need to determine which wires are connected to which pins.
    1. With the contacts on the bottom, RJ12 pin 1 is the contact on the far right.
  2. Carefully insert the crimped pins into the appropriate hole in the DB9F connector until they snap into place and won't come out. A small screw driver or insertion tool can help.
    1. Be careful - so far in my experience, removing DB crimp pins is a huge pain. If you don't have the proper tools, it's just about impossible.
  3. Test the connection - connect a RJ11 (6P4C or 6P6C) patch cable between the Copley and the modular adapter, then plug the modular adapter into the computer, turn on the Copley, and test the connection using Copley's CME2 setup software.
  4. Once you've verifed it works, chop off the extra wires.
  5. Snap the DB9F connector into the backshell, pushing the the wires into the backshell.
  6. Test again
AIM Modular Adapter setup for Copley serial port
Assembled AIM Modular Adapter with RJ12 (6P6C) Patch Cable
Assembled Pan Pacific Adapter with RJ12 (6P6C) Patch Cable

Using a RJ11 or RJ12 Patch Cable and DB9F Connector

The basic procedure here is very simple: get a RJ11 or RJ12 cable, identify the wire colors, cut off one end, and solder a DB9 to the cut off end.

I used a RJ12 (6P6C) patch cable, but a RJ11 (6P4C) cable would work just as well.

Connections using RJ12 Patch Cable (bought at Fry's)

DB9F PinSignalRJ12 PinWire ColorRJ12 Signal
2Rx Receive Data5 Yellow TxD Send Data
3Tx Send Data 2 Black RxD Receive Data
5Signal Ground 3 & 4 Red & GreenSignal Ground
1 White
6 Blue

Note that the wire color coding is different from the AIM modular adapter. Since I used a solder cup DB9F connector, I connected both RJ11 Signal Grounds to the DB9 Signal ground.

Bill of Materials ==

  1. RJ12 or RJ11 Patch cable of the desired length (I'd recommend less than 25 feet)
  2. DB9 Female connector
  3. DB9 Backshell


  1. Identify which wire color is for which pin. Pin 1 on the plug is the farthest left connector, when the clip is facing away from you. If the plug is clear, normally you can visually identify the colors. If you can't, you will have to meter.
  2. Cut off one end, and then strip the wires.
  3. If you are using a backshell, you should see if any pieces need to go over the cable before you connect the DB9. My backshell needed the strain relief to be placed on the cable first.
  4. Solder the cable to the connector. You could also use a crimp DB9F connector, but in that case you need to ensure the crimp pins are properly sized for the cable wires, and you will have to decide if you want to connect one or both of the RJ11 Signal Grounds.
  5. Test the connection - connect the cable to the Copley and your computer, turn on the Copley, and test the connection using Copley's CME2 setup software.
  6. Once you've verifed it works, install the backshell.
  7. Test again.
RJ12 Patch Cable Wired to DB9F (I don't claim to be great at soldering, but it works)
Finished RJ12 to DB9F serial cable.

Last modified 4 years ago Last modified on Jun 19, 2013 11:54:57 PM