Version 1 (modified by TonyB, 6 years ago) (diff)


CO-HDR-RJ45 CANOpen Adapter


Purpose: converts a CANOpen DS303-1 5 Pin 5.08mm terminal block connector to two DS303-1 RJ45 connectors, provides optional connection to CAN_V+.

Files are here for subversion (Eagle PCB files) and here for WordPress (Eagle PCB files)

I have standardized on RJ45 connectors for my CANOpen equipment. This adapter makes it easy to connect CANOpen equipment with compatible terminal block headers (such as the Wago 750-337) to RJ45 CANOpen networks. I provide a connection for CAN_V+ in case it's needed.

Design Notes

The various signal lines are connected as follows:

  • CAN_H is connected to J1A (first RJ45 jack), J1B (second RJ45) and P1 (5-pin inverted terminal block plug)
  • CAN_L is connected to J1A, J1B, and P1
  • CAN_GND is connected to J1A, J1B, P1, and TB1 (power input terminal block)
  • CAN_SHIELD is connected to J1A, J1B, and P1
  • J1 reserved pins are connected: J1A pin 4 is connected to J1B pin 4 and J1A pin 5 is connected to J1B pin 5
  • TB1 CAN_V+ is always connected to P1 CAN_V+
  • TB1 CAN_V+ can be connected to J1A CAN_V+ and J1B CAN_V+ by using jumpers.

Normal Use

  • Verify your device has a compatible header and pin-out. The pin out is below.
    • Apparently there's a slight difference between Wago (used by the Wago 750-337) and Phoenix terminal blocks. I had to break off one of P1's tabs to get it to fit in the Wago 750-337. (You can see that in the above picture).
  • Connect J1A and J1B to the rest of the CANOpen network using RJ45 cables
  • If the CANOpen device needs power on CAN_V+ (Wago 750-337's do not), you have many options:
    • Connect CAN_V+ power from TB1 to only this device: both jumpers are removed from JP1
    • Connect CAN_V+ power from TB1 to this device and all devices connected to the left RJ45 jack: only left JP1 jumper is installed
    • Connect CAN_V+ power from TB1 to this device and all devices connected to the right RJ45 jack: only right JP1 jumper is installed
    • Connect CAN_V+ power from TB1 to entire RJ45 network: both JP1 jumpers are installed
    • Break the link between CAN_V+ on the right RJ45 and the left RJ45: both jumpers are removed from JP1
  • So JP1 provides a lot of flexibility in providing multiple CAN_V+ voltages to your network -- but, as always, be careful, since you don't want to provide, say, +24VDC CAN_V+ to a device designed for +12VDC.

Bill of Material

PartVendorPart NumberQuantityDescription
PCBYour fab house 1
P1Phoenix ContactIC 2,5/5-G-5,08 P/N 178643315-pin 5.08mm inverted terminal block header
J1TE/AMP5557560-11Dual RJ45 Jack RA
JP1Molex10‑89‑70420->1Jumper block, 0.1", 2x2
TB1Phoenix ContactMSTBA 2,5/2-G-5,08 P/N 17572420->1Terminal Block Header, 2 pos, 5.08mm
Phoenix ContactFKC 2,5/2-ST-5,08 P/N 18730580->1Terminal Block Plug
Molex15-29-10250->2Jumper, 0.1""


  • Get the PCB made at your favorite PCB fab. Some will take Eagle files; almost all take Gerbers. I do not provide Gerbers because different PCB makers have different standards.
  • If you do not need to provide external CAN_V+, you can skip JP1,TB1, the terminal block plug, and the jumpers.
  • Terminal Block Plug: you can use any terminal block plug that fits into the header. I used a spring clamp model (1873058).
  • You can also used a fixed terminal block instead of the removable terminal block system I used. Some 5.08mm fixed screw terminal blocks have compatible PCB footprints.
  • Assembly should be easy - this PCB requires only standard through hole soldering techniques.