Controller Area Network Bus Termination resistor

[jbc57]

Hello all,

I'm looking for a standard automotive CAN Bus termination resistor to implement in a wire harness. I know that a 120 Ohms resistor is needed at each end of the bus to isolate it from noise. I have 3 nodes on the bus and only one is terminated. Since this goes for several units, welding a standard resistor between the 2 cables is not acceptable.
Therefore, if you have any clue on connectors featuring such termination or anything else, it would be really appreciated.

Best regards,
JB

 

[itsmoked]

I have not used CANBus but are you sure you need a terminator in the middle??? Normally you only use terminations on the ends of cables as they are to prevent reflections from the ends.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[felixc]

There are several CAN cable implementations possible. What is yours? A shielded twisted pair? What is the environment in which your cable works? Can you use a 2-pin IDC connector and crimp it at the end of your cable. Find the mating 2-pin header and solder the resistor to it. That lets you plug it on or of at will. It becomes more touchy if the environment is tough.

 

[jbc57]

My CAN cable is not shielded, it's a twisted pair. This Bus is designed to work in harsh environments such as truck frame.
Do you know how this termination is made in OEM CAN networks?

Thanks again.
JB

 

[felixc]

Well, the systems that I've done integrating CAN had their own termination resistors, permanently connected in the case of the master controller, and software switchable on the slave modules.

How is your cable connected to your present modules? Can you identify what these connectors are? Use a connector set of the same type, and place a resistor at the mating end.