Hello,
Does anyone know what is the correct type and gauge of wire to use for my CAN bus? I did some research and it appears that shielded twisted pair is recommended. Are there any special connectors to use where additional devices are connected to the bus?
Any idea where to buy the correct wire and connectors?
Thanks
CAN runs at a speed which does not exceed 1MHz. Also, it does not need a lot of current. The wiring size in a car is usually something like 18ga but mostly for strength reasons. You could run it on 28ga wire if you wanted to. But, that small of a gauge is weak and breaks easier. You do want twisted pair wiring if you can help it. The slow speed means that you don't need anything too crazy for wiring. At faster speeds you need special wire which is why ethernet uses CAT5 or CAT6.
Usually CAN terminates into each device on the bus in something like an ampseal or other automotive connector but there isn't any one standard way of doing it. For connecting multiple devices on the bus a lot of vehicles have a junction box somewhere centralized. Or, they pass through each device such that the device has four CAN wires, two in, two out. The best bet is to keep your taps as short as possible. This is easiest when you do the pass through the plug approach. The longer your CAN bus the more you are asking for trouble but it should be fine if it ends up being 30-40 feet.