MoTeC Global Forum

Just wondering what people do when it comes to wiring outputs using 2 pins, do they :

a) run two individual wires from each pin on the PDM connector to the device and then then join them at the device or device connector, or

b) run very short wires from each pin on the PDM connector to a splice, and then run a large gauge wire to the device.

c) something else

My intention is to use M22759 Tefzel wire throughout, 22 AWG for switches and CAN bus, 20 AWG for 8 AMP outputs and 16 AWG for the 20 AMP outputs.

Regards
Toby

I normally do B, but might do A if the run was short enough, or I needed the cable to be more flexible.

I vote B also.

Those "short runs" are usually something like 200mm to 300mm. This way it is easier to make the loom neat.

As David said, you can do either A or B, dependant on a number of factors as he mentioned. I will use both methods in cars that I work on, choosing which type I do based on the circumstances faced.

I am in the middle of wiring mine and will be using a combination of both methods. I am cabling the PDM out to a number of panel mount DT connectors and given that the pin rating on those is 13A I will be running separate wires per pin for the 20A outputs through the panel mount connector then brining them together to a single conductor for the main run, breaking them out again for the wiring to the rear of the car which will go to panel mount DT connectors again.

Done that way I hope to keep the cars wiring fairly modular with everything plug in in as many places as possible rather than running fixed cabling through grommets.

Thanks for the comments everyone

Do you use 20 AWG wire from each of the two 20 AMP output pins, then combine these using a single 16 AWG for the main run through the car to the device being powered ?

Lastly is there a PDM wiring FAQ in existence ?

It would depend on how much current you actually expect it to carry. If you expect to see the full 20A then that might be underdone, Admittedly it is at 80 degrees but MoTec list #16 wire as being good for 15A (12A at 100 degrees) I was going to run #18 or #16 wire form each pin and then consider what to do from there according to expected circuit current. Anything needing near the full 20A I was going to keep as two #16 wires end to end.

thanks

Sounds to me like it may be easier to use #20 or #22 on every input pin and #16 on every output pin all "end to end" wires, seeing as all 8 AMP outputs are catered by #16 wire (well over 100 deg C) and 20 amp outputs all use 2 pins and again cope with over 100 deg C. I have the odd 8A output which is literally only using 1 amp but in the interests of the KISS philosophy I'll keep them all the same!