Quote:
Originally Posted by wireties
The best connectors have a profile similar to the diameter of the wire. The reflections occur at impedance mismatches and the impedance of the connector is largely a function of the geometry. In an ideal world the wire and all the connectors would have the same impedance at 1Mhz and the terminations at each end would be 2X that impedance, nominally 50-60 ohms for CAN. Note that this is impedance, not purely resistance.
We have used PWM connectors and Molex connectors (for 20AWG wire) with zero issues running 9 Talons. Powerpole pins are overkill for the current and are larger than 20AWG wire - I would shy away from using them.
Good luck!
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We are looking at using the locking PWM connectors from Hansen Hobbies. They use different contact pins than the "normal" PWM connectors they sell but the same crimper can be used. Like the PWM connectors commonly used in FRC, they have a physical configuration that is more similar to the physical configuration than most of the small connectors I have found (and many of those suggested in this thread).
The 30A and 45A Anderson connectors can work for the CAN Bus connections but will probably present a larger disruption to the characteristic impedance than the PWM connectors. They are also meant for minimum wire sizes of 16AWG and 14AWG, respectively, so extra precautions will have to be taken to ensure a good electrical and mechanical connection is made. It is also likely that people pull on the wires to un-mate the connectors. While the 16AWG to 10AWG wire that is normally used might survive this type of abuse, the 22AWG CAN Bus wires that are part of the motor controllers will be more likely to be damaged.
I have used my industry contacts to find a small connector for the CAN Bus connections but have yet to find a better solution than the parts from Hansen. The parts I was able to find either required the purchase of a special tool from the connector manufacturer (typically $100's) or were rated for an unacceptably low number of mating cycles (i.e. 25 vs 10,000 for the 45 A Anderson and others). It would be best to check the tooling required and the mating cycle rating before committing to a connector type.