I'm at the point in my Electra project where I need to wire the motors and speed control. What size and/or type of wire and connector is appropriate?

I've got a bunch of orphaned servo wire and connectors (standard, full-sized stuff from the olden days before things got so small and light) and I'm wondering if I can use it for the motor wiring. The connector that came with my Sirius 200 charger looks suspiciously like a full-sized servo connector. Any recommendations?

From : Don Stackhouse

Old servo connectors will work fine,although you need to be careful that you don't accidentally mix up the connector from the ESC to the radio with the connector to the battery. There's a very nice 2-wire JST connector that Hitec sells that I use for my standard connection to the battery. It's compatible with the connector on the Sirius charger, with the connectors that come installed on our NiMH battery packs, and with a number of other common connectors.

We normally hard-wire the lines from the ESC to the motor, a connector in that part of the circuit is just extra weight and power loss, and unnecessary extra failure modes.

As far as wires are concerned, the gauge of the battery wires on the ESC are a good guideline. 22 or 24 ga. servo wire works fine. I even used 27 gauge wire on the wiring for all four motors of our prototype B-17 with no problems. The motors are all in parallel with the ESC wired to the middle of a bus line along the leading edge. In the legs to the individual motors (and in the wires to the motors of your Electra), the current is typically slightly more than than 1 amp at the most, and even in the bus lines of the four-motor model the current is normally under about 2 amps, so it doesn't take very thick wire to handle it. In any case, the current in any of the motor wires is certainly less than the max current in the lines from the ESC to the battery, so the wires supplied with the ESC for that line are sufficiently big for any of the other leads in the circuit.

Don Stackhouse
DJ Aerotech