I figured it would be a good idea to check the function of all the major components, so yesterday I hooked up the motor, controller, contactor, throttle, and one of the batteries. I have not yet purchased the main power cables, so I had to make do with whatever spare lengths of monster cable and bits of 18 ga wire salvaged from previous LED and cold cathode lighting projects. I also haven't purchased the switches yet, so some of the final contacts were made just by touching a wire to the contactor lead (this will be a keyswitch that initiates main power) and then touching two more wires together (this will be a rocker switch to engage forward or reverse motion). This probably wasn't the safest approach, but it was good enough.
After some fiddling, I finally got the motor shaft to turn, both forward and in reverse. (My creation LIVES!!! Bwahahahaaa!!!) I spun it up to full throttle, and didn't have any problems with the BMS of my 20 Ah YESA battery cutting out due to high current draw. But keep in mind that this was under no load, after all.
Two important things I learned through this exercise:
1) I will need a separate switch to engage forward motion after I engage the main power and before I start turning the throttle. If I turn on the main power while the forward switch is engaged, this results in a controller fault message. I was hoping to just be able to turn the key, twist the throttle, and go, but I suppose pressing one more button to engage the drive isn't much different than pressing the starter button on my ICE scooter.
2) THERE IS A MISTAKE IN THE WIRING DIAGRAM that was included with my controller. http://www.teamdelta.com/products/prodimages/Millipak_PMAC_Controller_Wiring.pdf This took me a couple hours to figure out. Beware of this error if you are using a Sevcon Millipak SBPM controller. I don't know if this one-page diagram was produced by Sevcon or someone else, but the wiring is shown correctly in Sevcon's user manual. Basically, the throttle lead should connect to pin 10 on the molex connector instead of pin 11, otherwise you will get an "accelerator wire off" fault message from the controller.
Now I need to fit all these pieces in the scooter and figure out how much 4 gauge wire to buy. At $3.50 per foot for the stuff, I don't want to get much more than I'll really need.