hi i have a new controller on the way. my question is it has got 2 red wires plus 1 black wire on the power socket black is neg thick red is positive 48v but what is the thin red one for ? and how many volts does it require? also i have 2 wires from my brake but this controller only has 1 wire hope some one could help cheers.

The thick red wire is the positive power-in, the thin red wire is the positive supply-in for the controller, and the black wire is the common negative. These wires should connect ur battery. If ur battery just have 2 wires, ur can connect the thick and thin red wires together. Be careful, if the negative and the postive are changed, the controller would be burn.
U must make sure ur controller's brake sign. Commonly, 48v controller is "negative". It means if u "brake", the sign connect to the negative. So u can connect one brake wire to the negative, one wire connect to the controller.

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