The Pre-charge Resistor is placed on the 5/16" or 3/8" studs and can be placed either direction as it is bidirectional. This is used to keep the controller capacitors charged so there is not a large current surge through the contactor each time the contactor closes. This will increase the life of the contactor as well as the capacitors in the controller.

The coil of the contactor is also bidirectional and you only need to make sure that the diode is on the right way. The white band on the end of the diode called a cathode should be on the same side as the red heat shrink. Both the red heat shrink and cathode should correspond to the #1 on the Alltrax drawings and the hot side of the circuit comes from the foot switch on a series cart or from the key switch on the shunt carts. Alltrax Diagrams