I just bought a regulator/rectifier from baja designs. I am going to make some DC power with a ni-cad I bought to run my GPS unit. I have a question about the regulator/rectifier. I thought it would only have 4 wires, but came with 5. I am not sure what to do with the 5th wire. I know the two yellows go to the stator, the red to positive battery, black to ground, but where does the blue go??