Just purchased a new 3 way battery switch and I'm a little puzzled by the 2 field terminals, can anyone advise what they do and do i need to wire them in
The purpose of the two poles is to enable the switch to cut off the current from the starter key to the field terminal at the same time as the connection betwen the alternator and the battery is cut off, therefore the alternator no longer produce any electricity and you don't risk frying the diodes if you accidentally switch to "off" whilst te engine is running. Just connect a wire from the alterntor's field terminal to one pole and another from the starter key to the other pole.
john