Re: 1937 120C Current Draw

Posted by humanpotatohybrid On 2023/12/26 13:57:57

If you have only two relays the one with the thick wires will be the circuit breaker AKA cutout relay. Actually the cutout relay has two windings. The shunt (meaning the other side is connected to ground) winding of thin wire pulls the contact in when the requisite voltage is reached. The series winding of thick wire increases the strength of the magnetic field when the cutout relay is closed, to provide hysteresis.

The cutout relay should be open with the engine off or at low speeds. You should see it connect when the engine is revved up and disconnect at a slightly lower RPM. This can easily be checked with a voltmeter...