12 volt regulator

55 50 Ron

Well-known Member
Been "analyzing" a new regulator. Not connected to anything, just photographing it and making some ohm measurements.

F terminal to chassis 57 ohms with internal contact open. That's the wire wound resistor built in. point 2 ohm with internal contact closed.

Gen terminal to chassis 37.8 ohms and stays the same regardless of other contact positions. This seems to be the Field relay winding's resistance.

Bat terminal to chassis "open" with "cutout" relay open. 37.8 ohms with "cutout" relay closed.

This is a positive or negative "ground" unit.

Hope this may be of some use to those doing their own electrical troubleshooting.

You other "sparkies" chime in with additions, OK?

Thanks
 
"Gen terminal to chassis 37.8 ohms and stays the same regardless of other contact positions. This seems to be the Field relay winding's resistance." You are also measuring the resistance shunt or "pull-in" relay coil in the cutout section.
 
Ron those values seem reasonable. The field control relay modulates how good of a ground the fields get (from gennys FLD post to ground) and low to no ohms would allow for max high charge, while it can cycle n chatter the other ohms to regulate the net resistance (from FLD post to ground) for a lesser charge.

There has to be a shunt winding in the cutout relay to provide a path from the gennys ARM output to ground in order to latch in and close the cutout relay contacts (located between BAT and ARM) once the set voltage is achieved. That's the 37.8 ohms is my guess NOTE HOWEVER I dont view that 37.8 ohms as being what you call "Field relay winding's resistance" I view it as the cutout relays shunt winding resistance. There's also a series coil in the cutout relay circuit which is the bigger wire

John T
 

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