3 4 terminal voltage regulators for H Farmall

My H has a 3 terminal voltage regulator. The replacements seem to be 4 terminal. Can a 4 terminal be used in place of a 3 terminal? What do you do with the 4th terminal? There is no place to hook it up. Thank you.

YES,,,,,,,,,,Its possible to change from a 3 to 4 or 4 to 3 terminal VR with only minor wiring modifications:

NOTE on many 4 terminal VR"s the terminal on the bottom or on one side all by itself is the ARM terminal while BAT FLD LOAD are together side by side.

First, you can use the 4 terminal and simply ignore and dont use the (L)oad terminal as the Loads its designed to feed hot battery voltage to are already fed such from the Load side of the ammeter. Thats the cheap n easy way, just dont use L........

HOWEVER to get the advantages the 4 terminal VR has to offer Id use its (L)oad terminal wired as follows:

BAT on VR up to Load (NOT battery/starter) side of the ammeter. Same as how the 3 wire is already connected, you can use the existing wire as thats where its already wired to.

FLD on VR to Gennys FLD post, same as 3 terminal VR is connected. Just wire it instead to FLD on the new VR

ARM on VR to gennys ARM post, same as if a 3 terminal, just wire it to ARM on the new VR

LOAD on VR wires up to the dash (a new wire is required) to supply hot battery voltage to loads like lights and ignition (via a wire to the switches BAT INPUT terminal). You would remove and do away with the wire now from the ammeter to supply loads (lights and ignition switches) and replace it with a new wire from L on the new VR. I.E. The wire now connected to the load side of ammeter that feeds hot voltage to the switch is removed from the ammeter and wired instead (longer wire and a splice required) down to L on the new VR

If I missed something the other gents can corect me I hope.

John T

I have a 4 terminal VR on an H. I converted it from the old cut-out relay which was no longer useable. I used the 4th terminal on the VR to power up the lights.