I know there has been a lot of wiring questions lately so I hate to pile on with another but here goes. I posted last winter that I was setting up an M that I got in disrepair on a 12V system. I kind of walked away from it for a couple of months and forgot what was what. It is a 39 M with magneto ignition, a 4 post VR, set up for 12V. The gen shop set the generator and VR for 12V. The following is the way that they told be to wire the tractor. Wire from gen post of VR to ARM post of gen. F post of VR to F post on gen. L post of VR to left post of ammeter. Batt. post of VR also to left post of ammeter. Cable from negative post of battery and wire from right post of ammeter to top post of the starter button. Cable from bottom post of starter button to post of starter. Cable from positive post of battery to tractor frame for a ground. Does this sound right? I looked at Farmall Bob's diagrams and didn't see anything for a magneto ignition with 4 post VR set up on 12V.
- Thread starter Baelee05
- Start date
SadFarmall
Member
Yes, it all sounds good. Principles of wiring are:
Main Terminal of Generator to Main Terminal of Regulator (labelled D or Arm for Armature)
Field Terminal to Field Terminal (labelled F)
The ammeter sounds fine also. The way you have it, the worst that you might do is have the ammeter read backwards. If this happens, just reverse the connections on the back of the meter.
You can't really go wrong with the ammeter unless you do either of:
1). Connect it direct from negative terminal of battery to Earth - will probably set the ammeter on fire
2). Connect starter motor circuit through ammeter - also liable to cause copious release of smoke when you hit the start button
Main Terminal of Generator to Main Terminal of Regulator (labelled D or Arm for Armature)
Field Terminal to Field Terminal (labelled F)
The ammeter sounds fine also. The way you have it, the worst that you might do is have the ammeter read backwards. If this happens, just reverse the connections on the back of the meter.
You can't really go wrong with the ammeter unless you do either of:
1). Connect it direct from negative terminal of battery to Earth - will probably set the ammeter on fire
2). Connect starter motor circuit through ammeter - also liable to cause copious release of smoke when you hit the start button
Janicholson
Well-known Member
In the generator and science sense it is a place where magnetic lines of force (a field of magnetism) is produced to allow spinning wires in (an armature in a generator), or stationary wires, (the stator in an alternator) can generate electricity bu passing through the field, breaking the lines of force and pushing electrons down the wires. Jim
TractormanNC
Member
One change should be made. wire from the L terminal of the VR should go to the light switch and the ignition switch IF you had battery ignition. This connection lets the VR respond to the batterys state of charge without being affected by the light and ignition load.
Janicholson
Well-known Member
Ignore the magneto. It is not a part of the charging system and has no connection do not connect it to anything leave it as is. They cannot be connected successfully to any source of voltage. Jim
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