lwright wrote:Hey,
I was going to use a amp guage instead of a charging light, I guess it would work the same.
Larry, an ampere meter (guage) would need to go in the output line from the alternator to the battery to function properly.
Alternator setups these days typically don't use a guage, though I think it will work fine if wired in properly. Alternators do need the field coil energized from the battery to start charging. (they will 'self energize' once they get going, but they need that 'kick' from the battery to get 'em started) .
The idiot light (indicator light) serves two purposes....one is a bit of resistance in the circuit, the other is more apparent....a visual indicator that the alternator is charging properly.. or not. The wire to the field coil should be switched....else you will drain the battery when the tractor isn't running. If you don't wire in a light , you will almost certainly need to add a resistor to get some resistance in the circuit. You may have to regardless... many cars use a 'resistance wire' for this purpose.
The voltage sensing feature isn't found on some alternators, especially some of the older ones or those made for certain ag or construction equipment.. It's been common on cars for a long time....it's purpose is to adjust the alternator output voltage to compensate for voltage drop in the wiring.......in other words, to make sure you get proper voltage (approx 14) at the battery terminal or main junction in the wiring harness...this may require the alternator to produce 15 , 16 volts or higher at the output lug.
You can get by ok without this on most tractors....they typically don't have many lights or other load on the electrics........if you add a bunch of work lights, an electric sprayer, or some other big electrical load, you'll find it a very handy thing to have.
If you get stuck, give me a holler...I can find some time to come up and give you a hand .....
