Alternator Wiring Question
If you actually want to see whether the battery is charging, then you need to wire the system like Chrysler did with a seperate leg for the battery charge/feed. The ammeter in this leg of the circuit will show if electrons are flowing into or out of the battery.
How this works^^^
Imagine the engine is off. Turn on the headlights. The electrons flowing through the ammeter create a small magnetic field causing the needle to swing toward discharge. Same if the engine is running and the alternator is not working.
If the alternator is working, after start up, the needle swings toward charge until the battery is full.
If you just want to know if the system is running on the alternator vs. battery power, then a voltmeter will do the trick. It will show whether the system is seeing 14+ volts or 12.5 ish volts at whatever location you tied it in.
I would tied it into the run or the switched accessory circuit so it is only on when the key in run or accessory.
Interesting choice of a Ford alternator. Don't see or read about using Motorolas that often. Put a photo we can get a better sense of what you're dealing with. Chrysler actually used Motorolas a very little bit - I saw a reference in the Hamtramck Historical Library - maybe for postal delivery trucks one year. in the late 60s. I'm sure that's not what you ahve.
If you actually want to see whether the battery is charging, then you need to wire the system like Chrysler did with a seperate leg for the battery charge/feed. The ammeter in this leg of the circuit will show if electrons are flowing into or out of the battery.
How this works^^^
Imagine the engine is off. Turn on the headlights. The electrons flowing through the ammeter create a small magnetic field causing the needle to swing toward discharge. Same if the engine is running and the alternator is not working.
If the alternator is working, after start up, the needle swings toward charge until the battery is full.
If you just want to know if the system is running on the alternator vs. battery power, then a voltmeter will do the trick. It will show whether the system is seeing 14+ volts or 12.5 ish volts at whatever location you tied it in.
I would tied it into the run or the switched accessory circuit so it is only on when the key in run or accessory.