Repairs and upgrades for the charging system
The shunt is 360 brass. Less conductive than copper.
.035 thick, .490 wide, and .890 active length.
I started wider and reduced the width for calibration.
Ohm's law for parallel resistors will get you very close. The OEM ammeter is not terribly precise, I measured 3 different ones and got different readings.
Obviously you will need a Wheatstone bridge to measure the very low resistance ammeter & shunt.
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