Round back to square back alt
While I'm rambling on about this, lets take the same example, with the same resistances and exchange the factory alternator with a 2.5 amp field current draw, for one that draws 7.5 amps.
V=IxR
Voltage drop to the regulator with the factory alternator drawing 2.5 amps and the ignition drawing 2.5 amps was 0.3 Volts
.3 V = 5 amps x Resistance
Resistance = 0.06 ohms
New alternator increases the current in the ignition circuit to 10 amps
V = 10 amps x 0.6 ohms
V = 0.6 Volts
So here's how that plays out on the diagram of a battery recharging at 20 amps.
This is just to illustrate the relationship between current and voltage drop caused by the resistances to that current.
Generally we'd expect the most voltage drop in the connection at the bulkhead with highest current flow. And in fact this one of the locations we often do find heat damage. But all of the connections are vulnerable, and those exposed to weather, and engine heat, as well as wear (key switch) can develop problems over 50 years.
While I'm rambling on about this, lets take the same example, with the same resistances and exchange the factory alternator with a 2.5 amp field current draw, for one that draws 7.5 amps.
V=IxR
Voltage drop to the regulator with the factory alternator drawing 2.5 amps and the ignition drawing 2.5 amps was 0.3 Volts
.3 V = 5 amps x Resistance
Resistance = 0.06 ohms
New alternator increases the current in the ignition circuit to 10 amps
V = 10 amps x 0.6 ohms
V = 0.6 Volts
So here's how that plays out on the diagram of a battery recharging at 20 amps.
This is just to illustrate the relationship between current and voltage drop caused by the resistances to that current.
Generally we'd expect the most voltage drop in the connection at the bulkhead with highest current flow. And in fact this one of the locations we often do find heat damage. But all of the connections are vulnerable, and those exposed to weather, and engine heat, as well as wear (key switch) can develop problems over 50 years.