Generator/Alternator cable rating

[gav]

Thanks Steve - thats really helpful

So if I am running circuits that draw power from the alternator through the existing wiring loom, they will continue to run and if that exceeds the charge that the battery needs, the second cable will essentially top up the missing portion.

On this basis, the battery should never go flat even if the other circuits are taking all of their allocated power.

Does that sound right?

This doesnt deal with undersized cables, nor circuit mods over the years but would allow the stsus quo to remain in the interim.

Thanks
Gavin

[steve lyle]

I think you’ve got it.

In my experience the original loom isn’t bad. When I rewired my car, I did find a significant benefit to upsizing the window motor wiring - doing so dramatically increased the lift/lowering speed. I also upsized the power wire to the headlights/horn and radiator fan.

[gav]

Many thanks Steve

Lots of food for thought

[gav]

Ive been doing some homework.......

...and discovered that my auto electrician joined 3 cables (colours yet to be confirmed but one is definitely the original brown battery link from the control box to the solenoid). One of the cables is a newer 44 strand / 0.26 mm cable which I think equates to 2.4mm sq or 14 gauge providing around 25A. This is what is connected to the alternator alongside the cable from the ignition switch which includes the ignition light. I dont seem to have any exciter cable to the alternator but it does seem to work so presumably I dont need one.
I will expose the junction where these old control box cables have been joined but my instinct is to abandon the newer 25A cable to the alternator that sprouts from that soldered joint and replace it with a much higher amperage one direct to the battery via the solenoid connection.
I plan to retain the brown cable that used to run from the solenoid to post B of the control box because I suspect that it still feeds the original circuits and with luck I will be where I need to be.
Hope this makes sense and happy to take thoughts as to the logic.
Thanks
Gavin