Going to IC reg alt (1 Viewer)

[Quat]

Hello,

I'm swapping to an internally regulated alt from an external on an '89 HJ61. As best I can tell from the wiring diagrams, both internal and external regulators 'sensing' wires run back to the battery directly. However, most the threads I've seen seem to indicate they tied the 's' wire to the ignition/engine fuse circuit. Is there a reason for this?

I makes sense to me for the new alt to be plugged IG->IG on the old mechanical harness, S->B, to avoid reading the voltage draw from everything using power on the ENGINE circuit as battery voltage, and L->L, but maybe I am missing something.

Thanks.

 

[FJ40Jim]

Sense wire should be connected to battery positive so alt can accurately charge battery.

It's easier to connect the sense wire to a 12V wire, so some people do it that way.

 

[Quat]

Thanks. The b wire is 12v (24v in this case), so i wasn't sure if there was some special reason to change the wiring around to have 12v on an ignition switched wire.