Alternator terminals - an alternative for D+

[tillergirl]

I have a Perkins 6.354 with a CAV 24v Alternator with separate regulator. I want to fit a Battery to Battery charger but it requires, inter alia, a D+ connection.

The regulator choices are: - A WL F Hi Med Lo

Hi, Med, Lo are the equivalent to B+; that's clear. WL is for Warning Light so I am assuming that is equivalent to D+. But I have found a couple of wiring diagrams but they are not definitive - one says the WL is for the warning light, another uses A for the warning light!

Does anyone know please?

 

[superheat6k]

This might help you ...

https://www.dropbox.com/s/c3ke2yeiq39wvqf/alternator handbook.pdf?dl=0

 

[tillergirl]

Thanks. It's interesting about how alternators work but it doesn't address 'WL'

Grateful for the background though.

 

[Surfacesub]

On the basis of the information provided it sounds like you have the AC5 24V alternator with the remote regulator.
In which case the alternator also has a 'A' terminal which should be connected to the corresponding terminal on the regulator.
I could elaborate further but suffice to say the 'A' and 'WL' terminals are connected together inside the regulator.
When the alternator starts to output the potential of 'A' terminal ramps up to provide a separate source for the regulator and 'WL' light and at which point the warning light will extinguish as the potential on either side of the lamp is approx. equal.
Providing any additional load applied to either terminal therefore is negligible which relays in general are, your paralleling charger will function correctly when connected to either.
To confirm the above and to ensure I have understood you correctly, check using a multimeter set for 24v DC at each state of start up.
With the regulator in isolation you could also check the 'A' and 'WL' terminal have zero resistance between them to prove they are in your case connected together.
I have a spare sitting on my desk and can confirm the multimeter result agrees with my wiring diagram. i.e. connected together.
I hope this help you.

 

[tillergirl]

Thank you. Yes AC5 24v with remote regulator. The Alternator has no terminals external, just a 'loom' of wires which goes to the regulator. Both A and WL terminals on the regulator are 'occupied' (as others are as well of course). When I go on board tomorrow I'll check the 'zero resistance' check. It looks that the battery 2 battery charger sense wire can piggy-backed onto the WL.

Very grateful.