Newbie to vw T3. How the batteries work???

chipsandsmash

Free Member
Posts
10
Likes
6
Just got our project van. Its a t25 1985 camper
Never had a leisure battery or shore power thingummy before .
The van needs a new engine which we'll be getting put in, in the spring.
so it needs to sit for 10 weeks .
OH will start it up a couple of times a week till then .
My question is ...
If I plug it into the house power with a hook up cable, does it charge the leisure battery only or both drive and leisure battery?

We've got a battery charger which we can use to charge the drive battery if not.
 
Hi, many more knowledgeable than me but I know if you plug the sale trip hook up into mains, it charges the leisure battery. We charge the engine battery with another charger. Don't know if some are linked but that what our van has.
 
The charging on your van will depend on how whoever built it wired it up, to check which batteries are being charged you will need to put a meter across the battery terminals (or wiring connected to them) with the charger on.
 
Simple job as mine is done, use a 200ah relay from engine bat to less bat with a switch to connect when driving, but also to switch on when on mains so the charger will do both, also use a 3/5 stage smart charger, make sure you use a mains trip unit & polarity change over switch as many campsites are wired in reverse.
switch.jpg
200ah relay.png
 
Vans can be wired differently, and some systems have switching options.

Best thing is to check the voltage after the van has been parked up for 1/2 hour without EHU.
Connect EHU and after 10 minutes recheck.
 
you have to have a basic meter-you'll use it a lot! check the voltage when van isn't connected to 240v , then check it again when it is . it should read around 12v at first . when connected to charge , 13-14 v . if it does ,it's charging ,if not , it ain't
 
you have to have a basic meter-you'll use it a lot! check the voltage when van isn't connected to 240v , then check it again when it is . it should read around 12v at first . when connected to charge , 13-14 v . if it does ,it's charging ,if not , it ain't
12.7 for a good battery 12.2 if down, then 14.4 when full at peak of charging before falling back to 13.7 on float charger.
 
Battery cable through a 200ah relay, hence I can also use for starting if engine bat down.
I assume you mean 200a relay. 200ah relay is a meaningless.


It seems a bit low, starting can require 500+ amp, and batteries are typically capable of 800 -1000 CCA.

You still need thick wire from the battery to the relay and from the relay yo the starter motor.
 

Users who viewed this discussion (Total:0)

Back
Top