westy second battery wiring question

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germansupplyscott
Posts: 887
Joined: Fri Jul 20, 2001 2:01 am

westy second battery wiring question

Post by germansupplyscott » Mon Feb 04, 2002 12:38 am

gents,

this is for anyone who has a factory second battery in their westy, and knows how it works. mine is a 1979, with what is what I THINK is a factory second battery. the battery was not getting charged by the alternator, so i needed to investigate. the battery will charge fine with the timer if you are connected to shore power, by the way.

tonight i was looking at things and testing voltages to try to figure out how it is supposed to work. in theory, i think the two batteries will be connected in parallel when the motor is running, allowing the alternator to charge the second battery. once the motor stops, the relay should disconnect the two batteries, so that you don't drain the main battery with your sony playstation at the koa...

well, i can't figure out how to make it work. maybe someone else has this same setup that actually works and can talk me through the right way to connect things.

tia,

scott lyons

Andreas Mann
Posts: 6
Joined: Mon Nov 26, 2001 3:01 am

westy second battery wiring question

Post by Andreas Mann » Mon Feb 04, 2002 4:32 am

Hi,
I already don´t have a second battery in my bus but I know that you need a relay (?, is it the right word in english?). I have one and a friend of mine already installed it and a second battery in his bug.
This "relay", a small black box switches when the first battery is charged enough it will charge the second. If you need the partnumber (BOSCH or HELLA) or the wiringplan I can mail it to you.

Andi
amann@mac.com

Andi

tomt
Posts: 736
Joined: Fri Nov 03, 2000 3:01 am

westy second battery wiring question

Post by tomt » Mon Feb 04, 2002 9:47 am

The bus depot http://www.busdepot.com lists a dual battery relay kit for $18.95 item number 1738.

You will probably save yourself a lot of time and headaches by just replacing the old stuff with new...

I am not affiliated with the Bus Depot in any way, but I am a satisfied customer.

germansupplyscott
Posts: 887
Joined: Fri Jul 20, 2001 2:01 am

westy second battery wiring question

Post by germansupplyscott » Mon Feb 04, 2002 10:51 am

andreas,

if you were able to email me the wiring diagram, that would be helpful. i think the parts i have are good, only that they are not connected properly.

thanks,

scott lyons

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Hank Winning
Posts: 608
Joined: Sat Nov 10, 2001 3:01 am

westy second battery wiring question

Post by Hank Winning » Mon Feb 04, 2002 12:16 pm

Scott,
A marine divi-charger (battery isolation diode) hooked up to your alternator will charge both batterys and keep them seperate.
No moving parts like a relay.
We have installed many with no problems
best wishes
hank

germansupplyscott
Posts: 887
Joined: Fri Jul 20, 2001 2:01 am

westy second battery wiring question

Post by germansupplyscott » Mon Feb 04, 2002 4:32 pm

hank,

like i said in my post, all the parts i need are there, i just need some assistance in setting it up. the way it is now, there is not hot signal to the relay, so it can't switch the 2nd battery on and off, i am looking for a circuit diagram of the original set-up or verbal guidance on what the original circuit would have been. the van has had some reworking electrically by the PO and i'm attempting to put it back to the way it was.

as for the diode deal, it sounds like a good solution: where does it go in the circuit and how much does one (aprox) cost? i'll call genco marine today, but my experience with anything from a marine store is that it costs too much. yachtsmen are not poor, unless their boats make them so...

scott lyons

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Bob Ingman
Posts: 2869
Joined: Mon Mar 19, 2001 3:01 am

westy second battery wiring question

Post by Bob Ingman » Mon Feb 04, 2002 8:05 pm

scott, I just checked type2.com for you and found good info there. look under library then click on to electrical primary then scroll down to dual battery relay installation and next to it wiring diagrahm for dual batteries this should get you going in the right direction
. Bob

rich2481
Posts: 1539
Joined: Tue Dec 18, 2001 3:01 am

westy second battery wiring question

Post by rich2481 » Tue Feb 05, 2002 12:45 am

Scott, when I have time this weekend, I will search the Haynes manuals I have and see if it possibly has the wiring diagram that you seek.

Rich

germansupplyscott
Posts: 887
Joined: Fri Jul 20, 2001 2:01 am

westy second battery wiring question

Post by germansupplyscott » Tue Feb 05, 2002 12:48 am

hank, bob, rich, et al,

with all the responses, as usual the vw community has come through big time, and i now have what i need.

special to bob,

i am such an advocate of the type2 library, i point people there all the time, and this time i had a brain cramp and didn't look there first, like i usually do.

thanks all,

scott lyons

ray greenwood
Posts: 1941
Joined: Thu Jul 19, 2001 2:01 am

westy second battery wiring question

Post by ray greenwood » Tue Feb 05, 2002 7:37 pm

Thank you all...! I was asking the same questions a couple of months ago as my 412 originally had an option for twin batteries (m558 option ...or something like that). What you are refereing to is call a battery isolater unit. You can get them at most auto parts stores by the battery cable section. The problem is getting the correctly sized one. I was wondering if it worked as well as the relay method used by the factory. Again thank you all for answering a question I did not ask. Ray

papun5880pr
Posts: 245
Joined: Mon Oct 29, 2001 3:01 am

westy second battery wiring question

Post by papun5880pr » Tue Feb 19, 2002 11:24 pm

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Andreas Mann:
<B>Hi,
I already don´t have a second battery in my bus but I know that you need a relay (?, is it the right word in english?). I have one and a friend of mine already installed it and a second battery in his bug.
This "relay", a small black box switches when the first battery is charged enough it will charge the second. If you need the partnumber (BOSCH or HELLA) or the wiringplan I can mail it to you.

Andi
amann@mac.com

Andi</B><HR></BLOCKQUOTE>

i need the wiring and details for the second battery on my bus.if you kindly can send them i'll appreciate it;danny
papun5880pr@aol.com

Derek May
Posts: 217
Joined: Tue Oct 02, 2001 3:01 am

westy second battery wiring question

Post by Derek May » Sat Feb 23, 2002 3:18 pm

Punkin:

I've two batteries, factory setup, original gear and it works.

Find the relay, and follow the wires back to source. Essentially, there should be 4 wires. One wire is a ground, that's easy to sort out. Another wire goes to the second battery, positive terminal. Should be able to follow that. Another wire goes to the primary battery on mine, its just clamped into the positive lead that comes from the alternator to the battery on mine. It did something more complicated, but didn't work and this is what I did to fix it.

Last wire is the one that operates the relay, and it needs wired in so that it is hot only when the ignition is on. My relay was wired in properly so I didn't need to rewire that lead, but that lead can be connected to any wiring that meets that criteria .. use a voltmeter to find a lead in the engine bay that works that way.

Testing should show current through the relay when the ignition is on, but not so when ignition is off. It is operated by engaging ignition, not by running of engine.

On my van, the relay is mounted on the driver's side, near the tailight. There are 4 connections. 2 are to the back of the van, the one next to the left is the ground, its brown in colour. the one to the right of it connects the wire that is hot only when ignition is on, its black. the one towards the front of the van, in the front left corner of the relay connects to a red wire going to the second battery, the last connector is sort of in the middle of the relay, and connects to a red wire going to the primary battery. The two read wires are pretty heavy gage, if you are wiring with new wires, I'd suggest the heavier the better, but they are not the size of the leads to the primary battery by any means, small enough to fit into a crimp connector. The hot wire (black) and the lead to the primary battery (heavy red) are both encased in a black plastic sleeve that is directed across the top of the engine bay to the primary battery side. I'm not sure where the black lead goes ... as I said, it worked on mine so I didn't need to track that down, the problem was the red lead which I had to rewire to the primary battery.

You can rewire with fresh leads if your wires are missing or if this is a fresh install, and the important thing is the heavy reds between the batteries across the front connectors, the ground, and the wire to any wire you can find which is hot only when the ignition is on.

Hope this helps.

Derek May
Posts: 217
Joined: Tue Oct 02, 2001 3:01 am

westy second battery wiring question

Post by Derek May » Sat Feb 23, 2002 3:35 pm

More information:

My van is a '75, and the only thing the battery is connected to is the fridge, everything else in the Van is on the primary battery, including the florescent light. That's the factory Westy wiring for '75, not sure if its different in later years. I thought about wiring the stereo into the secondary circuit but haven't. may also be a good idea to put a cigarette style plug under the back seat, wired into the secondary circuit.

My fridge, on battery alone, drains down the secondary battery after about 8 hours of operation, and takes about 12 or more of driving time to recharge.

Can't recharge from the ac plug like you can, I've seen that later transformer and would like to replace the earlier and simply transformer in my '75 one day.

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Bob Ingman
Posts: 2869
Joined: Mon Mar 19, 2001 3:01 am

westy second battery wiring question

Post by Bob Ingman » Sat Feb 23, 2002 8:20 pm

Danny, you got Jakes new motor hooked up yet? Bet you`re going to love it. Better thank your brother big time.
About the double wiring diagram, just follow the steps above i gave to get on type2.com and its there for you. Good luck. Bob

papun5880pr
Posts: 245
Joined: Mon Oct 29, 2001 3:01 am

westy second battery wiring question

Post by papun5880pr » Mon Mar 04, 2002 11:26 pm

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Bob Ingman:
<B>Danny, you got Jakes new motor hooked up yet? Bet you`re going to love it. Better thank your brother big time.
About the double wiring diagram, just follow the steps above i gave to get on type2.com and its there for you. Good luck. Bob</B><HR></BLOCKQUOTE>

yes i did and i'm having the time of my life.i'm working on the secondary battery set up and will post the idea soon.i'm working with the possible ways to do it or update it to our satisfaction.hey,i'm just and electronic technical designer with nothing else to do.i get bore and go out and get a diploma.have 3 allready: computer programmer(1980),electronic designer(1997) and electrcian(high school job training).i love running those cables around.did i mention my vw bus was a gog house when i bought it for 2 years and the mice and rats made a mess with the cables.it tooh time and pain but i re-wired it all in a couiple of weeks and no fires,shorts or anything since them.

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