Rear winch battery/alternator power setup opinions/tech

[pruggerdore]

Ok situation. hilux single cab. commy v6, 85amp alternator. winch behind cab, rope to back thru pulley block and back to front. works well. 2 batteries behind cab for winch and one in front for every thing else. I have this setup so alternator thru 15mm cable feeds back batteries first and then another cable carries transfer charge thru to front batt for charging that.
My thoughts being that putt the power to the winch batteries first to replace the heavy drain. My understanding has always been ( but may be wrong) that when one battery gets full, the first in the system it will shut down an alternator meaning the second battery will only get a transfer charge from the first battery. Is this correct ??? or will the alternator just charge all in the system evenly as one big "tank"
Not interested in a charge equalizer due to the expense. aim to setup 2 volt meters so I can see whats happening. offroad only so not concerned with battery abuse. just trying to make the winch get the best from the alternator. Think Im missing something so here I am. thoughts ??? .........

[sibainmud]

This is easy and rather inexpensive
I have similar setup in my truck.
Use a VSR (voltage sensitive relay)
The most important thing is make sure that the sense wire on the alt is hooked to the winch battery or the same place the output ends up.
With a VSR, when the 1st battery reaches 13.7 volts it connects both batteries together and then the alt can sense the second battery with all the constant load on it, like radios, lights, and all the systems need to run the truck.
I must admit I went the extra distance and changed the starter and glow plug loads to the big winch battery too.
If you want further info, just ask.

Hope this helps.
Cheers,

[pruggerdore]

cheers for that. anybody else out there with brain function or even a muppet with an opinion

[wjw]

This is easy and rather inexpensive
I have similar setup in my truck.
Use a VSR (voltage sensitive relay)
The most important thing is make sure that the sense wire on the alt is hooked to the winch battery or the same place the output ends up.
With a VSR, when the 1st battery reaches 13.7 volts it connects both batteries together and then the alt can sense the second battery with all the constant load on it, like radios, lights, and all the systems need to run the truck.
I must admit I went the extra distance and changed the starter and glow plug loads to the big winch battery too.
If you want further info, just ask.

Hope this helps.
Cheers,

What he said

[wjw]

http://www.smartmarine.co.nz/710125avsr ... -5336.html

You need to get one big enough to cope with the draw you winch will need at stall. This one is 125Amp.

[pruggerdore]

dosnt answer my original questions tho on the alternator being shut down by the first battery or will it just see the second battery as the same battery and carry on pumping.

a vsr to match size of alternator not winch wouldnt it be as our winchs draw hundreds of amps.
also the second battery in the front to run a few lights etc would not need a huge power supply and a simple small transfer charge from one battery to the front would suffice. there still in the same system so are linked as only one alternator so have to be. only difference is alternator feeding winch batt first. so want to know if the first battery in the system will shut alternator down or not or will it just keep going until there all full. a vsr will sort it yes but I dont think it is necessary as long as cables between batteries are heavy enough to carry starter motor current without a melt down

[pruggerdore]

trying to increase my knowledge. been reading what they say on the vsr in the above link and got me thinking. they say you need one to isolate the batterys in a boat/motor home situation dual battery setup. so as to separate the 2 systems so you don't flatten starting battery's when the alternator isnt running from the house side of things. Or you could simply put a relay in that only activates from the alternator so is automatically disconnecting batterys when the alternator is stopped. how do i know this works. our professionaly wired motor home is done this way and works fine. think this propably means an alternator will see all battery as one tank and charge all at once. so by having alternator feeding winch first will simply mean it is getting the best possible alternator supply.
tell me Im wrong and why

[De-Ranged]

....tell me Im wrong and why

oh so tempting

Got a book for you here.... its the auto electrics one I was reading awhile ago, from what I've skimmed out of it your "one big tank" thoery is right.... but this isn't something I'm gona stick my neck out on take it home

Cheers Reece

[NJV6]

VSR is good for knowing you want to be able to start the vehicle again after a long winch as one battery is still fine and it will charge accordingly.

However the best for winch power is to connect the two batteries so it drains them both. Low voltage kills winch motors through more heat (as volts go down, amps go up). The VSR cuts out the 2nd battery when power gets below 13v (or whatever it is) just when you want it to give more power!

I have been running two batteries joined with a 50mm cable and an alternator wire to them both for a few years with no trouble.

[wjw]

I actually ended up using a VSR and one of these:



http://www.smartmarine.co.nz/721-contou ... p-590.html

Gave me the best of both worlds:

1. Both batteries permanently connected with alternator
2. One battery to alternator other one on VSR

Most of the time it would be on 2 so that if I left the stereo running, boys left interior lights on etc it would start. But when I knew I would be doing lots of winching I could flick a switch and get both batteries.

You could do it with a 2 position one, but I wanted to be able to isolate the two batteries, so I could take one out.

[darinz]

If it is off road only then just do what you are talking about and when you get home charge the batteries with a charger individually.
I know a few offroad only trucks that do this and it works very well.
If you are going to be doing comps or road use then fit VSR (or similar)as said above.
Also when you say 15mm cable I assume you mean diameter as cable is rated in square mm normall and I use 16mm for my alternator? Even 50mm is boarderline being big enough and I'd suggest 70mm is the minimum for a winch.

(Did you sort the auto issues?)