Leisure battery chalenges

[el_presidente]

Evening all

I have read a lot of wikis and other posts on leisure batteries and split charge relays but if I can be indulged I'd like to set out my symptoms...

Camping with no hookup in a field my leisure battery was basically dead within a few hours of setting up, having attempted to run a fridge and a water pump.

I had no multimeter or tools with me and only there for one night so just ignored it and came home yesterday,

Went to check it tonight and realised I had left the fridge switched on. Leisure battery is completely drained (0.08V). When I start the engine the split charge relay just clicks and clicks.

My starter battery is 12.5V cold and alternator is kicking out 13.0V at idle. Seems a little on the low side but OK - I never have any issues starting the van.

I might try replacing the relay first as that is a bit cheaper than a new battery. Anything else I should be checking - gave the wiring a once over and couldn't see any obvious bad earths etc.

thanks

[Oldiebut goodie]

You can't run a fridge from a battery - it will drain it in 2 - 3 hours. You should be running it on gas not 12v.
You have most probably killed the leisure battery running it that low! The engine will never charge a battery that dead - that is why the relay is going haywire. (The relay isn't at fault)

[CovKid]

Spot on advice. At the weekend I came across a leisure battery in a friends camper that only displayed 8 volts. We just ditched it and fitted a new one. Its toast once its been flattened. Ghost123UK recommends a circuit that stops you draining the battery below say 11.75 volts to protect it but I think in this instance you need to fully understand what the leisure can supply. 12v fidges, stereos and some TV equipment are right out - ok on hookup but otherwise far too much draw.

All mine does is the important stuff - lights but predominantly power for the spark in my Propex heater so we're warm at night. Everything else should be either portable battery powered stuff or be drawing just a few milliamps. Solar is OK and so is an extra battery as backup but you still need to watch what you hook up to a leisure.

[slowcoach]

Unless you're lucky enough to have a 12v compressor fridge ours is 30 years old and hums along nicely

[el_presidente]

Very interesting, many thanks.

So my 3-way fridge (240v, gas, 12v) should be used 240v when on hookup, 12v when driving, otherwise gas?

Many thanks, Ian

[California Dreamin]

Indeed...it draws something like 8 amps continuous so will drop to damaging levels in 4 hours (80ah battery fully charged)
12 volts is fine when driving but you always run the risk of 'forgetting' its on 12 volts when parked up at services etc.
Some fridges are wired on a separate 'split charge' circuit, so will only receive 12 volts when the engine is running (this is the best idea).
See on the diagrams:
Terminal C3 (4) which is a separate supply for the fridge 'as well as' a 'traditional' split charge relay.

http://www.autoelectricsupplies.co.uk/p ... tegory/149" onclick="window.open(this.href);return false;

Martin

[el_presidente]

Every day is a school day... thanks all

[bigherb]

Went to check it tonight and realised I had left the fridge switched on. Leisure battery is completely drained (0.08V). When I start the engine the split charge relay just clicks and clicks.

My starter battery is 12.5V cold and alternator is kicking out 13.0V at idle. Seems a little on the low side but OK - I never have any issues starting the van.

I might try replacing the relay first as that is a bit cheaper than a new battery. Anything else I should be checking - gave the wiring a once over and couldn't see any obvious bad earths etc.

thanks

What type of split charge relay is it? If it is voltage sensing then if there is a high load (charging a flat battery) it may be pulling the voltage too low and the relay switching off until the voltage rises switches on again and just repeats that cycle.

[el_presidente]

Well I just checked it and the solar panel had charged the leisure battery back up to 12.33v .... not bad


I still think I will get a new battery as I won't trust that one any more.

[greasemonkey]

A dead battery will still show 12v no problem. The voltage isn't a test of condition, its how well it holds that voltage under load that matters.

If it's dead you'll find it drops from 12v very quickly once a load is placed on it.

[el_presidente]

Understood

On my previous T25 I had a starter battery fail under similar circumstances.... it's all coming back to me now

[tonymoss328]

Well I had a similar problem no electric hook up so using what I thought was the leisure battery left the fridge running . My van battery was dead this morning but bump started and has been ok and my leisure battery has leaked acid all over the floor , do you think I need a new battery or could it be something else

[Synkraut]

I'd advise installing a battry guard that terminates the power supply as soon as a cerain voltage threshold is reached. Good ones are not cheap but they cost less than a new leisure battery does

[CovKid]

These are fine though at £15 and are rated at 20 amps so could go before leisure fusebox. That would do it. Or you could bypass one thing like the lights (for emergency purposes) but leave everything else fed via the battery guard. It won't go flat then.

http://www.ebay.co.uk/itm/BATTERY-GUARD ... 20daaf2342" onclick="window.open(this.href);return false;

[Oldiebut goodie]

Don't forget that you can use the lvd to switch a big relay if you want more amps to flow.