Running different batteries?

[wishbone]

Are caravan/leisure batteries more along the line of a typical SLA battery then? Charging finnickiness and all?

Hi Matt,

When searching for mine they seemed to come in several varieties.

The cheapest were pretty much the same as standard car batts, with the plastic plugs for topping up.

Then you had the sealed wet acid type.

Then various gel types.

The prices go up and up..... Lots of 'psuedo' gels / calcium / blah blah blah stuff.

I ended up going for a lucas sealed acid type as it was the best match for my budget and amp/hr requirements. Obviously there are better batts available but hopefully this will perform as it should for my application. (running a fridge overnight at campsites where no electric hook up is available)

It will be clamped to the boot floor, inside an ammo box with a pipe venting to outside.

What 'finnikiness' are you refering to re: charging?

Rob.

[wishbone]

What I intend to do before next year is run some 50amp cable to the boot, and install a split charge circuit in the cubbyhole that houses my rear fuse board. So when the first battery is flat I can just connect it to the car and it will charge whenever we go out for a drive.

Reading up on this stuff (there's not much online is there ? ) I found a split charge relay manufacturer recommend the wiring being capable of safely taking the alts whole current output. ~70amp on a surf. They reckoned a flat batt could draw loads of current for a short time before settling to a smaller draw. At least fit a fuse at each end lower than the cables safe amp rating.

Rob.

[MattF]

What 'finnikiness' are you refering to re: charging?

The narrow recharge voltage range before you risk frying them.

[wishbone]

Narrow meaning -blank-Volts to -blank-Volts...

Could you fill in the blanks ?

Rob.

Btw I did come across DC - DC chargers in my searches as 'they' reckon an alternator will never fully charge a leisure battery. (up to 70 - 80% was quoted)

[MattF]

Narrow meaning -blank-Volts to -blank-Volts...

Could you fill in the blanks ?

Rob.

Btw I did come across DC - DC chargers in my searches as 'they' reckon an alternator will never fully charge a leisure battery. (up to 70 - 80% was quoted)

My, you want specifics too? No pleasing some folks.

Just had a peek at the Yuasa which is sat here, and the range on those is 14.4V-14.8V. They're tardy buggers if you go above that, unlike vehicle batteries which'll accept a wider range before throwing a wobbler. Are the leisure batteries more akin to these or normal vehicle batteries, in that regard?

[wishbone]

Honestly Matt it's a minefield out there on battery info.. I recently emailed a major manufacturer about a certain leisure battery with all the info ... my vehicle, the charging voltage, the alts output, the amount of amp hours I wanted etc....

The answer was like something from the labour party.. we can but can't but look at these graphs but then but no but. maybe ........

I'll try and get some decent info tomorrow - it's a bit late now.

tbh I don't think many vehicle alts go above 14.4 V .....

I'm going to go outside right now and measure the surfs voltage at battery running...bear with me..


Rob.

[Maverick]

Reading up on this stuff (there's not much online is there ? ) I found a split charge relay manufacturer recommend the wiring being capable of safely taking the alts whole current output. ~70amp on a surf. They reckoned a flat batt could draw loads of current for a short time before settling to a smaller draw. At least fit a fuse at each end lower than the cables safe amp rating.

Rob.

The wire that was supplied (and recomended in the information) was 30amp (got used on a different job a couple of years back). So I estimate 50amp should be overkill. I thought that a surfs output was 100amp (or at least I thought I read it somewhere).

With regard to the fridges (when in Scotland we tend to run two as the local supermarket is a 4 hour round trip). We run ours on gas, the built in one just about maintains fridge temperature, whereas the portable 3 way I have to be carefull with as it likes to freeze the contents if I'm not carefull (turn to minimum before going to bed, because the drop in temperature effects it).

[Maverick]

I'll try and get some decent info tomorrow - it's a bit late now.

tbh I don't think many vehicle alts go above 14.4 V .....

I'm going to go outside right now and measure the surfs voltage at battery running...bear with me..


Rob.

What do you mean late, I'm just over halfway through my shift

Mine puts out 14.5v with the idle up activated (it will get there without the idle up, but takes longer to replanise the juice taken by starting).

[wishbone]

Ok mr awkward pants .........

It was 13.88 on idle on my old girl....

Bear with me while I go out again and get even wetter feet and soggy pyjama bottoms

Yes I know I should bother to put shoes on but...

Rob.

[MattF]

Honestly Matt it's a minefield out there on battery info..

Tell me about it.

I thought that a surfs output was 100amp (or at least I thought I read it somewhere).

Either 60A or 70A, if I remember correctly.

[Maverick]

Bear with me while I go out again and get even wetter feet and soggy pyjama bottoms
Rob.

You've got rain, I knew there was some benefit from working at a chemical site.

[wishbone]

Ok with even wetter feet and soggier PJ bottoms I can safely say my surf kicks out 13.88V with idle up, same as at idle.


I'll be putting in loads of new cabling soon so we'll see if that changes.

Rob.

[MattF]

Ok with even wetter feet and soggier PJ bottoms I can safely say my surf kicks out 13.88V with idle up, same as at idle.

I can just imagine what your neighbours must be saying by now. 'Oy love, that weirdo's dicking about with his 4x4 again, in his pyjamas no less'.

[wishbone]

You've got rain, I knew there was some benefit from working at a chemical site.

It's been lovely all day, I was working till 9.30pm and on the way home it started raining. I was planning a night out in the garden with a fire going but.....

Hopefully it's gonna be as good as they've promised tomorrow as I've got a rack of ribs defrosted, seasoned and ready for the bbq..

Cheers,
Rob.

[wishbone]

I can just imagine what your neighbours must be saying by now. 'Oy love, that weirdo's dicking about with his 4x4 again, in his pyjamas no less'.

Luckily I have no neighbours, I could have done that naked... Maybe for a different site - naked bloaters with voltmeters . com


When I lived in London I did walk up the offie in PJ bottoms, slippers and a t shirt sometimes so maybe it's not so bad ? !

Rob.