Which amp wire between charger and leisure battery

[timski]

Hi there,

Can anyone tell me which amp wire I need to use between the charger and the leisure battery? Also any advice where to buy the wire?

Sorry to whoever answered this one before for me. I can no longer find the thread in my threads so I guess it must have been deleted for some reason? Was a while ago.

Thanks,
Tim.

[CovKid]

40-50amp

http://wiki.club8090.co.uk/index.php/Ca ... it_charger" onclick="window.open(this.href);return false;

[California Dreamin]

Charger? as in 'mains' 230volts? then just double (over a short cable run) the rated output of the charger (on the 12 volt side) as a minimum....so 20 amp wire for a 10 amp charger. However, over longer cable runs treble this. Fuse rating (12 volt side) times rated output by 1.5, so 15amp fuse for a 10amp charger.

Of course don't skimp as is won't hurt to go heavier.

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

Martin

[CovKid]

Martin is correct - misread the question. It was late though.

[kennyjackett]

Hi, sorry to hijack the thread..
Im just about to change my relay set-up to 50 amp.. Ive an autopsleeper with leisure battery behind the passenger seat. The wires on there appear to go out through a hole and under the chassis to connect the two batteries. Is that right? How can I tell if its 50 amp wire in there already? Where do I put my multimeter?
Sorry, I am totally clueless on electrics! I have looked at the wiring diagram on the wiki and I think I get it

[California Dreamin]

There really isn't a way of testing the wires rating with a meter...you could accurately measure it's diameter which would give you a clue based on physical size (take a pici and we will guess)

Chances are if you are up-rating the relat TO 50 amps then the wire rating would have been much less (30 amps perhaps).

Martin

[baj25]

Why are you changing relay to 50A? If you leave fuses the same (assuming they are correctly rated in the first place) then no need to change anything else. Bri

[kennyjackett]

Well, just been having a few issue with the leisure battery not recharging..
There is currently a 35 amp in the fuse holder on the leisure battery side and a 30 amp on the starter battery side. That side was just taped up and has no holder just a fuse 'taped' into the brozne clips at end of wire.. I guess I could just get a holder for that side? Here are pics.. On the wiki it says 50amp wire..
(this is after I have taken tape off and just set up for pic..

[baj25]

OK, if you just replaced the relay, no need to worry about what size wire you have. I really would put a new fuse holder in, they are not expensive.
Do you think that changing the relay has solved the charging issue you originally had? Bri

[kennyjackett]

I haven't changed anything yet. I think the problem may have been the fuse from the starter battery as when I opened the tape it was in a bad way. I think Ill get a fuse holder and replace both fuses and see what gives. Would 30amps in both be about right?

[baj25]

30A is typical. Some go as high as 40A, depends on other parts in the system. Lower is safer. HTH, Bri

[California Dreamin]

OK....I notice that insulated 'Blue' crimp connectors have been used...the heaviest wire that these take is 3mm2 rated at 27.5 amps but will handle quite a bit more for short periods.

Don't panic...although this isn't really heavy enough it is unlikely to cause an issue. Single leisure battery circuits can initially draw 'mid 30's amps' (with a flat leisure battery) but drop down in seconds to low 20's.
Ideally that wiring needs up-rating to minimise voltage drop, however, if kept as is, ensure you continue with the 30 amps fuses to keep things safe.

Martin

[California Dreamin]

30A is typical. Some go as high as 40A, depends on other parts in the system. Lower is safer. HTH, Bri

Lower is safer?

Martin

[ghost123uk]

30A is typical. Some go as high as 40A, depends on other parts in the system. Lower is safer. HTH, Bri

Lower is safer?

Martin

I think Bri likely means fuse rating, not wire size.

That side was just taped up and has no holder just a fuse 'taped' into the bronze clips at end of wire..

Dear oh dear, I wonder who on earth did that bodge I mean, a proper blade fuse holder, with moulded in wire tails is only about £1.25 from any place that sells motor spares.

[California Dreamin]

Oh I see....

Fusing at 30amps seems to be the norm however, this does mean you could well blow this fuse on occasion.

40 amp fusing is going to be less problematic as long as all the associated wiring/relay/terminals, are rated higher (45amp wire/maxi fuse holders/50 amp+ relay/larger terminals etc) as the old saying goes...'only as strong as the weakest link' and the weakest link should always be the fuse.

Martin