Leisure battery

corktina wrote: »

(I'm still assuming it's a relay....)

Most of the simple (four terminal) relays I've seen in vehicles have the same numbers on the terminals. 85, 86, 87, and 30. According to this diagram.



I only remember the sequence (3 in a row and one odd),. Google seems happy enough to verify the same numbers.

corktina wrote: »

here am de news....

tried another relay, couldn't hear or feel that click either (but then again I am officially deaf and my hearing aids might not pick it up)

You should be able to feel it working too if you put a finger on the back of it.

corktina wrote: »

so I re-did a couple of connections and now have a live signal wire running from the back of the Alternator as original....I'm going to assume that the relay is working and leave well alone. Now plugged into mains with fridge on....battery meter should stay the same , should it not if the charger is working

If you see the leisure battery voltage rise when the engine is running then it's working. Halfway there then.
Fused every live I hope and both batteries?

Fridge set to mains or 12v? It it's set to 12v the battery won't charge very quickly as the charger will just be powering the fridge really.
On mains charge the voltage should be slowly creeping up from 13.8v to 14.4v/14.7v depending on the charge algorithm as the battery get's topped up. Once it's charged it should drop to a consistent 13.2v/13.6v float voltage.
You'll find alternator charge is significantly more aggressive.
If the battery is weak then it may fluctuate between 12.8v and 13.2v/13.6v on mains float.

I find one of these quite handy for quick reading, they're not highly accurate (+/- 0.3v) but they're cheap and a bit more specific than what you're using at the moment.
If you wire a handy 12v cig. lighter port (with 5v USB port for phones) into the back you can read all the batteries separately and together; engine off dash port = starter battery voltage (if cigarette lighter socket is always on), engine on = linked batteries combined voltage, engine off living quarters port = leisure battery voltage.

corktina wrote: »

Thx for the help btw, much appreciated , clarifies the thoughts when you bounce them off someone else

No worries, I'm looking for any excuse to avoid this feckin' tin worm...hate painting I do.

It's a 7A fridge and a 15A charger.
Still though I'd advise letting the battery charge up and drop to float before turning on the fridge. If you load the battery that heavily while charging you'll fool the charger into thinking it's not taking charge. So the charge will be suspended at high current near 14v which will boil your battery and destroy it pretty quickly.
Is the battery getting hot/making bubbling noises?

If you've been running the fridge like this a long time it's likely you have gassed off a lot of the electrolyte.
Maybe it might need some topping up of the electrolyte with de-ionised water. There's usually level markers visible once you remove the cell caps (warning; danger acid and all that yadda yadda).

By the way your fridge manual say's it works on mains with the same element as 12v.

ha snap!...grand so...suppose this exhaust won't paint itself...

If you had the fridge off while charging yesterday and your leisure battery meter was showing >13v while on mains charge I can confidently say your leisure battery is dead and probably beyond salvation.

I hear you can get €0.50 per kilo for battery scrap in the right place but I have yet to confirm this myself.

If you are getting a new one I don't recommend any of the sealed ones as they're not designed to take what most alternators throw at them and they're non-serviceable.
I hear Numax/Exide are good value for money, and durable. Personally I'd rather 2 Trojan 6v in series or similar golf cart battery as these
can take some real abuse. If you want the best though it's gotta be forklift batteries.

For a long lasting leisure battery it ought to be a deep cycle semi-traction or mono-block, full traction (mega-bucks). I'd steer clear from AGM/gel types as they're too expensive and easy to destroy.
I'd see what your alternator kicks out accurately (it could be anything between 14.0v < 15.1v) and get a battery that can accept this, see the battery charge requirements on the manufacturers web-site. If the manufacturer doesn't specify bulk, absorption, float and rate of temperature compensation charge levels then I would disregard the company as unprofessional (that's just me though...most people aren't so picky).
It would be a good idea to compare this to the compatibility of your mains charger too. Ideally the max voltage for all charge stages ought to match the battery's acceptance limitation on all generators.

If you want to disregard all that then I hear Varta can cut some mustard too (only sealed versions as far as I've seen).
I can't vouch for Lucas but I get the sense these are good upper middle of the range.

Battery sites;
http://www.batterymegastore.co.uk/
http://www.alpha-batteries.co.uk/
http://www.tayna.co.uk/Leisure-Batteries-C45.html

You can of course choose a cheap and cheerful car starter battery but it won't last as long as a deep cycle as it's designed only for large cranking loads not consistent discharge.

When you are picking a new one it's best to estimate your Ah usage between charges and double it, as to keep a healthy battery you must maintain it above 50% (12.2v). Or >12.4v would be even better.
Depending on how you treat a wet cell battery you can get between 2 and 11 years service life.

Deadly I just got my 3rd star

corktina wrote: »

I then went for a 10 mile drive with the fridge on. Leisure battery went down immediately to about 11v, main battery at almost 13v. Checked fridge after 10 miles, warm still, no sign of life. Turned off fridge, leisure battery recovered to about 11.5 or 12v on way home.

Clearly the leisure battery, whilst it may well be weak and old (like me) charged from the mains but was not charging from the alternator, which is most odd.

I don't know how I missed this entire section of evidence earlier. But you figured it out so all good.

If you have two different readings from your two batteries then you know they aren't linked and vice versa. Say Battery #1 is 12.8v and Battery #2 is 12.4v then when you link them they will be 12.6v.