Battery charging/fridge operation

888dee

Guest
or not as the case maybe...

as I have investigated further I've decided to start my own thread rather than hi-jack another ;)

'92 Frankia A730RD on Peugeot J5 chassis fitted with one of these...

IMG_7750.jpg


engine off, front battery 12.7v, rear 12.6v
engine running front battery 14.4v, rear 12.6v, doesn't seem to matter what I do with the panel no increase in voltage on the rear battery to suggest charging

been suggested there might be a problem with the split charge relay but haven't been able to find one (traced the +ve from the battery right back to the panel and there is no relay) also the connection to the panel is live when the engine isn't running...

even at this age ('92) is it possible the split charge relay is built into the panel?
 
oh and I've managed to find contact details for the german manufacturer of the panel & asked for a wiring/installation diagram so fingers crossed, unless anyone has one for this or a similar panel???
 
You were checking the wiring from the starter battery/alternator for the split charge relay and not the leisure battery wiring? Not trying to teach you to suck eggs but it isn't too clear which you have checked.
 
what I've found so far

and the rear, top row of screw downs is the negative buzz bar, bottom row, left to right,

1- Fridge 12v +ve,
3- pump 12v +ve,
4- Lights 12v +ve,
5- dunno,
6- negative from the front battery,
7- nothing,
8- dunno,
9- constant +ve of the rear battery,
10- constant +ve of the front battery

extreme right is the 240 in.

when the engine is running 14.2v is present on terminal 10 but there is no increase on any of the other outputs to suggest the split relay is allowing the output from the alternator through, now whilst I understand some unit's don't allow the full alternator output through to charge the leisure battery I would expect some increase in voltage, even a small one and given me multimeter goes to 2 decimal places.....

can't get the fridge to fire up on the 12v at all :(
 
There will likely be a control wire coming from the ignition circuit to tell the control system that the ignition key is turned on (and presumably the engine is running) This can come from say, the brake light circuit, an oil pressure switch or dirct from the ignition switch. Will only be a thin wire since it is not supplying heavy current. It is also used to switch off habitation lights, retract the step and satellite dish if these features are fitted.

Might be one of your 'dunno' terminals

Not all systems have this and others just monitor the engine battery voltage and switch once the engine battery is higher than around 13.8 volts
 
If there is no heavy duty battery cable for you to trace to your relay you may not have any split charge system which seems unlikely. You will have to trace to your alternator or starter battery rather than the control board to find your relay if there is no heavy duty cable present in the panel - it will be quite thick as the control panel is showing a possible 50A load - then check the wiring for switching the relay. I would have thought that you would soon notice the hefty cable and relay if it were inside the control panel.
I would suggest find the relay before you start in the control panel - then you will at least know what colour the wire is that switches the relay and trace that if the relay is not working.
You should not get the fridge to work on 12v until the relay has operated, wherever it is hiding.View attachment 564
 
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sorry, meant to post this aswell, my identification of the terminals will likely make more sense now.

P1030972.jpg
 
The two heavy red wires are only the battery feeds- vehicle and leisure. You need to find the heavier wiring from vehicle battery/alternator to leisure battery to find the relay.It should be almost starter motor cable sized.
 
I'm not familiar with this control box but I would expect this unit to have it's charge control relay fitted internally.

Terminal 10 will likely be the charging feed from the starter battery, inside the box there will most likely be a a relay linking terminal 10 with terminal 9, to charge the leisure battery.

This relay may operated by a feed from the alternator, most likely one of the thin wires, you can check for this by using your meter to test for a wire that shows around 14v ONLY when the engine is running, it should be at 0v with the engine stopped and ignition off. If you find a wire like this then you can be pretty sure that the fault lies inside the control box.

If you don't find a wire like this then there are two possibilities:
1) The unit has a voltage sensitive relay
2) The wire is there, but is a fault in the connection to the alternator.

Some of these control units can be be quite sophisticated, with voltage sensitive circuits operating charging and fridge relays, you may find that you need to get a competent motorhome electrician to check it out.

AndyC
 
and here we have it, the root of all evil!!! the scotch lock :mad:

found a smashed fuse holder hiding in the back of the engine bay, replaced that, traced down that wire to find the alternator control, checked it, enter one sh!tty scotch lock, replaced that and bob's yer aunty and all that....


Happy bunny is me, especially cos I was able to find it myself (with you guys to help :) ) cost a total of £1.25 to fix, happy days....
 
scotch lock

Well done that man
the number of times scotch locks are the probem
is hard to believe .

is there any other safer/easy way to add a junction to a wire?

weez
Tony
 
Wee-z said:
Well done that man
the number of times scotch locks are the probem
is hard to believe .

is there any other safer/easy way to add a junction to a wire?

weez
Tony
Click to expand...

I solder every connection I make, it may be time consuming but it never fails nor does it create a point of high resistance.

Why are those ridiculous items even on the market?
 
My turn now but I'll sit on my hands and do a little more reading and checking before I start sharing.

I have the same German manufactured (Electroblock) control panel but a different model, I traced 12 V into and out of the relay which is in the Electroblock so it appears I'm getting 12 V to the fridge.

Next stop is to test the 12V element and then, maybe, just maybe, the LED is bust and the 12V element is working or maybe there's a scotch-lock in there causing trouble. Problem is, 12V elements don't seem to do much so it take time.

I used gas along the roads when I went to Ireland recently, Ok, I don't have a cut-off valve type regulator but I do have all steel and stainless-steel pipes and hoses.

Richard.
 
I did a little more searching, found 12V at the fridge when the engine was fired-up but couldn't get to the 12V element without taking-out the whole fridge which is a mammoth task.

12V negative appeared to go to the thermostat switch which is a trick some washing manufacturers use, I think to stop sparking and the live seemed to disappear into the switch panel but I couldn't get it off without taking the fridge out.

Did a continuity test but that was inconclusive because I couldn't isolate the 12V feed. B--------s,why do they make stuff so difficult to maintain.

If I could get a Dometic engineer like the one I found in Scotland last year I'd happily pay for the help. This bloke knew what was wrong with my fridge before I turned-up, he had an ignitor unit in his hand as we rolled-up and fitted it in minutes.

I'm a chance-er, I don't want to pay someone who is an expert-chance-er.

These motorhome appliances are really crap, I don't remember ever having a fridge go wrong, even my box fridge that I used for tent-camping which is a three-way also never produced any problems and I'm reading lots of fridge problems on the forums. Mostly 12V.

The 12V element is so ineffective compared to gas I would rather use gas when I'm traveling. In-fact, unless one of you come-up with an idea I think I'll bin the idea of repairing whatever is wrong.

Richard.
 
I have wondered about using gas whilst travelling because as you say the 12v is really not effective, ours struggles to maintain temperature but is it not technically illegal to use gas on the move?
 
In the UK it-is technically illegal for all-sorts of things that have become acceptable on motorhomes, hobs without cutout valves on the glass hinges and lack-of or poor ventilation to water/space-heaters.

I doubt you are breaking the law by traveling with gas on and working, the problem you have to face is what happens in an impact situation ? A vehicle fueled with petrol will go-up like a bomb.

My view is that whilst you have flame-failure device on your heater or fridge and sound hoses, stainless-steel hoses are even better, then the risk assessment is about the same as a petrol fueled car. You can, of-course buy a regulator that cuts the gas if full-flow occurs, these have been on the market for plumbers for 25 years for those who chose to pay the extra, I never saw anyone using one but I have one.

What about a car/van that is fueled by LPG, they don't travel with the gas-off and I bet not many have regulators that cut the gas if full-flow occurs.

You need to be sensible, cut the gas at filling stations in much the same way as you wouldn't smoke.

If I had room in my locker for a valve that cuts the flow if full-flow occurs then I'd fit one.
 
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