# Battery Problems



## 97943 (Mar 2, 2006)

Hi All,

having a bit of a battery problem, probably best if I explain whats happening and pointing out that 12v power systems are not my strong point  

RV has 4 x 70ah leisure batteries. 
Just got it from the dealer and had the RV parked for a few nights and used very little power (the odd minute or 2 of water pump, occasional light, occasional double slide out) No Tv, microwave or any other juicy device. Ran the engine occasionally for about half an hour to replace some charge. That was Thursday through to Sunday. Never went to the RV from Sat afternoon through to when we moved it on Monday and the leisure batts were down to about 3v (the control panel in the RV was only barely reading the leisure batt, and the contol panel lights were all dimmed. 
The RV has a 2000w inverter which has an on/off switch on the inverter itself and an on/off remote switch in the bedroom. I have spoken to a couple of people about that and one said that the problem was that the inverter was switched on in the locker, and the other said that shouldnt have drained 4x 70ah batteries if there was no appliances getting used. I have now taken to turing off the house batteries from an on/off switch in the locker beside the batteries when I leave it for any length of time. I know that there are things on board that will constantly take charge from the batteries (gas alarms etc). I have the fridge switched off at the moment. 
I am concerned that either 

a) The batteries are knackered
b) the inverter is wrongly wired
c) something is drawing a lot of constant power that I dont know about (enough to drain them)

Any ideas?
Thanks for any help.

Cheers
J


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## DABurleigh (May 9, 2005)

Yes. Get some charge into the batteries then get a multimeter to measure the current drain from the leisure batteries with everything supposedly switched off. Switch on the inverter with no load and measure the drain then. 

Dave


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## Scotjimland (May 23, 2005)

Hi 
I had a very similar problem and symptoms when I bought our RV, the batteries were knackered .. you could have a drain but it sounds very much like duff batteries. I replaced with four 85ah cheapo flooded lead acid, about 30 quid each. 
I think that many RVing types rarely use batteries and don't bother looking after them depending on EHU most of the time.


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## 97943 (Mar 2, 2006)

I knew you guys would come back woth something  

Next question, how/where do I measure the current with a multimeter?  

Sorry


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## 96088 (Aug 22, 2005)

Check this for easy to understand multimeter stuff.

http://www.doctronics.co.uk/meter.htm

Meanwhile you are in good hands with the members that have replied to you. They will find your fault :wink:


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## Scotjimland (May 23, 2005)

Hi 

Excellent link from Oldskool.. thanks 

To measure if there is a current drain do this. 

Switch off EVERYTHING that may use 12volt. 
Disconnect the earth strap from the leisure battery bank, at this point if you see a small spark you know you have a drain. 
Select Amps on the meter and connect one probe of the multimeter to the earth strap, the other to the battery pole, polarity won't matter. 
Take as reading, it should be zero of course, get back to us if there is a significant current.


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## 97943 (Mar 2, 2006)

Cheers for the answer Jim, 

is that any pole on any of the lesuire batteries, or should I do it to each battery?


J


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## Scotjimland (May 23, 2005)

Hi

The batteries are connected in parallel and work as a 'bank' so you could in theory measure at any battery pole by disconnecting and putting the meter in series.. no need to do it at more than one point as it would be the same reading. 
I suggested the earth strap as it's usually the easiest to get at and identify but it doesn't matter.

Be aware that multimeters have three sockets for the probes, 
1.common, 
2.Volts/ohms and 
3.Amps 

Please make sure you select the Common and the Amps socket. before taking a reading.. 

Thanks to Ken S for reminding me.

Edited ..
parallel not series, thanks Dave, I'm losing the plot :lol:


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## DABurleigh (May 9, 2005)

I'm no RV expert but would they be in series with 4 * 70Ah batteries? Lead acids are 2 volts per cell so with 4 batteries I'd guess they would either be 4 12V in parallel, or 2 paralleled (2 in series * 6V).

Dave


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## Scotjimland (May 23, 2005)

DABurleigh said:


> I'm no RV expert but would they be in series with 4 * 70Ah batteries? Lead acids are 2 volts per cell so with 4 batteries I'd guess they would either be 4 12V in parallel, or 2 paralleled (2 in series * 6V).
> 
> Dave


ohh dear a senior moment  they are in parallel.. thanks Dave..


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## 88966 (May 11, 2005)

Hi,

All good stuff coming out as usual.

I always reckon a hydrometer is a good piece of kit (and cheap) for checking suspect batteries. Before and then after giving them a good charge check all the cells. They should be all at a similar level of SG.


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## G2EWS (May 1, 2006)

Hi Felixcor,

I guess the most important thing is, do you have a multimeter? If not where is your location and are you near one of us who has?

All advice given is perfect the only additional item would be to check levels in the batteries. They will run dry on charge and should be regularly topped up.

Good advice would also be to keep them on permanent charge if you have the ability. ie is the MH near to the house or somewhere you can keep it plugged in.

Chris


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## DABurleigh (May 9, 2005)

I'm sure this was pointed out recently but can't find it; as from tomorrow, Lidl have multimeters on offer for £2.99.

http://www.lidl.co.uk/uk/home.nsf/pages/c.o.20060626.p.Digital_Multimeter_or_Mains_Adaptor_.ar2

Dave


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## 97943 (Mar 2, 2006)

thanks for the answers guys, Im going to get an auto electrician to have a look at it and see if there is anything up. I'm no expert with batteries and dont want to start taking them out the locker as the wiring seems pretty complicated. The batteries are about 4 years old, not too sure how much use they,ve had. Not too sure how much experience this guy has with motorhome/rv systems though. Ill let you know what happens.

Cheers
J


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## gaspode (May 9, 2005)

If the batteries are 4 years old then just renew them. Lead acid batteries, even with regular use, will be well past their best after 4 years - and if they've been fully discharged through lack of regular use they'll be completely b******d :!: 

Like Jim said, you should be able to pick them up for about £30 each - we got our last ones from one of the shows at £45 for a pair of 85ah lead acids.


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## 96088 (Aug 22, 2005)

Felixcor said:


> thanks for the answers guys, Im going to get an auto electrician to have a look at it and see if there is anything up. I'm no expert with batteries and dont want to start taking them out the locker as the wiring seems pretty complicated. The batteries are about 4 years old, not too sure how much use they,ve had. Not too sure how much experience this guy has with motorhome/rv systems though. Ill let you know what happens.
> Cheers
> J


As someone who a year ago knew pretty much zilch about electrics; but now know a few basics thanks to this site, I would strongly recommend that you still get yourself a multimeter and learn how to use it.

They really are easy with a bit of thought 

Start with measuring the voltage across the battery terminals with the charger off, measure it again with the engine switched on or EHO connected. Disconnect the whole lot and measure it again after an hour.

Do the above for a bit of fun on a quiet day when you are bored and see what you learn :wink:

Then learn how to check your fuses without replacing them

Find out how your electrics work at a basic level and you will save yourself a loads of cash in the future :wink:

The above is from personal experience and I am now a person with 'a little bit of knowledge' which apparently is a dangerous thing 8O

I now know how to detect which bit of the electrickery I have blown up almost immediately :roll:

*Health Warning. If you really are not comfortable with the technology then ultimately leaving it to an expert who you can sue is probably a better course of action.*


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## 97943 (Mar 2, 2006)

yep, Ive been out with the RV manual and am now looking at getting the RV Electrics book from the arvm site. I had a look into the battery locker and instantly knew I was out of my depth. Hopefully it is a simple case of the batteries being knackered and a simple replacement will do the job, if not .. ......... 8O 8O £££'s 8O


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## DABurleigh (May 9, 2005)

That's why I never advise replacing the batteries first, even if this IS the most likely solution. For if you have a significant constant drain, you'll end up buying yet MORE batteries, real soon 

Dave


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## 97943 (Mar 2, 2006)

Just back from the RV and want to report my very basic findings:

Checked the Batteries on the RV control panel (sorry, just wasn't up to multimemter thing yet) heres the story (no loads on, no other lights, fridges, heating etc Had to keep one light on for the alarm guy, but it was on all the time):

9am - 11am (Inverter switched on in locker)
9am Reading : 11.70v
11am Reading: 11.46v

11am-12noon (Inverter off in locker)
11am Reading : 11.46v
12noon Reading : 11.40v

12noon -1pm (Inverter off in locker)
12noon reading : 11.40v
1pm Reading : 11.32v

1pm - 2pm (Inverter On in locker)
1pm Reading : 11.32v
2pm Reading : 11.14v

Is this kind of reading normal???

Cheers
J


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## DABurleigh (May 9, 2005)

No 

Did you try charging the batteries first?

I think we established already you have a problem, but we have to find out whether it is:

1) Due to a continuous drain, possibly due to a fault or something inadvertently left on (we've all been there ...), OR:
2) Your charger is not working properly, OR;
3) Your batteries are knackered.

1) or 2) can lead to 3), but just solving 3) by buying new ones won't solve either 1) or 2) if either exist.

Dave


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## G2EWS (May 1, 2006)

Hi J,

I refer you back to my previous message. Let us know where you are and one of us with a little more experience on electrics will be able to help and hopefully teach.

Let us have a town and anyone who is near can pm you to discuss further. Oops I am speaking for others, but somehow I think they will agree! Hope so anyway!

I hope you bought the multimeter from Lidls at that price it will be worth having one anyway.

Chris


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## 97943 (Mar 2, 2006)

Its like having a secret gang! Im in Glasgow guys, dont think there are 2 many RV ers up here! Just a quick jaunt up the M6 though! 
I went round all the lights and appliances to make sure all were switched off. 
I didnt charge the battery in the morning pre starting taking the readings as I figured a rested battery would give a better reading. I did charge the batts a bit before I had to leave and got them up to about 12.10v. around 6pm tonight. Itll be interesting to see what charge is in them in the morning. Im going to charge them again tomorrow to try and get them up to about the 12.40/5v region and then rest them and try taking the readings again. 
The worrying thing is I had a faulty alarm (ive posted seperately on it) and now think the 2 may be connected somehow, the alarm was fixed today, but after the guy went I discovered the alarm didnt work when I switched the house batteries off. I thought that was a bit wierd....

The multi meter is now definately on my shopping list


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## G2EWS (May 1, 2006)

Hi J,

Goddamn, just a bit too far from Wiltshire, I was going to suggest you pop into my office and workshop but not sure you want to travel that far!!

Right, back to basics:

1. The power needs to be on to the unit all the time. This is a good thing for a leisure battery. This means they will always have a good charge.

2. You will most certainly need the multimeter and as has already been suggested, with the charger off, disconnect one of the leads. Put the MM on to DC amps and the highest setting available. (I will try and buy one of the MM's tomorrow to see what the settings are). You will have a reading which you can now turn the setting down as low as it will go without overloading the MM. This should be in the mA reading and very low at that. Advise us once you have looked.

3. On the RV power panel there will be a row of fuses in the DC part of the circuit. You will need to remove all of these remembering which ones go where!

4. Check the ampage drawing now as in 2 above. This should read 0.

5. Put the fuses in one a time and check as in 2 above. Each time remove the fuse then put the next one in. You are then likely to find one of the circuits has a high current drain.

Advise us which one and between us we can then help to track down the fault further.

Chris


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## G2EWS (May 1, 2006)

Hi J,

Well I popped into Aldi yesterday to purchase one of the multi meters and they are not for sale. It seems there was a problem with them so they where withdrawn.

Maplin is a good source and this meter will do everything you ask of it:

http://www.maplin.co.uk/Module.aspx?ModuleNo=44679&criteria=Digital Multimeters&doy=29m6

And at £4.99 it wont break the bank!

Chris


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## 97943 (Mar 2, 2006)

Cheers Chris,

picked one of these up and fiddled around with it, all I need now is to build up a formative knowledge of 12v electrics, battery mechanics and multimeter use  8O   

The first auto electrician guy I had didnt have a clue, he fixed the alarm and when I mentioned for him to have a look at the batteries, he mumbled something and sped off in his van. Tried another guy today and he sounds more interested so Ill see what happens tomorrow when I take the RV to him.
Should be fun, commence chin rubbing, sharp intake of breath (I think they teach this in college) and pound signs flashing all over the place   
J


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## G2EWS (May 1, 2006)

Hi J,

It will be worth your while going over the notes I have put above. You should fairly easily be able to track down where the fault lies by removing all the fuses then putting them in one by one. As mentioned, with all DC fuses out there should be no current when you put the multimeter in line with one of the terminals of the multimeter. Basically disconnect the battery and put one lead of the multimeter on the battery post and the other onto the cable you have just taken off. It does not matter if the multimeter is connected the wrong way round it will just show a negative reading. Just make sure you start on the highest DC amp range, probably 10 amp. However, fear not you will only be drawing a small amount anyway.

Once you have the DC fuse isolated to where the current drain is ie the hopefully only fuse that is drawing a large current you will then able to identify exactly what it does. From this you can then look at the respective item. I am guessing of course but it may be an alarm system that has been badly installed (there are a few of these mentioned lately) or possibly a tv aerial amplifier that would be better turned off when not in use. Or of course one of a hundred different items!

Chris


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## 88966 (May 11, 2005)

Hi J,

I have just been re-reading this topic and everything that Chris is saying is good.

But, I have seen nothing yet that tells me you have successfully recharged the batteries ! I would want to see them up and reading over 12.6v after standing for a while. I also re-iterate that checking the SG of all cells will tell you a lot about the condition of the batteries. 1 duff cell in 1 battery if they are paralleled could give you a similar effect.


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## G2EWS (May 1, 2006)

Hi J,

Bill is correct you will need to check the specific gravity of the batteries. If my memory serves me correctly Halfords will do this for you foc. But check first, don't tell them it is an RV because they may not have the correct batteries and that will be your excuse to exit without paying for new ones!

Chris


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## 97943 (Mar 2, 2006)

gents, thanks again for keeping this post going, Its really heartening to read some great advice as there is no-one up here (Glasgow) that specialises in RV maintenance. I am taking the RV in tomorrow to a place where they are going to fit a 12v feed for my new macerator, so Im going to try and get them to check out the connections/fuses/batteries as well. If not I'll try and drop in somewhere on the way to France to get it checked. I know that Im out my depth here, but am learning all the time just by reading all your posts (old and new) eventually, I'll get some knowledge of the electrics, but because its me and the good lady in the RV, I dont want to take the risk of doing something really stupid myself and burning the thing down (preferably not with us in it!)

P.S. - The alarm I got fixed was wired onto the leisure batts (now wired to the engine batt), so that is possibly something to do with it. BillD, correct, I dont have a full charge in the batts yet, just not had the time to spend down there, keep getting called away!, When I left last night the panel read 12.09v and when I got there this morning it read 11.79v. but I'll get the genny going and try and get full charge into the leisure batts. How long should this take?
P.P.S - After reading the manual I beleive they are 4 x 6v x 70ah Batts, there is nothing on the batteries themselves that says what they are.

Thanks again guys
J


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## steveutwg (Jun 19, 2006)

Hello One and All

I am amazed at the levels of expertise within the members well done chaps!!! Wiggling a few wires is a job I do every day and yes your right to sling out the batteries but beware when they are on charge they give off hydrogen gas nasty stuff and in a confined space somewhat lethal so the old cheapo lead acid battery at £35 is fine if the area is well ventilated and the fumes don't come up through the floor, otherwise be safe and get the right batteries with a case breather so the fumes escape safely. 

If you want a proper test and you can get to our service centre in Eltham London I will test it for you with pleasure I will even throw in a cup of tea... 

P.S. I like the comment on the Hydrometeor I hear someone saying what the hell is that should of paid attention at school lads!

Thanks and good luck steveutwg


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## 97943 (Mar 2, 2006)

Thanks for the offer Steve, Ive got a mate in Peckham who's looking for me to drop some stuff to him on the way to France so maybe......
I'll see what the guy tomorrow reckons, knackered batteries would be a blessing the way I see it at the moment, pop in some new ones and away we go, dont want to contemplate anything else at the moment.
Just having a trawl on the old net and came up with these guys as a supplier
http://www.independentliving.co.uk/squadron/batteries.html
http://www.squadronbattery.com/

Particularly liked the MonBat range - If its good enough for NATO, it'll do me  

Cheers
J


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