How do I test leisure battery's (1 Viewer)

Feb 24, 2013
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not long enough
Evening Bill

There is an expression called a drop test

There is also pretty much an inevitable answer

If you think they are duff they probably are

Dropping them from about 15' will not prove anything, but you will certainly the need some new ones

probably not helpful, but line 4 possibly answers the question

(y)
 
Sep 10, 2013
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Put a multi meter across the terminals and measure the voltage after a period say half an hour of non use. Below about 11.9 volts and your in trouble. Google 12 volt battery condition for full charts.

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Wildbill
Nov 18, 2011
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Thanks done that today you have confirmed my findings
12.9 at 2pm at 6pm 12.8 on one and 12.7 on no 2 so I think ther in good condition
Willdbill
 
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Wildbill
Nov 18, 2011
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The reason I asked is I am fitting new soler panel when I get in from work tomorow
If time permits I am nights out rest of the week
Bill
 
Last edited:
May 8, 2016
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How I have done it in the past is to put a multimeter on them, measure the voltage, turn a few high load items to drain them over 30 minutes, keeping an eye on volt drop, then turn everything off and watch how voltage recovers. If it doesn't, then you may have a problem, if it does, then you are probably ok

Not the most scientific test, but at least it is testing under load conditions and checking cell recovery.

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Last edited:
Feb 24, 2013
12,997
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Bolsover, Derbyshire
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not long enough
Technically Bill you should get the same voltage reading on both batteries unless you have disconnected them, that is one problem with multi batteries, one dies they all appear to (y)
 
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Wildbill
Nov 18, 2011
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Technically Bill you should get the same voltage reading on both batteries unless you have disconnected them, that is one problem with multi batteries, one dies they all appear to (y)
So one volt drop is not a problem over 6 hrs I have just checked them five min ago and no Chang
Bill
Edit that are both disconnect from each other and the van

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May 8, 2016
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Bill, the voltage test under zero load conditions is not a definitive test. It is indicative only. Testing batteries under zero load doesn't give you the full picture

The best bet is to try to put a load on each battery in turn, say internal lights or better still a 12v kettle, test before and after, and see how voltage drops immediately the water has boiled, then watch to see each battery recover a little. If they recover at least a bit within (say) 5 minutes, then that tells you the battery is functioning well. If not, then perhaps worth speaking with a friendly garage to test them on one of their dedicated load testers

Edit: Halfords offer a cheap tester from Ring for around £14 - last you a lifetime. It puts the battery under a small load (350 ohms), so it gives a better indication of battery condition than a standard multimeter without knackering your battery in the process.
 
Last edited:
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Wildbill
Nov 18, 2011
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Over 25 year's
Bill, the voltage test under zero load conditions is not a definitive test. It is indicative only. Testing batteries under zero load doesn't give you the full picture

The best bet is to try to put a load on each battery in turn, say internal lights or better still a 12v kettle, test before and after, and see how voltage drops immediately the water has boiled, then watch to see each battery recover a little. If they recover at least a bit within (say) 5 minutes, then that tells you the battery is functioning well. If not, then perhaps worth speaking with a friendly garage to test them on one of their dedicated load testers

Edit: Halfords offer a cheap tester for around £14 - last you a lifetime. It puts the battery under a small load (350 ohms), so it gives a better indication of battery condition than a standard multimeter
Will do that tomorow that have Ben fine it just with me fitting new soler panel thought I would check them out
Bill
 
May 8, 2016
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Fair enough mate. Good luck with it, my turn with solar panels soon :(

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Snowbird

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Apr 24, 2009
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Although I have a drop tester I find the best way to check batteries is charge them over a 2 day period, leave them 24 hours, then take them in the car to Quickfit who have a free battery testing service, with a state of the art tester with printout and get them tested there.
 

jonandshell

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Dec 12, 2010
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Checking specific gravity against indicated cell voltage is a good guide to a battery's health.
 

Lenny HB

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Oct 18, 2007
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Best way of testing a leisure battery is to fully charge it, let it rest for an hour then & check the voltage:-
1) Place a load on it of say 5 amps (can do this in the van by turning on lights etc.).
2) Leave it with the load for a time that equates to 25% of battery capacity (100A/H battery it would be 5 amps for 5 hours).
3) Turn the load off let the battery settle for ½-1 hour measure the voltage, the battery will now be @ 75% state of charge.
4) Repeat 3, battery will now be @ 50% state of charge.
6) Repeat 3, battery will now be @ 25% state of charge. - not recommended to take a wet cell (standard battery) below 50% too often.

batt v.JPG

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