Battery tester (1 Viewer)

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Oct 23, 2009
790
615
Anglesey North Wales
Funster No
9,010
MH
Adria Twin 640SLB
Exp
Since 2010
I am having a torrid time with my batteries at the moment with very annoying sudden voltage drops therefore to prove categorically that the batteries are either good or bad is there a bit of testing equipment out there that can be used without resorting to load testing the battery with a 5 amp bulb and monitoring voltage drop over hours. I’m aware that the Topdon tester I use on car batteries cannot be used on leisure batteries . Tia
 

Lenny HB

LIFE MEMBER
Oct 18, 2007
56,123
164,373
On the coast in West Sussex
Funster No
658
MH
Carthago Compactline
Exp
Since 2008 & many years tugging
I think there is a new tester that does a leisure battery test as well as CCA test but it not cheap as it's a bit of professional kit.

Cant really go wrong with a slow discharge test.
 
Sep 24, 2013
1,351
792
Norwich
Funster No
28,255
MH
Carthago A class
Exp
Since 2014
I bought an electronic load tester on eBay for about £40. Can set discharge current up to 10A and the cutoff voltage to terminate the test. Has some quirks but I’ve used it to check a couple of leisure and cab batteries. Checked with a load of C/20, so about 4.5A.

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Lenny HB

LIFE MEMBER
Oct 18, 2007
56,123
164,373
On the coast in West Sussex
Funster No
658
MH
Carthago Compactline
Exp
Since 2008 & many years tugging
I bought an electronic load tester on eBay for about £40. Can set discharge current up to 10A and the cutoff voltage to terminate the test. Has some quirks but I’ve used it to check a couple of leisure and cab batteries. Checked with a load of C/20, so about 4.5A.
That sounds good, do you have a link?
I just turn a few things on in the van.
 
Sep 24, 2013
1,351
792
Norwich
Funster No
28,255
MH
Carthago A class
Exp
Since 2014
EBay item number 394398984026

Not my actual one, in fact a bit better and cheaper!
 
OP
OP
wp1234
Oct 23, 2009
790
615
Anglesey North Wales
Funster No
9,010
MH
Adria Twin 640SLB
Exp
Since 2010
I think there is a new tester that does a leisure battery test as well as CCA test but it not cheap as it's a bit of professional kit.

Cant really go wrong with a slow discharge test.
Camper UK say they have a leisure battery tester ( a Sealey product I believe ) so have booked in for a test on both GELs on my way home from Portugal, I hope they know what they are doing 😂. Would you have a link to the slow discharge test voltages on GEL batts please.

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Nov 2, 2022
471
587
Gloucestershire, UK
Funster No
92,219
MH
Burstner Eliseo C602
Exp
Since 2016
As an aside, I like how they show the mains adaptor as a 'free gift'! It is actually illegal to place electrical products onto the UK market without a standard compliant 13A plug fitted. A conversion plug can be used but adaptors such as this are not accepted. In other words, this product as supplied is illegal.
 

Lenny HB

LIFE MEMBER
Oct 18, 2007
56,123
164,373
On the coast in West Sussex
Funster No
658
MH
Carthago Compactline
Exp
Since 2008 & many years tugging
Camper UK say they have a leisure battery tester ( a Sealey product I believe ) so have booked in for a test on both GELs on my way home from Portugal, I hope they know what they are doing 😂. Would you have a link to the slow discharge test voltages on GEL batts please.
1676577978308(1).png
 
OP
OP
wp1234
Oct 23, 2009
790
615
Anglesey North Wales
Funster No
9,010
MH
Adria Twin 640SLB
Exp
Since 2010
As an aside, I like how they show the mains adaptor as a 'free gift'! It is actually illegal to place electrical products onto the UK market without a standard compliant 13A plug fitted. A conversion plug can be used but adaptors such as this are not accepted. In other words, this product as supplied is illegal.
What’s the difference between an adaptor and a conversion plug…. and why are they not safe ? just curious .
 
Sep 24, 2013
1,351
792
Norwich
Funster No
28,255
MH
Carthago A class
Exp
Since 2014
I have yet to find a figure to terminate the discharge test with. All the tables I have seen are state of charge versus rested voltage, not voltage under load. I have used 11.8v as a terminating voltage at C/20 discharge rate and found the after test resting voltage to be about right (only discharge a LA battery to 50%). If anyone has a more accurate figure then I would be interested to hear.

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Nov 2, 2022
471
587
Gloucestershire, UK
Funster No
92,219
MH
Burstner Eliseo C602
Exp
Since 2016
What’s the difference between an adaptor and a conversion plug…. and why are they not safe ? just curious .
A conversion plug (or over plug) is a one time fitted item which requires tools to fit and is not readily removable. It is fitted by the manufacturer/importer/UK distributor. An example is shown below to convert a flat 2 pin EU plug. Over styles are available.

For this particular power meter, a power supply with a BS1363 13A pin configuration should be supplied as it can obviously not be over plugged.


overplug.png
 
Dec 2, 2019
3,886
8,591
Amersham
Funster No
67,145
MH
van conversion
Exp
Since 2019
I have yet to find a figure to terminate the discharge test with. All the tables I have seen are state of charge versus rested voltage, not voltage under load. I have used 11.8v as a terminating voltage at C/20 discharge rate and found the after test resting voltage to be about right (only discharge a LA battery to 50%). If anyone has a more accurate figure then I would be interested to hear.
Termination voltage for capacity test under C/10 discharge is 1.75vpc. Times that by 6= 10.5v. You have to have a charge source at ready if you do a true complete capacity discharge test. The battery can not be left at 10.5v longer than 10 mins. Also the test has to be done at 20 degC to be conclusive, few deg lower, and values will be flawed.
 

bigtwin

LIFE MEMBER
Oct 29, 2009
5,704
10,946
Derby
Funster No
9,111
MH
Concorde
Exp
Since 2006
A ‘drop’ tester can be revealing, quick and cheap to buy

Such a test will tell you nothing about whether the battery has lost a significant proportion of its capacity.

A battery may pass a drop test but have only half its nominal capacity (i.e. knackerd).

Ian
 

TheBig1

Deceased RIP
Nov 27, 2011
17,851
44,361
Dorset
Funster No
19,048
MH
A class
Exp
many many years! since I was a kid
if you want a decent capacity tester, think 4 figures. One place I know has them and will often do a test cheaply is a mobility scooter repair place. The tester is connected to a laptop and the report and graph can be printed out.
 
Sep 24, 2013
1,351
792
Norwich
Funster No
28,255
MH
Carthago A class
Exp
Since 2014
Termination voltage for capacity test under C/10 discharge is 1.75vpc. Times that by 6= 10.5v. You have to have a charge source at ready if you do a true complete capacity discharge test. The battery can not be left at 10.5v longer than 10 mins. Also the test has to be done at 20 degC to be conclusive, few deg lower, and values will be flawed.
Is that to discharge to 50%? I wouldn’t like to any further than that.

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Dec 2, 2019
3,886
8,591
Amersham
Funster No
67,145
MH
van conversion
Exp
Since 2019
Is that to discharge to 50%? I wouldn’t like to any further than that.
How do you know when is at 50% SOC? The figures I mentioned it says total capacity, as in the lot. It’s the only true test for it’s entire capacity.
 
Dec 2, 2019
3,886
8,591
Amersham
Funster No
67,145
MH
van conversion
Exp
Since 2019
if you want a decent capacity tester, think 4 figures. One place I know has them and will often do a test cheaply is a mobility scooter repair place. The tester is connected to a laptop and the report and graph can be printed out.
You can get a chargery, or a zke, with full pc graph to show charge and discharge etc, for about 150 quid.
 

TheBig1

Deceased RIP
Nov 27, 2011
17,851
44,361
Dorset
Funster No
19,048
MH
A class
Exp
many many years! since I was a kid
really? God they have come down in price since I last looked
 
Nov 13, 2011
1,559
5,750
Lincolnshire
Funster No
18,889
MH
PVC
Exp
30 years
Termination voltage for capacity test under C/10 discharge is 1.75vpc. Times that by 6= 10.5v. You have to have a charge source at ready if you do a true complete capacity discharge test. The battery can not be left at 10.5v longer than 10 mins. Also the test has to be done at 20 degC to be conclusive, few deg lower, and values will be flawed.
I agree Raul, I always use 10.5v as the cut-out.

Geoff
 
Sep 24, 2013
1,351
792
Norwich
Funster No
28,255
MH
Carthago A class
Exp
Since 2014
How do you know when is at 50% SOC? The figures I mentioned it says total capacity, as in the lot. It’s the only true test for it’s entire capacity.
50%. After the discharge test I let th battery rest for an hour or so and measure the voltage. Using a table such as Lenny posted above gives me the state of charge. Needs a few goes of trial and error (starting high terminating voltage and decreasing). Also need to do correction for temperature as was mentioned.

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Apr 27, 2016
7,417
8,848
Manchester
Funster No
42,762
MH
A class Hymer
Exp
Since the 80s
There is a calculation method, which has a few steps to give you the true battery capacity. First charge the battery to 100%. Then take out a known number of amp-hours. Let the battery rest and measure the resting voltage.

Use the chart to find the remaining % charge in the battery. Subtract from 100 to find the % charge taken out by the load, ie the percentage fall from the 100% level..

The Amp-hours drawn (A) represents the percentage fall (P) of the true charge capacity (C).
A amp-hours is P % of C, or as a formula,
A = (P/100) x C which can be rearranged to give
C = 100 x A / P

True Capacity = 100 x Amp-hours drawn / Percentage fall.

For example, if you take 40Ah out of a full battery, and its final charger level is 55%, then the charge level has fallen by 100 - 55 = 45%. The true capacity is 100 x 40 / 45 = 88Ah.

So if it's 90Ah on the battery label, it's fine. If it's 110Ah on the label then it's more of a concern. the capacity has dropped to 100 x 88 / 110 = 80% of its label value.
 
Nov 13, 2011
1,559
5,750
Lincolnshire
Funster No
18,889
MH
PVC
Exp
30 years
I bought an electronic load tester on eBay for about £40. Can set discharge current up to 10A and the cutoff voltage to terminate the test. Has some quirks but I’ve used it to check a couple of leisure and cab batteries. Checked with a load of C/20, so about 4.5A.
HI
I have just looked at a few of these on ebay and for some reason ebay have removed the user manual? So how difficult are they to actually use? I have looked at instructions on other sites, all in Chinese/English and it is about as clear as mud to me.

Geoff
 
Sep 24, 2013
1,351
792
Norwich
Funster No
28,255
MH
Carthago A class
Exp
Since 2014
HI
I have just looked at a few of these on ebay and for some reason ebay have removed the user manual? So how difficult are they to actually use? I have looked at instructions on other sites, all in Chinese/English and it is about as clear as mud to me.

Geoff
Mine came with instructions. All be it a bit Chenglish! I found a couple of videos on Youtube which I watched before buying.
Try this one which was the model I bought.



The ebay one I tagged has a colour display and a second set of input connectors to monitor the source voltage separate to the current carrying input which is preferred as it takes account of the voltage drop across the current carrying leads.

Another review of mine:


Other reviews of the colour display ones are also on Youtube.
 
Nov 13, 2011
1,559
5,750
Lincolnshire
Funster No
18,889
MH
PVC
Exp
30 years
Mine came with instructions. All be it a bit Chenglish! I found a couple of videos on Youtube which I watched before buying.
Try this one which was the model I bought.



The ebay one I tagged has a colour display and a second set of input connectors to monitor the source voltage separate to the current carrying input which is preferred as it takes account of the voltage drop across the current carrying leads.

Another review of mine:


Other reviews of the colour display ones are also on Youtube.

Hi
Thanks for the video links. I also found this web page Chinese or English, which actually explains it quite well.https://www.banber.com/banber/637ed0ac186c0a54da90cca0

Geoff

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