Hi @aspiremr,
no, leave the load connected and just measure the voltage at the battery terminals.
cheers
Mike
no, leave the load connected and just measure the voltage at the battery terminals.
cheers
Mike
@mikerezny,
Unfortunately it is back to work tomorrow, so not able to monitor battery during the day. Also, obviously can't monitor overnight when asleep.
Do I just leave the load on overnight and while at work, and take readings in the morning or when I get home etc. Or should I disconnect the load when unattended and only run tests when i can be around and the test is somewhat continuous? Which would mean the testing is focussed on weekends?
Thanks.
MR
Unfortunately it is back to work tomorrow, so not able to monitor battery during the day. Also, obviously can't monitor overnight when asleep.
Do I just leave the load on overnight and while at work, and take readings in the morning or when I get home etc. Or should I disconnect the load when unattended and only run tests when i can be around and the test is somewhat continuous? Which would mean the testing is focussed on weekends?
Thanks.
MR
Hi @aspiremr,
just take the measurements when you can. 20 hours is a long time. Are you heading off next weekend or are you likely to be home?
I would suggest taking the last measurement before you go to bed and then disconnecting the load, wait a few minutes, and take a final voltage measurement with no load connected. Then put the battery back on charge until you get home from work tomorrow.
It is not a good idea to leave the discharge test running overnight until you have some idea of the capacity. You certainly do not want to completely flatten the battery.
You will need to keep track of each battery. I think Battery A was the left-hand battery and battery B was the right hand battery. Is that correct. If so, which battery is currently on the discharge test?
If you have time tomorrow afternoon, do a similar discharge test on the other battery until you go to bed, following the above instructions.
Then, if you have time, post the voltages and times you have recorded.
What was the battery voltage at the beginning of the discharge test and after an hour?
Also, post me the model number of the battery and I will try to download the specifications. Is it a Bosch battery?
Cheers
Mike
Hi @mikerezny ,
Battery A - currently under load testing.
Immediately off charger (9.00 am) 13.78 volts
After two hours off charger unloaded (10.50 am) 13.42 volts
55 watt globe connected at 11.00 am
First multimeter reading after only a few minutes
under load, still under load while taking reading 12.20 volts
Midday reading, taken under load 12.30 volts
1 pm reading, taken under load 12.23 volts.
2 pm reading, taken under load 12.21 volts
3 pm reading, taken under load 12.13 volts
4 pm reading, taken under load 12.05 volts
5 pm reading, taken under load 11.96 volts
6 pm reading, taken under load 10.99 volts
7 pm reading, taken under load 9.83 volts
Reading immediately after removing load 12.00 volts
Reading 30 minutes after removing load 12.10 volts
So, battery A is completely run down. apps 4.5 amps per hour, drained the battery completely in approx 8 hours. 8 times 4.5 equates to 36. Does that mean that my battery capacity is now only 36 amps?
Battery is Bosch model BG12 - 100. 12 Volt 96 Ah.
Last edited:
Even though your testing is incomplete, Battery A is still in good condition, lets see what Battery B is like.
Thanks @Bellbirdweb,
I'll not get to testing Battery B until next weekend. Not enough hours between now and Bed time to test, and then with work during the day I won't be able to be around the battery for any substantial length of time until next Saturday. Given that I figure I might as well extend the testing of Battery A for as long as possible??
Fingers crossed both are ok, that will solve one dilemma and mean lots of dollars available for other things.
Thanks for input.
MR
Hi @Bellbirdweb , looks pretty good for the first battery, but as you said, let's see what battery B is like. Then when all fitted back together again, the real test under proper load conditions. Looks like I could lose my money on what I thought batteries could handle after such abuse!!!
I've had pretty good success with bringing these batteries back to life using the ctek chargers.
Some are beyond help but provided they haven't been left too long they seem to respond pretty well.
Another quick side question. When I put the batteries on to charge on my Ctek charger, I just use the default mode. HOw do you know when you should use the recondition mode?
Thanks
MR
Hi @aspiremr,
can't help you with that. Hopefully some else will reply.
What was the model number of your Ctek charger? Or better still, can you point me at an online manual for it?
cheers
Mike
HI @mikerezny , It's a Ctek Multi XS 15000. I've had a read of the manual and it just says it if for deeply discharged batteries and to consult with battery manufacturer before using as high voltages can damage batteries .........
Hi @aspiremr,
were you able to measure the current going into the headlight globe?
If it is a 55W lamp, it should about 4.6A.
That means, every hour your discharge test is running, your battery capacity is increasing by about 5%. If it still going at 10pm, after 11 hours, you have about 55% of the rated capacity. If it is still going, I bet you won't be able to turn it off and go to bed
regards
Mike
were you able to measure the current going into the headlight globe?
If it is a 55W lamp, it should about 4.6A.
That means, every hour your discharge test is running, your battery capacity is increasing by about 5%. If it still going at 10pm, after 11 hours, you have about 55% of the rated capacity. If it is still going, I bet you won't be able to turn it off and go to bed
regards
Mike
Hi @aspiremr,
have you got the readings for 5pm and 6pm to share?
This is more fun than waiting for the election results, but not as much fun as watching each stage of the Tour de France
cheers
Mike
HI @mikerezny , No, couldn't check the AMP's. My Multi Meter only seems to have settings for Volts, Resistance, and Hertz???? Who makes a multi meter that doesnt measure amps. When I bought it a few months ago went to a specialist electrical supplies company, and they only had a choice of 2. This one which was about $40 and one for approx $300 aimed at auto electricians or other electrical professionals. At that stage I didn't really even understand what I was buying.Hi @aspiremr,
were you able to measure the current going into the headlight globe?
If it is a 55W lamp, it should about 4.6A.
That means, every hour your discharge test is running, your battery capacity is increasing by about 5%. If it still going at 10pm, after 11 hours, you have about 55% of the rated capacity. If it is still going, I bet you won't be able to turn it off and go to bed
regards
Mike
As for measuring and going to bed, big day at work tomorrow, and so while I would love to see how long it takes to get to fully flat, I know i won't cope at work tomorrow if I don't call it.
even though I won't be able to get it down to the 10 volts you mentioned previously, can't we draw conclusions about the health of the battery just by how well it is holding charge under load and how much voltage is left after so many hours of load?
Loving it, I am one of those guys who watches the kettle boil, so this is right up my alley. Only 4 minutes until the 5pm reading. I might secretly be taking readings on the half hour too, just to see, but not posting those.LOLHi @aspiremr,
have you got the readings for 5pm and 6pm to share?
This is more fun than waiting for the election results, but not as much fun as watching each stage of the Tour de France
cheers
Mike
I'm confused about one thing - LOL, if only. But one question at the moment.
55 watt globe, 12 volts, equals Amp draw of 4.6. Battery has been running for 6 hours now, so total draw would be approx 27 - 28 amps. That is only 30% of the battery capacity.
How does this relate to the idea that you can tell what capacity a battery is at based on it's voltage. So a little table I found tells me that 11.9 volts is 40% remaining capacity.
Drawing 28 amps out of a 96 Ah battery is only 29% of supposed capacity, but a voltage reading of 11.9 volts means I have drawn 60% out.
Is the only way to truly test the Amp hours capacity left in the battery by running the test you suggested to conclusion? @mikerezny, as in keep drawing until the battery is completely and absolutely empty and will not light the globe any more?
MR
ps - 5 pm reading added to thread now.
55 watt globe, 12 volts, equals Amp draw of 4.6. Battery has been running for 6 hours now, so total draw would be approx 27 - 28 amps. That is only 30% of the battery capacity.
How does this relate to the idea that you can tell what capacity a battery is at based on it's voltage. So a little table I found tells me that 11.9 volts is 40% remaining capacity.
Drawing 28 amps out of a 96 Ah battery is only 29% of supposed capacity, but a voltage reading of 11.9 volts means I have drawn 60% out.
Is the only way to truly test the Amp hours capacity left in the battery by running the test you suggested to conclusion? @mikerezny, as in keep drawing until the battery is completely and absolutely empty and will not light the globe any more?
MR
ps - 5 pm reading added to thread now.
The recondition cycle on a ctek uses a pulse system to help in suplhate cells.
This is really only useful on wet cell batteries and not really something that will work on a gel cell battery.
Deep discharge using your globe and recharging fully will get the best out of the batteries.