Second leisure battery debate / challenge.

jacquigem said:
Interestingly there is a sticker on my sargent control panel which says do not discharge below 10.5 volts or it may damage batteries. I have always thought that would be far too low. I wonder why it's there ?
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People are learning more as time goes by, id not go below 12.2v on standard l acids, lead carboncould go down a bit more with no trouble.
 
Nabsim said:
Well my 3x90ah Bosch PowerFrame battery’s were useless within 12 months from new solely taking too much out of them. Not that many times either but allied to the fact you rarely get them to full capacity unless using hookup most folks won’t have 110ah on a 110ah battery very often if at all.

I would always recommend not taking lead acid too low and work on 50% of stated capacity
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You'll never know what was the largest contributing factor that knackered your batteries Neil, the deep discharges wouldn't have helped for sure but sitting partially charged would be quite significant also as you suggest. If you'd have only taken them to 50% would you have got more than twice the life? Maybe, maybe not but you'd need 6 batteries for the same effective OP and be carrying twice the weight around, you'd also take up twice the space which is a huge factor in a MH.
People and society like to have simple answers to complicated questions. What speed is safe through a village? 30mph? NO not really, 25mph would be safer yes? and 20 safer still, true? Would 31mph be so much worse than 30? No not really but we need a number so 30 it is! Just like smoking or drinking there's no amount of fags or booze that's safe and no amount that'll kill you, the fact is the more you drink or smoke the more you're risking it. Recommending 50% discharge is like saying a pack a week and 2 bottles of wine a week is my recommendation, it makes little sense apart from giving people a sense of 'what's ok' so they feel content about what they do.
How many times have you seen "Lithium batteries have twice the effective power because you can only discharge lead acid to 50% posted?
The problem is the 50% guideline is touted that often that it goes from a guide to a law.
It was only yesterday that David and myself posted on this exact same subject on another tread on here.
 
merl said:
You'll never know what was the largest contributing factor that knackered your batteries Neil, the deep discharges wouldn't have helped for sure but sitting partially charged would be quite significant also as you suggest. If you'd have only taken them to 50% would you have got more than twice the life? Maybe, maybe not but you'd need 6 batteries for the same effective OP and be carrying twice the weight around, you'd also take up twice the space which is a huge factor in a MH.
People and society like to have simple answers to complicated questions. What speed is safe through a village? 30mph? NO not really, 25mph would be safer yes? and 20 safer still, true? Would 31mph be so much worse than 30? No not really but we need a number so 30 it is! Just like smoking or drinking there's no amount of fags or booze that's safe and no amount that'll kill you, the fact is the more you drink or smoke the more you're risking it. Recommending 50% discharge is like saying a pack a week and 2 bottles of wine a week is my recommendation, it makes little sense apart from giving people a sense of 'what's ok' so they feel content about what they do.
How many times have you seen "Lithium batteries have twice the effective power because you can only discharge lead acid to 50% posted?
The problem is the 50% guideline is touted that often that it goes from a guide to a law.
It was only yesterday that David and myself posted on this exact same subject on another tread on here.
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My bad, it was THIS thread!!🤪
 
We had 3 x 100ah Lucas flooded lead acid in the transit
Charged via 200w of solar
And a Durite VSR/High output alternator ...

Running our 300w mod sine wave inverter for cooking (slow cooker/microwave/toaster/kettle)
As well as lighting/tv/eberspacher and 12v compressor cool box ...

Never had hook up on it barring in winter when I stuck a 7 stage intelligent charger on it now and again to top the batteries up ...

Those 3 batteries are still doing sterling service holding a good charge in the greenhouse powering a stand alone diesel heater some 7 years or so later .
 
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mistericeman said:
We had 3 x 100ah Lucas flooded lead acid in the transit
Charged via 200w of solar
And a Durite VSR/High output alternator ...

Running our 300w mod sine wave inverter for cooking (slow cooker/microwave/toaster/kettle)
As well as lighting/tv/eberspacher and 12v compressor cool box ...

Never had hook up on it barring in winter when I stuck a 7 stage intelligent charger on it now and again to top the batteries up ...

Those 3 batteries are still doing sterling service holding a good charge in the greenhouse powering a stand alone diesel heater .
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Never knew you could get such low wattage appliances? 300W toaster?? Did it actually toast anything or just get it warm? 😬 I think I'd have gave up waiting for a cup of tea and cracked open a bottle!
 
merl said:
Never knew you could get such low wattage appliances? 300W toaster?? Did it actually toast anything or just get it warm? 😬 I think I'd have gave up waiting for a cup of tea and cracked open a bottle!
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Typo ....should've been 3000w before spell check got hold of it
 
The 95 ltr compressor fridge I fitted lasts 3 days without starting engine. 135 amp battery (new) low sun and very little solar.
Auto switch off on fridge at 11.5 volt
 
jacquigem said:
Interestingly there is a sticker on my sargent control panel which says do not discharge below 10.5 volts or it may damage batteries. I have always thought that would be far too low. I wonder why it's there ?
Click to expand...
A Lead Acid battery is considered fully flat - 100% Discharged - at 10.8V. That does apply to all the various Lead Acid battery types including Wet Cell, VRLA, AGM, Gel, Lead Carbon and all the various combinations of the above.

I wonder if that sticker was added to the Control Panel by the Motorhome Dealer as the standard low voltage alarm on the Sargent which people may otherwise rely on is far too low (10.5V is also much too low anyway as you suspect).

Something to bear in mind when looking at the voltage chart that Trev posted .... These would be the RESTING voltage for the given State of Charge. When the battery is in use, the voltage sags - and the higher the current the greater the sag. It is not unusual for a well charged battery to dip below 12V under a high low and that is no problem. This is why Inverters have relatively low cutout voltages. Voltages are not the best way to keep an eye on battery state of charge - a proper State of Charge monitor is not an expensive item and should be considered by anyone who is going to make good use of the batteries installed.
 
I have the grill and little oven, plus one of those silly paramid things for over the rings, not tried as yet.
My we over goes on cartridge gas and the main cooker on alugas refillable.
whats for dinner.png
well set out.png
 
wildebus said:
A Lead Acid battery is considered fully flat - 100% Discharged - at 10.8V. That does apply to all the various Lead Acid battery types including Wet Cell, VRLA, AGM, Gel, Lead Carbon and all the various combinations of the above.

I wonder if that sticker was added to the Control Panel by the Motorhome Dealer as the standard low voltage alarm on the Sargent which people may otherwise rely on is far too low (10.5V is also much too low anyway as you suspect).

Something to bear in mind when looking at the voltage chart that Trev posted .... These would be the RESTING voltage for the given State of Charge. When the battery is in use, the voltage sags - and the higher the current the greater the sag. It is not unusual for a well charged battery to dip below 12V under a high low and that is no problem. This is why Inverters have relatively low cutout voltages. Voltages are not the best way to keep an eye on battery state of charge - a proper State of Charge monitor is not an expensive item and should be considered by anyone who is going to make good use of the batteries installed.
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Can you suggest one please David?
 
wildebus said:
A Lead Acid battery is considered fully flat - 100% Discharged - at 10.8V. That does apply to all the various Lead Acid battery types including Wet Cell, VRLA, AGM, Gel, Lead Carbon and all the various combinations of the above.

I wonder if that sticker was added to the Control Panel by the Motorhome Dealer as the standard low voltage alarm on the Sargent which people may otherwise rely on is far too low (10.5V is also much too low anyway as you suspect).

Something to bear in mind when looking at the voltage chart that Trev posted .... These would be the RESTING voltage for the given State of Charge. When the battery is in use, the voltage sags - and the higher the current the greater the sag. It is not unusual for a well charged battery to dip below 12V under a high low and that is no problem. This is why Inverters have relatively low cutout voltages. Voltages are not the best way to keep an eye on battery state of charge - a proper State of Charge monitor is not an expensive item and should be considered by anyone who is going to make good use of the batteries installed.
Click to expand...
Thanks,
I suspected that the sticker had been added by someone ?
Whilst we are talking batteries I wondered what your view was of the amp hours reading I get from the sargent control as it does not seem to tally with the voltage readings my victron controller provides , especially on hook up.
When at home and using hook up to recharge , the amp hours often drop dramatically, but victron is saying batteries fine ?
 
jacquigem said:
Thanks,
I suspected that the sticker had been added by someone ?
Whilst we are talking batteries I wondered what your view was of the amp hours reading I get from the sargent control as it does not seem to tally with the voltage readings my victron controller provides , especially on hook up.
When at home and using hook up to recharge , the amp hours often drop dramatically, but victron is saying batteries fine ?
Click to expand...
I don't recall the readings you mention? have you a link to that post where you showed them?
 
wildebus said:
I don't recall the readings you mention? have you a link to that post where you showed them?
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Sorry no, I haven't supplied readings but what I have noticed is that the amp hours reading often drops to zero and then build back up to 100 per cent even when on hook up recharging .I just assumed it must be faulty and ignore them , especially now I have a victron controller fitted which tells me voltage is ok ?
 
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