bcbullet said:
Yeah, I have made that mistake myself.
VanGrrl57
Ran my Trojans flat
- Thread starter bcbullet
- Start date
Help Support Van Living Forum:
Yeah, I have made that mistake myself.
VanGrrl57
SternWake
Well-known member
- Joined
- Nov 30, 2013
- Messages
- 3,874
- Reaction score
- 2
Another Van dweller, with an overwhelmingly inadequate electrical system, just gave me his 6 month old group27 Duralast ( made by johnson controls, in Mexico) starting battery to recharge.
I found it at 7.33 volts, and had to parallel it with another charged battery and hook Automatic 'smart' charger to start. Later I will bust out my Meanwell power supply and bring it to 16.2v for as long as required to max out specific gravity.
His charging strategy was start the engine and idle it for 10 minutes every two weeks.
Poor battery.
All the fuses in his ciggy plugs started blowing, Likely as at such a low voltage, the amperage draw increased beyond the rating of the fuse.
I'll get the battery fully charged, but I would not want to guarantee this battery. He really overpaid for this battery. It is by far the lightest weight group 27 I have ever lifted. I hope the obviously super thin sparse plates do not dissolve while I am charging it. The battery only has 620CCA. I'd expect a group 27 starting battery to have 120 more CCA than that. My Northstar AGM-27 is rated at 930CCA.
He should really have shopped around. HE claims it was 150$ not including core charge.
I found it at 7.33 volts, and had to parallel it with another charged battery and hook Automatic 'smart' charger to start. Later I will bust out my Meanwell power supply and bring it to 16.2v for as long as required to max out specific gravity.
His charging strategy was start the engine and idle it for 10 minutes every two weeks.
Poor battery.
All the fuses in his ciggy plugs started blowing, Likely as at such a low voltage, the amperage draw increased beyond the rating of the fuse.
I'll get the battery fully charged, but I would not want to guarantee this battery. He really overpaid for this battery. It is by far the lightest weight group 27 I have ever lifted. I hope the obviously super thin sparse plates do not dissolve while I am charging it. The battery only has 620CCA. I'd expect a group 27 starting battery to have 120 more CCA than that. My Northstar AGM-27 is rated at 930CCA.
He should really have shopped around. HE claims it was 150$ not including core charge.
SternWake
Well-known member
- Joined
- Nov 30, 2013
- Messages
- 3,874
- Reaction score
- 2
John61CT said:
No, but he really has few options. His van is old, the alternator likely rated at 45 amps or less.
His battery cables, ...... Ugh. Can't really tell him anything though, he already knows........
Battery appears to have responded well just with a few schumacher restarts after bleeding off surface charge. The 4 amp load I was using to bleed off surface charge was taking forever to drag voltage below 12.8v so the shumacher would actuallty attempt to reseek absorption voltage.
Have not yet dipped hydrometer on it. Been charging for a solid 18 hours
SternWake
Well-known member
- Joined
- Nov 30, 2013
- Messages
- 3,874
- Reaction score
- 2
Some people you can't help to help themselves. He has a large issue with funds, and unwise use of those he does have.
I've presented some options regarding solar, but he already knows everything and what to do, and how to do it.........
I've presented some options regarding solar, but he already knows everything and what to do, and how to do it.........
Dunning-Kruger dictates we are all like that, in those topic domains where we know so little, that we don't even know how much we don't know.
As Rumsfeld put it, the "unknown unknowns"
Some areas are so deep, the more you learn, the tinier the proportion you're sure about gets, until you realize it's "turtles all the way down".
As we know, there are known knowns; there are things we know we know. We also know there are known unknowns; that is to say we know there are some things we do not know. But there are also unknown unknowns—the ones we don’t know we don’t know.
As Rumsfeld put it, the "unknown unknowns"
Some areas are so deep, the more you learn, the tinier the proportion you're sure about gets, until you realize it's "turtles all the way down".
As we know, there are known knowns; there are things we know we know. We also know there are known unknowns; that is to say we know there are some things we do not know. But there are also unknown unknowns—the ones we don’t know we don’t know.
SternWake
Well-known member
- Joined
- Nov 30, 2013
- Messages
- 3,874
- Reaction score
- 2
My 'smart' schumacher sc2500a, became so smart, it would no longer to continue to charge the battery. It would flash the green light and go right into float at 13.6v on the agm setting. 0.17 amps. It was taking way too long for my 4 amp load to reduce battery voltage so that the charger could be restarted so it would again seek 14.7ish volts.
When I did finally get it restarted, 12 amps skyrocketed voltage past the mid 15's, then shut off and start flashing error red lights.
The 2 amp setting could not get it over 14 volts. So the charger was at this point worthless in the goal of fully charging this battery.
So, I got my Meanwell power supply, set it to 14.9v and let er rip. 5 amps. An hour later it was 4.6 amps, another hour, 3.75 amps. I thought it should have tapered more in that time.
Out comes the battery polygraph, the hydrometer. The best cell read 1.210, well 1.220 but -12 for cold electrolyte temperature so more like 1.208. Healthy would be 1.270 or higher.
So going by post charging voltage, and then the 4 amp load extreme slow reduction in voltage, the battery still seemed pretty strong. The hydrometer proved otherwise.
I bumped up voltage in increments keeping it at around 5 amps and eventually got to 15.89v over the next hour.
Another specific gravity check and found only 3 of the 6 cells had improved slightly, to a compensated 1.225. The other 3 cells were still 1.208
. I bumped voltage to 16.2v. 9+ amps were required. Battery was bubbling vigorously and gurgling, and it was very stinky despite very strong cross ventilation.
15 minutes later there was no more improvement in Specific gravity, and I just then got a text from the battery owner. I delivered it warm off the charger basically saying that it was not responding well but was fully charged as it was likely ever going to be again.
He said it was brand new, despite the 7/16 sticker on it, that it was a good strong battery, despite the pathetic specific gravity. He now claimed to start it every morning and idles for 20 minutes, but he ran out of gas and that's why he drained it to 7 volts.
I told him 10.5v is 100% discharged for a 12v battery, but he obviously saw otherwise. Does not matter, he has no voltmeter.
I said he could likely draw it to 7 volts maybe 5 more times before it would not retain enought charge to be a functional starting battery. He then said he'd just warranty it.
'Not the battery, nor retailers, fault' I muttered.
Later I returned to my workshop/shed. I had put the Meanwell on my former Van battery, a USbattery group31 flooded 12v that I took out of van service in 2015 after nearly 500 deep cycles in 18 months.
It now lives a pretty easy life and rarely gets discharged below 80%. I had put the meanwell on it at 14.9v( 55 degree battery) and left it while I delivered the other battery. When I returned it was accepting 2.33 amps ar 14.91v, and I checked Specific gravity on all cells.
The weak cell was still weak, at 1.255, but the other 5 were all in the green at 1.270 or higher. So it was really close to 100%, but I bumped it upto 15.3v, then did the constant 5 amp thing upto 16v, and then read 1.260 on the weak cell, and the others were all 1.280 or higher. I then reduced voltage to 13.6v.
So, this old worn out group31 of mine. It has over 500 deep cycles on it, likely several hundred shallow cycles, is nearly 38 months old, and is in better condition than a 6 month old starting battery that has been abused since day one.
When I did finally get it restarted, 12 amps skyrocketed voltage past the mid 15's, then shut off and start flashing error red lights.
The 2 amp setting could not get it over 14 volts. So the charger was at this point worthless in the goal of fully charging this battery.
So, I got my Meanwell power supply, set it to 14.9v and let er rip. 5 amps. An hour later it was 4.6 amps, another hour, 3.75 amps. I thought it should have tapered more in that time.
Out comes the battery polygraph, the hydrometer. The best cell read 1.210, well 1.220 but -12 for cold electrolyte temperature so more like 1.208. Healthy would be 1.270 or higher.
So going by post charging voltage, and then the 4 amp load extreme slow reduction in voltage, the battery still seemed pretty strong. The hydrometer proved otherwise.
I bumped up voltage in increments keeping it at around 5 amps and eventually got to 15.89v over the next hour.
Another specific gravity check and found only 3 of the 6 cells had improved slightly, to a compensated 1.225. The other 3 cells were still 1.208
. I bumped voltage to 16.2v. 9+ amps were required. Battery was bubbling vigorously and gurgling, and it was very stinky despite very strong cross ventilation.
15 minutes later there was no more improvement in Specific gravity, and I just then got a text from the battery owner. I delivered it warm off the charger basically saying that it was not responding well but was fully charged as it was likely ever going to be again.
He said it was brand new, despite the 7/16 sticker on it, that it was a good strong battery, despite the pathetic specific gravity. He now claimed to start it every morning and idles for 20 minutes, but he ran out of gas and that's why he drained it to 7 volts.
I told him 10.5v is 100% discharged for a 12v battery, but he obviously saw otherwise. Does not matter, he has no voltmeter.
I said he could likely draw it to 7 volts maybe 5 more times before it would not retain enought charge to be a functional starting battery. He then said he'd just warranty it.
'Not the battery, nor retailers, fault' I muttered.
Later I returned to my workshop/shed. I had put the Meanwell on my former Van battery, a USbattery group31 flooded 12v that I took out of van service in 2015 after nearly 500 deep cycles in 18 months.
It now lives a pretty easy life and rarely gets discharged below 80%. I had put the meanwell on it at 14.9v( 55 degree battery) and left it while I delivered the other battery. When I returned it was accepting 2.33 amps ar 14.91v, and I checked Specific gravity on all cells.
The weak cell was still weak, at 1.255, but the other 5 were all in the green at 1.270 or higher. So it was really close to 100%, but I bumped it upto 15.3v, then did the constant 5 amp thing upto 16v, and then read 1.260 on the weak cell, and the others were all 1.280 or higher. I then reduced voltage to 13.6v.
So, this old worn out group31 of mine. It has over 500 deep cycles on it, likely several hundred shallow cycles, is nearly 38 months old, and is in better condition than a 6 month old starting battery that has been abused since day one.
Similar threads
