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Topic: How to load test house batteries? (Read 899 times) previous topic - next topic

How to load test house batteries?

I have 3 8G8D MK gel cells and am unsure of the date.  They seem to be ok overnight but what is the best way to do a load test?

Another question for you solar guys:  what voltages are you set for bulk, absorb, and float for gel cells?
Thanks!
Forest & Cindy Olivier
1987 log cabin
2011 Roadtrek C210P
no longer 1999 36' U320 build #5522
2013 Rzr 570 & 2018 Ranger XP1000
2006 Lexus GX470
2011 Tahoe LT 4x4
Previous 1998 45' 2 slide Newell, 1993 39' Newell

Re: How to load test house batteries?

Reply #1 –
Can you take them to a shop that sells alot of similar batteries,they should be able to test them.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: How to load test house batteries?

Reply #2 –
In Tucsun we had a local battery supply company bring their tester to our coach and do the load test there.  I think we paid about $150.00.  Those 8Ds are heavy.
Scott & Carol Seibert
2001 42' double slide U320 - Sold
Previous - 2002 36' U320

Re: How to load test house batteries?

Reply #4 –
I drove to a NAPA store, disconnected the grounds and they came out and tested the house batteries for free.  Their handheld test equipment printed out the results.  They need to know the make and model # of the battery.
Jerry Whiteaker former owner 96 U270  36' #4831 Austin,TX-Owner Mods LCD TV w/front cabinet rebuild - LCD TV bedroom - Dual Central AC, either can cool coach w 30 amp - Skylights at roof AC openings - Drop ceiling for ducting of AC - Shower skylight white gelcoat/wood/epoxy frame - Air Springs/Shocks replaced - 2014 CRV - 8K Home Solar - Chevy Volt

Re: How to load test house batteries?

Reply #5 –
I'm familiar with carbon pile load testers, but is this the recommended method to test the amphour capacity of our 8d gel cell house batteries?
Forest & Cindy Olivier
1987 log cabin
2011 Roadtrek C210P
no longer 1999 36' U320 build #5522
2013 Rzr 570 & 2018 Ranger XP1000
2006 Lexus GX470
2011 Tahoe LT 4x4
Previous 1998 45' 2 slide Newell, 1993 39' Newell

Re: How to load test house batteries?

Reply #6 –
Quote from: folivier –
I'm familiar with carbon pile load testers, but is this the recommended method to test the amphour capacity of our 8d gel cell house batteries?
If you have upgraded your inverter/charger to a modern one with a battery management system (Magnum, Victron, etc), it can tell you how many amp hours you've used at any given voltage.  You can see from that if you're getting the rated life from your batteries.  If you have the OEM charging system, probably the Heart system in '99, you won't see that info.  I suppose you could use a clamp meter to measure amp hours and a volt meter to accomplish almost the same thing manually.

Re: How to load test house batteries?

Reply #7 –
Quote from: folivier –
I'm familiar with carbon pile load testers, but is this the recommended method to test the amphour capacity of our 8d gel cell house batteries?
A carbon pile load tester will work, but you can also use a battery tester such as the OTC 3167 HP. I do not know how to post a link but just Google. They are expensive but useful to have. I have had one for years. Found it to be very accurate.
Larry and Terry
Ex 2004 U270 36'

Re: How to load test house batteries?

Reply #8 –
I have an AutoMeter SB5/2.  Found it on eBay for $160.  It does a lot of tests.

Test at 3x amp hr rating for 15 seconds.  That is like 750 amps for 15 seconds for an 8D.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: How to load test house batteries?

Reply #9 –
Victron Blue Solar Charge Controller Specs.  Defaults.
They are adjustable by the end user for battery types.

From Victron ...
1.7 Flexible charge algorithm
Fully programmable charge algorithm, and eight preprogrammed algorithms, selectable with a rotary switch.
1.8 Adaptive three step charging
The BlueSolar MPPT Charge Controller is configured for a three step charging process: Bulk – Absorption – Float.
A regular equalization charge can also be programmed: see section 3.8 of this manual.
1.8.1. Bulk
During this stage the controller delivers as much charge current as possible to rapidly recharge the batteries.
1.8.2. Absorption
When the battery voltage reaches the absorption voltage setting, the controller switches to constant voltage mode.
When only shallow discharges occur the absorption time is kept short in order to prevent overcharging of the battery. After a deep discharge the absorption time is automatically increased to make sure that the battery is completely recharged. Additionally, the absorption period is also ended when the charge current decreases to less than 2A.
1.8.3. Float
During this stage, float voltage is applied to the battery to maintain it in a fully charged state.
1.8.4. Equalization
See section 3.8
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: How to load test house batteries?

Reply #10 –
Quote from: Carol & Scott –
In Tucsun we had a local battery supply company bring their tester to our coach and do the load test there.  I think we paid about $150.00.  Those 8Ds are heavy.
I was with Scott when he had his batteries tested. I did a write up of it here.

How to test 8D AGMs

see ya
ken
The selected media item is not currently available.ken & dori hathaway & Big Agnes
🍺1992 U300 GrandVilla WTBI #4150 FOT FBP 2011
✨6V-92TA DDEC Parlor Coach 350HP Series 92
🏁2011 Nissan XTerra Pro-4X

Re: How to load test house batteries?

Reply #11 –
Ken, I responded to your post regarding that test a year ago. Just as I responded to this post. My tester weighs 3 pounds, does not get hot, is simple to use, and test the batteries just as effective as the testers talked about. The draw back is the cost of about $500.
Larry and Terry
Ex 2004 U270 36'

Re: How to load test house batteries?

Reply #12 –
Why don't you turn on the inverter and run the microwave for 1 minute and then turn everything off. If you have a bad battery they will not recover at idle. Then you can disconnect them one at a time and do it again to find THE bad battery. That's load testing.
1994 U280, Build 4490
Deming, NM.

Re: How to load test house batteries?

Reply #13 –
Our coach has a magnum power pro round gage installed.

Records amps in and out.

We have 675 amp hours capacity nominally.  At 12.85 volts with no load for a day.

If you compare the gauges voltage versus amps used the two should match.

If you are at 12.2 volts and show 350 amp hours consumed then the voltage matches the used amp hours.

Easy if you install a gauge. 

The other posts here are to use a std load for x amount of hours then measure the resting batteries voltage.

Same idea,  the gauge is way easier. 
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4
 

Re: How to load test house batteries?

Reply #14 –
I thought that the load tester that was used, Ken's pics, looked like it was from the Flash Gorden's days.  :D
Scott & Carol Seibert
2001 42' double slide U320 - Sold
Previous - 2002 36' U320