House batteries low after hours on the Genset

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House batteries low after hours on the Genset

June 09, 2019, 11:09:51 pm

Getting ready to head up to Joseph, Oregon in a week. So got the coach out and parked at the house. It was just a bit slow to crank over. Let it high idle till air built up and drove across town to fuel up. Got back to the house and started the Genset. Noticed that when I pushed the charge button on the link 2000. The gen voltage dropped a lot and was under quite the load. So I let in run in charge mode for 2 hours. Went out and saw "lobatt" flashing. Charger was still in charge mode.
As it was warm. I turned on both AC unit. Several seconds after getting back to the Link 2000 panel. I saw the voltage drop sharply and come back up while at the same time hearing a loud clunk from up front in the area of the inverter. So I turned the AC off and let the batteries charge another hour.

Went out and shut everything down and isolated each house battery one at a time to check voltage. All three are at 11.9. visually all the batteries look fine. I.E. They are not bloated. If anything thing, They look like they are under a vacuum. I have read the manual and I'm not sure where to start. Batteries are 3.5 year old O'Reilly's AGM Super Starts.

Re: House batteries low after hours on the Genset

Reply #1 – June 09, 2019, 11:13:44 pm

Sorry dead. Some or all. Or bad cabling

Re: House batteries low after hours on the Genset

Reply #2 – June 09, 2019, 11:16:51 pm

Be aware that smart charger will often NOT charge extremely deeply discharged/dead batteries.

You may need an old fashion "stupid" charger to get the process started.

I am a little surprised that the alternator did not pick them up enough that the smart charger would take over.

Re: House batteries low after hours on the Genset

Reply #3 – June 09, 2019, 11:19:37 pm

Quote from: Caflashbob – June 09, 2019, 11:13:44 pm

Sorry dead. Some or all. Or bad cabling

The cabling is pristine. I might take the coach to my local truck shop and do a batt test and see what that might say. Seems weird that all three would croak all at once.

Re: House batteries low after hours on the Genset

Reply #4 – June 09, 2019, 11:21:34 pm

Quote from: wolfe10 – June 09, 2019, 11:16:51 pm

Be aware that smart charger will often NOT charge extremely deeply discharged/dead batteries.

You may need an old fashion "stupid" charger to get the process started.

I am a little surprised that the alternator did not pick them up enough that the smart charger would take over.

I'll have the shop do a dumb charger and see what that does. Perhaps I'll go for a longer drive or set it on high idle on Monday.

Re: House batteries low after hours on the Genset

Reply #5 – June 09, 2019, 11:22:22 pm

You can NOT accurately test a dead battery. They must be fully charged to accurately load test them.

Re: House batteries low after hours on the Genset

Reply #6 – June 09, 2019, 11:29:51 pm

Quote from: wolfe10 – June 09, 2019, 11:22:22 pm

You can NOT accurately test a dead battery. They must be fully charged to accurately load test them.

Yep! I goofed.

It seems that if the voltage meter below the link panel was shown a large voltage drop 120 down to 90-100 when I pushed the charge button. It was "trying" to charge and was under a heck of a load to drop it that much. Only other thing that was on was the Fridge.

Re: House batteries low after hours on the Genset

Reply #7 – June 09, 2019, 11:34:09 pm

Too many things can cause voltage drop/surge in a generator.

More important would be to watch your inverter/charger monitor panel to see what voltage AND amps it shows to the house bank.

Re: House batteries low after hours on the Genset

Reply #8 – June 09, 2019, 11:46:40 pm

Quote from: wolfe10 – June 09, 2019, 11:34:09 pm

Too many things can cause voltage drop/surge in a generator.

More important would be to watch your inverter/charger monitor panel to see what voltage AND amps it shows to the house bank.

As I recall. The panel showed 12.8 V @ 110 Amps. I'll double check that in the AM. It's a bit late to run the genset.

Re: House batteries low after hours on the Genset

Reply #9 – June 10, 2019, 12:06:00 am

Quote from: bigdog – June 09, 2019, 11:46:40 pm

As I recall. The panel showed 12.8 V @ 110 Amps. I'll double check that in the AM. It's a bit late to run the genset.

That 110 amps means the inverter/charger WAS doing its job-- putting 110 amps into your house battery bank. Only 12.8 VDC with that high amp input means they were very deeply discharged.

Re: House batteries low after hours on the Genset

Reply #10 – June 10, 2019, 01:14:54 am

Quote from: wolfe10 – June 10, 2019, 12:06:00 am

That 110 amps means the inverter/charger WAS doing its job-- putting 110 amps into your house battery bank. Only 12.8 VDC with that high amp input means they were very deeply discharged.

Thanks Brett.
I'll fire up the genset on Monday and let it run the charger again and recheck the battery voltage. At that amperage, Maybe I'll set up a small house fan for the inverter/charger. Hopefully the batteries aren't toast.

Re: House batteries low after hours on the Genset

Reply #11 – June 10, 2019, 01:30:26 am

The charger should be able to handle the 110 amps

A desulfurization device can slowly restore sulphated agm's I understand.

Good luck

Re: House batteries low after hours on the Genset

Reply #12 – June 10, 2019, 01:46:37 am

I would disconnect the battery cables and check each battery voltage separately. It sounds like one may have a shorted cell. If one is significantly lower than the others, hook the other two back up leaving out the low one and try charging them. If they come up normally, you are better off leaving the bad one unplugged. If the two others take a full charge, have them tested and if they come up good, then consider getting one new one. It isn't ideal, but it may be a cost effective way to get more life out of the two that test good, at the cost of prematurely aging the new one.
Don

Re: House batteries low after hours on the Genset

Reply #13 – June 10, 2019, 02:04:20 am

Quote from: Don & Tys – June 10, 2019, 01:46:37 am

I would disconnect the battery cables and check each battery voltage separately. It sounds like one may have a shorted cell. If one is significantly lower than the others, hook the other two back up leaving out the low one and try charging them. If they come up normally, you are better off leaving the bad one unplugged. If the two others take a full charge, have them tested and if they come up good, then consider getting one new one. It isn't ideal, but it may be a cost effective way to get more life out of the two that test good, at the cost of prematurely aging the new one.
Don

Don, I disconnected each battery and checked the voltage. All three were at 11.9 on my volt meter and this was after two-three hours of charging at 110 amps@12.8 volts. None of the batteries was swollen showing off gassing nor were they hot. They look caved in. I went to the coach to plug it into 120 to run the fridge 3 hours after I stopped charging. The panel showed 12.1.

Re: House batteries low after hours on the Genset

Reply #14 – June 10, 2019, 02:31:16 am

Quote from: bigdog – June 10, 2019, 02:04:20 am

Don, I disconnected each battery and checked the voltage. All three were at 11.9 on my volt meter and this was after two-three hours of charging at 110 amps@12.8 volts. None of the batteries was swollen showing off gassing nor were they hot. They look caved in. I went to the coach to plug it into 120 to run the fridge 3 hours after I stopped charging. The panel showed 12.1.

Three hours at 110 amps, still 11.9, 3.5 yrs old, not sure of their history, I believe your batteries are not worth having tested. Replacement at OReillys $459 each, 10 % off for veterans. They will help with install. I just replaced three of mine, I removed and reinstalled the cables. They removed and put back in place the new ones. Total cost was approx $1230.

First choice would have been MK Gel 8ds had it not been for their initial cost. For convenience, help with install, cost, I chose Oreillys. Primary reason I chose the East Penn AGMs was that I am not sure how I will be using my rv, plugged in at parks, or dry camping. In other words, no data on usage. I chose to put on an additional 670 watts bringing my system up to 1240 watts of solar instead of putting that $1350 in the batteries. I know I will use the solar, I was not so sure of the more expensive batteries. 2 LG 335 panels at $850 with freight from Ecosolar, new 100 amp/150 volt solar controller $500, plus I should get approx $350 out of my old Morningstar 40 amp mppt controller.

MK Battery Sealed Gel Battery - 12 Volt 225 Amp Hour - 8G8DLTP-DEKA

8G8D | MK Battery 12v 225 AH Deep Cycle Gel 8G8D Battery

PS Ecodirect on recent purchase of two LG solar panels, communication was perfect, they delivered on a new pallet to a local freight yard for $225. Totaly happy with their phone support that enabled shipping to a close by freight yard.

Re: House batteries low after hours on the Genset

Reply #15 – June 10, 2019, 02:49:10 am

Quote from: Jack Lewis – June 10, 2019, 02:31:16 am

Three hours at 110 amps, still 11.9, 3.5 yrs old, not sure of their history, I believe your batteries are not worth having tested. Replacement at OReillys $459 each, 10 % off for veterans. They will help with install. I just replaced three of mine, I removed and reinstalled the cables. They removed and put back in place the new ones. Total cost was approx $1230.

First choice would have been MK Gel 8ds. For convenience, help with install, cost, I chose Oreillys. MK Battery Sealed Gel Battery - 12 Volt 225 Amp Hour - 8G8DLTP-DEKA

8G8D | MK Battery 12v 225 AH Deep Cycle Gel 8G8D Battery

PS Ecodirect on recent purchase of two LG solar panels, communication was perfect, they delivered on a new pallet to a local freight yard. Totaly happy with their phone support that enabled shipping to a close by freight yard.

Jack I bought those batteries and installed them 3.5 years ago. The coach has been plugged in while in storage. And I have hardly done any boondocking. The coach was parked outside after returning from Arizona in mid March. The disconnect at the front door was off.
I suppose the batteries are toast. Thought I would get more than 3.5 yrs. out of them with the easy plugged in life they have had.
I will have to route our trip to Joseph through Pendleton (where I bought the old ones) and do the swap/core there.

Re: House batteries low after hours on the Genset

Reply #16 – June 10, 2019, 03:23:02 am

Sounds like you took good care of them. What was the float charge, I believe their spec is around 13.5? The Oreillys I just replaced were new May 2003, so they made it 6 yrs. And so 3.5 to 6 yrs, depending on use, may be the norm. That is ok for me with their ease of purchase, help installing, and not knowing how I will use my rv the next 4 years. Any time they are allowed to go below 12 or 12.2 volts drastically shortens their life. That fact, allowed me to put what I would have spent on more expensive batteries into my solar system.

I recently replaced mine when fully charged and then on a Xantrex float charge at 13.5 for weeks, when checked 9 hrs later with no draw, they were at 12.2 volts instead of in the past when they would show12.6 to 12.8, for me it was time to replace them.

As to what life to expect, it depends how deep you discharge them, how often, how long they are left in a discharged state, so a lot of variables.

Re: House batteries low after hours on the Genset

Reply #17 – June 10, 2019, 04:52:00 am

Quote from: Jack Lewis – June 10, 2019, 03:23:02 am

Sounds like you took good care of them.

Well I'm not to sure about that at this point.

I did look up a formula for the timing involved to charge a battery bank of 750 AH that shows 11.9 volts. The formula shows that my batteries are 92% discharged. (not good at all) So I have to put back 690 AH's. Even at 100 amps that would be a 7 hour charge. So it doesn't look good for my batteries. What I can't figure out is how they got 92% discharged with the battery disconnect activated. The temps were even mild during the time it sat idle. (3 months) With the AGM self discharge rate of 3% per month. I should have only lost 50-60 AH. or less than 15% discharged.

Re: House batteries low after hours on the Genset

Reply #18 – June 10, 2019, 09:56:11 am

Jacks post on the mk gels matches what Foretravel installed new. Gels typically last 10-12 years in our coaches.

The gels different chemistry can take lower charging rates than the recommended 1/5th or 1/20th of capacity with less damage.

Or running them from 50-85% SOC which was recommended by the inverter maker for a few cycles to avoid the extra gen run time needed to go from 85% to 100% charge.

The gels and agm's do need to run back to 100% as soon as convenient for a longer life.

My personal way is to replace the isolater with a auto combiner and ran a 14 amp solar panel set with a small controller to the back of the refer. The small undersized wires lose volts which turns out great for storage as they input 13.6 volts at the battery.

Most here have a much bigger solar system and a more sophisticated controller but maybe not a combiner?

Unless you run lifeline agm's the normal AGM is not equalizable. The electronic device does seem to work just takes months to restore the batteries capacity.

Oem Foretravel ran the inverter/charger and the alternator to charge at 1/5th C.

The longer life reported here shows the charger/alternator and mk gels worked well together.

I borrowed two 9 year old mk gels from my buddy used in a 4 battery install in a prevost and they tested good still.

They were the middle two on a non rotated string in the bus, the end ones were bad.

Agm's. Of course can work well if cycled perfectly and not short charged or at an incorrect rate.

Still the high line rv industry changed to gels more than 20 years ago and combiners along the way.

As far as I know all batteries can be damaged from being left in a lower SOC for long times.

The mk's have an elaborate quality control process during their building to help ensure a longer life.

Every Foretravel unicoach made had mk gels and optima spiral wound engine batteries as far as I know.

Re: House batteries low after hours on the Genset

Reply #19 – June 10, 2019, 10:01:51 am

Quote from: bigdog – June 09, 2019, 11:09:51 pm

Went out and shut everything down and isolated each house battery one at a time to check voltage. All three are at 11.9. visually all the batteries look fine. I.E. They are not bloated. If anything thing, They look like they are under a vacuum. I have read the manual and I'm not sure where to start. Batteries are 3.5 year old O'Reilly's AGM Super Starts.

I *think* your batteries have dried out. You "can" open the top of an AGM battery to add water, this is something you'd do to get yourself home in an emergency. Like if you've been out watching a Baja race on your electric start dirt bike and find your AGM battery is dead. That was motorcycle friend Pete Springer from San Diego, CA, I didn't ask where the water came from. Pete's nearly 80 and has an understanding wife.

After you replace your batteries, make sure your system is set to AGM. Those vents in the top aren't meant to be used except in extreme circumstances. Then check with a good digital voltmeter. FWIW I'd have someone check the filter caps in your charger. Excessive ripple on the DC also causes problems.

Re: House batteries low after hours on the Genset

Reply #20 – June 10, 2019, 12:01:46 pm

Quote from: Old Toolmaker – June 10, 2019, 10:01:51 am

After you replace your batteries, make sure your system is set to AGM.

The link 2000 manual says there is a setting for AGM but it doesn't come up in the set up menu F-03. When I bought these batteries I did "via the forum" set up the parameters as close as possible for AGM's.

I wonder if it might be better to just go to the old wet cell design and at least save money. As I'm not even sure what I've done wrong to ruin the AGM's in only 3.5 years of being plugged in with 1 week of boondocking last July.

Re: House batteries low after hours on the Genset

Reply #21 – June 10, 2019, 01:04:17 pm

It sounds like they were well cared for most of their life.

BUT, recently totally discharged to dead.

So, replace them (unlikely they can be brought back if they remained dead for very long, but nothing to loose by trying) AND find out why your shore power/inverter-charger did not keep them charged.

Re: House batteries low after hours on the Genset

Reply #22 – June 10, 2019, 01:24:23 pm

what inverter is in your coach?

Re: House batteries low after hours on the Genset

Reply #23 – June 10, 2019, 01:30:35 pm

Quote from: bigdog – June 10, 2019, 12:01:46 pm

I wonder if it might be better to just go to the old wet cell design and at least save money. As I'm not even sure what I've done wrong to ruin the AGM's in only 3.5 years of being plugged in with 1 week of boondocking last July.

On this end, our perspective is shaped by our educations. I'm a highly skilled toolmaker and Lynn is an electronics engineer. We're both in questionable health. So, at the age of 62 we no longer buy stuff to last forever, we buy stuff to outlast us.

That being said, in our previous rig, one used for dry camping through NH winters our DEKA battery pack only required watering twice a year. Plus for the most part even on the coldest nights we only drew the batteries down to 50% state of charge or 12.0 VDC.

Now the AGM batteries withstand vibration better, and tolerate deeper discharges without shedding plate material. But at the end of the day, they're just another re-arrangement of the deck chairs. The spiral wound AGM batteries may be the best lead acid battery design you can purchase.

You spends your money, you takes your chances, everybody is a winner!

P.S. If you're float voltage was over 13.2 I think that's what drove your battery water out the vents.

Re: House batteries low after hours on the Genset

Reply #24 – June 10, 2019, 01:34:56 pm

The F02 menu's third selection is AGM.

Your inverter is serialed numbered past 100,000 and has the ability to have a necessary battery temp management system plugged into it to alter the charging profile to the correct one for the temps the batteries are.

Simple install. Battery charging voltage could vary from 13.0 to over 14.

At 77 degrees the default 13.6 is correct. No other temp. At hot weather the default overcharges. At cold temps it undercharging.

Both lifeline and mk gels and others require a BTMS so as to not damage their batteries.

My 97's freedom 25 was before 100,000 serial number and could not have their BTMS added.

Yours can if over the 100k number

Here is the link for your 2000 manual

Xantrex | Power Inverter, Inverter Charger, Battery Charger Manufacturer(Vendor).pdf

The later inverters have not only the optional for some BTMS but also offer a BMS(battery management system) which learns your exact battery banks ability to take a charge and along with the temp system should prevent damage.

Subject to the 20% oem charging rate being used. Not as critical with gels.

Very critical with flooded cells or agm's

So a less than 20% solar system would work better with gels as they are designed to be charged at less than the 20%

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