I messed up: Need advice on bringing Trojan L16s back from near dead

[hammick]

As long as your charge controller does not power down at ~ 8VDC, it should recover. you might have to instruct your neighbor to short the PV input, to the Battery, to get some charge into the batteries for a couple minutes for the controller to get enough voltage to boot and continue. Hopefuly you have hard programmed the controller for a fixed battery voltage, and not auto-detect.

Thanks Mike. The battery voltage operating range from the MPPT 60 150 data sheet is 0vdc to 80vdc. But it sounds like you are saying it needs 8vdc to power on. My inverter should go to standby when the batteries hit 44 volts and then shut down completely after 24 hours.

I have shut down my CC on several occasions and it always keeps it's settings when powering up. I'm pretty sure I programmed it for 48v and not auto-detect but not positive.

By "recover" I assume you mean that the CC will start charging. Not that I haven't damaged my battery string.

[hammick]

What loads are on at your cabin right now? Is a frig running? Security lights? I'd expect your inverter to use about 1000wh a day just being on, so if that's the only thing, your batteries might go a 4-5 days before dropping to <50%. It might not be a bad as you think. Being in a similar situation, I just shut the inverter off during the deepest part of winter when I'm not there

Sorry I should have mentioned I'm already in deep trouble. They are currently at 33% SOC according to my Trimetric shunt based meter (I have a Blink camera pointing at the meter). I have no way to monitor anything other than SOC or control anything.

My loads are very light which I believe is why the inverter hasn't shut off yet. So that means the batteries are not at 44 volts yet which is the default LBCO of my inverter. I'm kicking myself for not setting the LBCO to the high setting of 48v. I have the ability turn on seven lights but they are all LED bulbs and not drawing enough power to trip the LBCO.

Loads are a Hughesnet router, mesh wifi, Insteon HUB, Blink camera HUB, two blink cameras plugged into 5v phone chargers, weatherstation display, WIFI thermostat for my gas stove and seven insteon light switches. All other loads are turned off. I'm using about 9% of my batteries each night. Quite a bit more than 9% when I don't charge at all. I think I Wednesday I put 10% back and charged up to 63% SOC. Then the blizzards hit and it's been all downhill. I believe the last time I was at 100% SOC was last Friday or Saturday.
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This is the first time I have ever left the inverter on when I'm not there. I'm kicking myself for not waiting until I had my generator auto start all set to go.

Slight chance a guy might get up there tomorrow and clear my panels. Full sun forecast for Sunday.

I'm debating driving up on Monday so I can start the long process of equalizing and taking SG readings.

If the panels clear and they charge so my meter shows 100% I'm wondering if waiting a month to equalized will make any difference. I suspect the damage has already been done.

[Mike90250]

As long as your charge controller does not power down at ~ 8VDC, it should recover. you might have to instruct your neighbor to short the PV input, to the Battery, to get some charge into the batteries for a couple minutes for the controller to get enough voltage to boot and continue. Hopefuly you have hard programmed the controller for a fixed battery voltage, and not auto-detect.

[MichaelK!]

What loads are on at your cabin right now? Is a frig running? Security lights? I'd expect your inverter to use about 1000wh a day just being on, so if that's the only thing, your batteries might go a 4-5 days before dropping to <50%. It might not be a bad as you think. Being in a similar situation, I just shut the inverter off during the deepest part of winter when I'm not there

[hammick]

Well the perfect storm of weather, bad luck and my mistakes may have trashed my 4 1/2 year old Trojan L16RE-A batteries at our off grid vacation place in Montana. I'm 1,200 miles away and couldn't get up to our place even if I was close. Snow is deep and my panels are covered. The earliest I see getting any charging from my CC is two days from now and that's assuming the snow melts off my panels. The most they are going to get this time of year from my 2.6kw array is 30 amps for a couple hours. The closest neighbors were going to clear the snow off my panels for me but they are snowed in. Even their tracked Polaris Ranger is stuck.

I'm not scheduled to be at our place until March 8th. I could drive up there as early as Sunday but fear it won't make any difference whether I get them charged and equalized five days from now or a month from now. I'm assuming they are already trashed. I'm really upset about this.

My only real hope is that the Trojan "Smart Carbon" paste in my batteries actually makes a real difference with partial state of charge. Good chance it's just marketing gimmicks though.

Looking to hear from you off grid guys who have gone through something similar and your outcome (good or bad). I'm really upset about this so please no Sunking type BS. I know I made mistakes and will learn from them. Just hoping to salvage my $3,000 battery bank. I have two good hydrometers and I know how to use them.

Equipment listed below as well as stand alone chargers I have. My inverter is capable of charging at 110 amps.

Thanks.

Trojan L16RE-A 325ah (one string of eight)
Conext XW5548 inverter
Conext MPPT 60 150 CC
Conext Combox
Conext SCP
Conext Battery Monitor
Bogart Trimetric Battery Monitor

MEP-802A diesel 5kw genset
Yamaha 1600 inverter genset
25a manual 12v charger
10a manual 6v/12v charger
Lester Summit II 1050 48v charger