Batteries wont hold Voltage...

[Jabroni]

You keep repeating the problem began when the auto start system was installed. Sounds to me the auto start was improperly installed?? Have you removed it?

No I have not. It's not something I feel qualified to do.

And I wanted to check with some experts or experienced people in this field before having it removed. I was hoping maybe someone had seen this issue before. Someone already mentioned that the absorb time not being set was a mistake, and indeed it was. But it's not the root issue. Otherwise I wouldve seen this problem start in the days following the auto-start install. It didnt take days of "abuse". It was instant. That day.

I cant seem to make heads or tails of the connection between the auto-start and why the batteries instantly wont hold their voltage. The installer theorized that their might be a ghost draw somewhere in the system but that is what he was supposed to be checking for yesterday and he couldnt find one.

Now granted, I understand that the resulting on/off constant BS of the auto-start was no good for the batteries as they shouldve spent longer periods in absorb. But that damaging behaviour came AFTER the symptoms were already showing. So I find it hard to put the blame on what was done December 6th thru Xmas for behaviour that started on December 6th.

[Jabroni]

Are you pulling 3000 watts, each hour, for 4-7 hours daily?

It is critical to know if this is your actual load.

Throughout the year? No.

Nov-Dec-Jan that has been the case. (note: I never intended to be out on my site for that long, there has been a lot of work to do so here I am. It drops to below 30 degrees at night)

Yes, anywhere from 2000 to 3000 watts. SOC would hit 60% or lower before the low voltage shutoff would kick in if I didnt already kick the generator back on manually to recharge the system (run the generator until the batteries were at 100% SOC). Generally I only had to run the generator 2wice in a 24 hour period.

Now? Just 1500w will kill the system in as little as 15 minutes. And again, this was IMMEDIATELY to the day that the auto-start was installed (early December). I stopped running the auto start awhile back because it was just going to break my generator running it that many times. It's taken until now to get someone out to my place to diagnose the problem.

I currently run the generator once a day to recharge the batteries and during that time is the only time I run the heaters.

[littleharbor]

You keep repeating the problem began when the auto start system was installed. Sounds to me the auto start was improperly installed?? Have you removed it?

[PNjunction]

Are you pulling 3000 watts, each hour, for 4-7 hours daily?

It is critical to know if this is your actual load.

[Jabroni]

Just for reference, these are the batteries I currently have. 8 of them.

http://www.fullriverbattery.com/product/batteries/DC400-6

[Jabroni]

A new design is needed primarily because it is NOT SAFE at 24v first of all.

Just to be *sure*, you are pulling about 3K of power for heating, each-hour for about 4-6 hours?

Here's the breakdown for maximum limits just from a safety and efficiency standpoint.

Up to 1KW = 12v
1K to 2K = 24v
2K and up = 48v system (not much 36v gear)

So if it is true that you are doing 3Kw per hour, then yep, redesign time.

Why would I need new panels and inverters? Sounds like I would just need a new battery bank. Or is my inverter/panel setup somehow tied up to 24v?

[Jabroni]

Lastly you have abused your batteries from deeply discharging them multiple times per day, compounded by parallel strings. Now have lost significant capacity. Lastly you should not be using 24 volts at this power level, 48 to 96 volts. Why are you using 3 charge controllers? That should have told you something is terrible wrong with your design.
.

why would that tell me something is wrong?

There are 3 different fail safes that can kick the generator on. What's the problem in that?

And again, Im not a expert or "fanatic" when it comes to solar. I dont know why you expect me to be. The system was running fine and handling everything I threw at it until the auto-start was added. I added the auto-start to PROTECT the batteries and instead it seems like it ruined them. But as Ive said about 3x in this thread, the low voltage was instant. The installer wasnt even to the freeway before my auto-start had to kick on. It ran for maybe 30 minutes. Then shut off, then kicked back on within no time.

I texted the installer the first day to ask if there was a problem. I noticed immediately that the geni was constantly turning on and off. Which I knew wasnt good for the generator. He wouldnt acknowledge the issue. He tried saying that even a 1700w load would kill the voltage in a few hours. Of which I remind him, we're talking a few minutes, not hours. And again, he dodges the issue every time it is brought up. He cant explain how the batteries are shot or if they even are and he certainly doesnt want to acknowledge that this issue started immediately after the auto-start was installed.

At this point Im just trying to diagnose the issue before having another company come out and fix the system.

[PNjunction]

A new design is needed primarily because it is NOT SAFE at 24v first of all.

Just to be *sure*, you are pulling about 3K of power for heating, each-hour for about 4-6 hours?

Here's the breakdown for maximum limits just from a safety and efficiency standpoint.

Up to 1KW = 12v
1K to 2K = 24v
2K and up = 48v system (not much 36v gear)

So if it is true that you are doing 3Kw per hour, then yep, redesign time.

[Jabroni]

Time for new batteries and a whole new design.

a whole new design?

Why would I need new panels or inverters?

[Jabroni]

You battery capacity at the 20 hour rate is 24 volts x 830 AH = 19.9 Kwh. If you slam them with an abusive rate of 4 hours the capacity drops by 40% or 12 Kwh. Do some simple math.

4000 watts x 4 hours = 16 Kwh and your gas tank only holds 12 Kwh. You should never discharge your batteries more than 50%, and that should not happen until 3 days with no sun shine. Whoever sold it to you did what they had to do to make a sell. They lied to you. Your batteries are shot and your system is improperly deigned and grossly undersized.

Never ever use off grid solar for any kind of heat. That is going to be a very expensive lesson you learned.

Sorry.

FYI, this isnt simple math.

Im not an electrician or a solar expert, or even novice for that matter. As Ive said, the system ran just fine until immediately after the auto-start was installed. I cannot see how one affects the other in such a short time but that's the only correlation Ive got to work from. Had this problem started a week or just a few days into running the auto start, I wouldnt be barking up this tree.

If the batteries are indeed shot, wouldnt that show up on a voltage test? I watched at the installer was measuring each battery yesterday. Each were above 6v. And when put under a load by the tester, they barely dropped to 5.9v.

[Jabroni]

Battery calcs
830 ah @ 20hr rate = 41A load is the max the batteries can sustain when brand new

2000w load for 7 hr = 83 amp drain for 7 hours = 600 ah consumed
3000w load for 5 hr = 125 amp drain for 5 hours = 625 ah consumed When you add Peukert's Law, you likely were doing 95% deep cycles

So you have hit your batteries really REALLY hard, combined with the auto-box not fully recharging, and the dealer better split the battery replacement cost with you - his fault for not configuring the Absorb time, which finished off your batteries,

wikipedia.org/wiki/Peukert's_law

Ok. This is starting to make sense somewhat.

I can tell you for certain I was never using up 95% of the batteries. They were dropped to around 50% only a few times. I generally started recharging them at 60-70%.

And yes, he did not configure the absorb time. He mentioned that "mistake" yesterday. But again, that doesnt explain the batteries falling off a cliff instantly. They went from holding their voltage to not holding their voltage immediately after the autostart was installed. Not days later.

[Jabroni]

Read out from what? The only way to determine SOC that means anything is by using a battery hydrometer to measure the Specific Gravity by sucking electrolyte out of the battery with a hydrometer. I am absolutely certain you are not doing that. Coulomb Counting will not work on lead acid batteries. That only leaves voltage.

So whicch of the three methods are you using? Only one method will work.

Yes you are abusing your batteries. They should be sized to run 2 to 3 days without need recharged on a generator. or in other words 5 day capacity of which only 3 days are usable.

Im trying to post a picture of my system's digital readout. It looks similar to this: http://www.invertersupply.com/index....33waAv1r8P8HAQ

But mine shows SOC, voltage, ADC, etc.

Now if that is not an accurate SOC and just some BS figure my system is telling me, I have no way of knowing that would be the case. Either way, it doesnt really address my issue. My system worked fine one day, the auto-start was installed, and then it didnt work as it once did. Kinda odd, no?



from the Full River website:
"Each Fullriver DC Series, Full Force and Full Throttle batteries are designed to be deeply discharged and recharged hundreds of times. With the sealed, maintenance-free aspect of all our AGM batteries, you can simply "Set it" and Forget it"."

The generator was only being used twice a day to recharge the batteries. If that is abuse, so be it. But it's nothing new to the company that installed the system. They knew what I'd be using the system for and how. All they said to worry about was the number of cycles the batteries went thru. Im not the expert here. I needed a solar system, I told the installer what I needed it to do, they designed a system that was supposed to work for that, I wrote the check. If the way Im using the batteries was destroying them (a) I wish I they wouldve told me that beforehand and (b) dont you find it just a bit odd that the batteries took a dump the day the auto-start was installed?

[Sunking]

Never thought I'd need propane heat. I put $30k into a solar system. When the installers tell me I can run up to 4000w for multiple hours on a full charge,

You battery capacity at the 20 hour rate is 24 volts x 830 AH = 19.9 Kwh. If you slam them with an abusive rate of 4 hours the capacity drops by 40% or 12 Kwh. Do some simple math.

4000 watts x 4 hours = 16 Kwh and your gas tank only holds 12 Kwh. You should never discharge your batteries more than 50%, and that should not happen until 3 days with no sun shine. Whoever sold it to you did what they had to do to make a sell. They lied to you. Your batteries are shot and your system is improperly deigned and grossly undersized.

Never ever use off grid solar for any kind of heat. That is going to be a very expensive lesson you learned.

Sorry.

[Sunking]

Time for new batteries and a whole new design.

[Jabroni]

Well, looks like the heaters are a pretty heavy load, AND the auto gen box is not allowing any absorb time.
Do you have any data of system settings [ Bulk/Absorb voltage, Absorb time, Float voltage ] from the original, pre-auto settings?
You should have an absorb time of about 2 or 3 hours in the solar, and half that for the generator (to save fuel)
The new generator settings have likely not allowed the batteries to fully charge and they have sulphated and are shot,

The Big question, is why are you not using propane heat? Generators are only 30% efficient, charging batteries 80%

I have a ton of data from the original system settings.

Ive thought maybe the batteries were sulphated. But how does that happen instantly? This issue started IMMEDIATELY the first day I had the auto-start installed. Voltage just sunk and I couldnt run the identical load I was running just the day before.

Never thought I'd need propane heat. I put $30k into a solar system. When the installers tell me I can run up to 4000w for multiple hours on a full charge, I assume the system will indeed do that. And it has just fine until the auto-start was added. What I cant seem to figure out is how the auto start would change the performance of the batteries overnight.

Furthermore, my facility isnt typically made to be lived at. It only experiences these sorts of heavy loads (at night using the batteries) every 3 to 4 months for short periods of time. The majority of the year the batteries sit in float and at night might discharge down to 92% at worst.