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Location
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Do any of you know much about solar/battery setups?
I have a fully off-the-grid setup at my rural property.
- 6k watts worth of solar panels
- 4k watts magnum inverter & controller
- a 24v battery bank of "Full River AGM" batteries that equate to 830 amp hours of storage
- and a Honda 7k generator
Ive had the system for about 9 months.
During the spring/summer months the batteries do not get used much at all. During the winter it wouldnt be much different but Im spending a lot of time up at my place doing maintenance on the property so Im running heaters in the living quarters of the shop I built.
Here is the situation/problem...
I normally would run about 2000-3000 watts worth of equipment (heaters mostly). I could get 5-7 hours out of my battery storage during the day before needing to turn the generator on to recharge the system. At night, from a full charge at midnight, I could get about 5 hours out of the system before the low voltage would kick the system into protection mode and shut everything down. It'd be at that point I'd have to get up and go turn the generator on (about 5 in the morning).
That started to suck. So I had my solar company install a generator auto-start so the generator would kick in once the system reached a low "state of charge" and charge the system back up from 5am to however long it took, and then by 10am the natural sunlight could take over from there.
The concept was to go from having to manually run the generator twice a day (9pm-midnight & 5am-9am) to instead the auto start kicking on and all I need to do is make sure the generator is topped off with fuel.
Here's where the problems started... Immediately after the auto-start was installed, I can no longer get the 5+ hours of usage out of my batteries with a 3000w load. It takes about 15 minutes for the voltage to sink to unsafe levels so the auto-start kicks on to protect the batteries. The geni runs for 20 minutes or so, bringing the voltage back up to a healthy level and then the generator shuts down. 15 minutes later the cycle repeats itself.
I lowered the load to 1500w to see if that would preserve the voltage. No dice. It maybe bought me an extra 2 minutes before the voltage hit it's minimum level again.
It doesnt matter if I start from a fully 100% charged battery bank. The state of charge might only drop to 97% before the voltage is so low that the geni auto-start kicks on. So I tried turning off the auto-start. The system then shuts down at 23volts as predicted. Reminder, before the auto-start was installed, I could run my batteries all the way down to as low as 45% state of charge before the low voltage protection kicked in and shut the system down. Now? The state of charge is barely used at all as the system simply bounces between low & ample voltage.
I use software to track my solar system's setup and at one point, at it's worst, the generator had kicked on 40 times in one day!!!
I called my solar company that has done all my installs, they instantly tried blaming the batteries and said that the batteries have gone bad/run their life cycle. Because Ive apparently cycled my batteries too much.
My batteries are less than a year old. Due to my software, I can track the number of cycles. The batteries have maybe been cycled 200 times at most. They are rated to get at worst 1000 cycles how I use the system.
But again, everything ran just fine BEFORE the auto-start was installed. I find it HIGHLY UNLIKELY that my battery bank just took a shit the day after the auto-start was installed.
So after much fighting with the solar installers, they sent their guy out to diagnose the system. He said that a short in the system could be drawing the voltage down faster than normal. He went thru the system, found no short. He checked the voltage of all 8 batteries, none were "bad" per se. He then proceeded to do the math (for the 30th time) for me on what my battery bank is made to handle and that Im asking too much of it. He said that at my load, I should only get about 4 hours of use out of it before the state of charge/voltage is too low and the auto-start kicks on. This is where I start to get super frustrated because it's like he's not listening or acknowledging the issue at hand.... IF I COULD GET 4 HOURS OUT OF MY BATTERIES ON A 3300w LOAD, I WOULDNT BE CALLING HIS COMPANY WITH ANY ISSUES. Im only getting about 15 minutes before the voltage drops too low. This is a new problem, that only started AFTER the geni auto-start was installed.
I have no idea how the auto-start could be causing the problem. Im not well enough versed in solar or electrical to diagnose the problem myself. All I can do is point out the symptoms and hope the "experts" can fix it.
At the end, he handed me a estimate for $5000 to have my batteries replaced. With the batteries he recommends for my setup. Mind you, I bought this system FROM HIS COMPANY. He said I'd need to replace the current batteries so the old ones could be sent in to the mfg for warranty inspection and then I'd be given a fraction of what I paid as a refund. So in the end it'd be a net loss as I'd have to spend MORE money on new batteries, installed by the same fucktards that caused this problem in the first place. I will NOT be giving them any more of my business. But I need to diagnose this battery voltage issue in the meantime.
Any thoughts?
I have a fully off-the-grid setup at my rural property.
- 6k watts worth of solar panels
- 4k watts magnum inverter & controller
- a 24v battery bank of "Full River AGM" batteries that equate to 830 amp hours of storage
- and a Honda 7k generator
Ive had the system for about 9 months.
During the spring/summer months the batteries do not get used much at all. During the winter it wouldnt be much different but Im spending a lot of time up at my place doing maintenance on the property so Im running heaters in the living quarters of the shop I built.
Here is the situation/problem...
I normally would run about 2000-3000 watts worth of equipment (heaters mostly). I could get 5-7 hours out of my battery storage during the day before needing to turn the generator on to recharge the system. At night, from a full charge at midnight, I could get about 5 hours out of the system before the low voltage would kick the system into protection mode and shut everything down. It'd be at that point I'd have to get up and go turn the generator on (about 5 in the morning).
That started to suck. So I had my solar company install a generator auto-start so the generator would kick in once the system reached a low "state of charge" and charge the system back up from 5am to however long it took, and then by 10am the natural sunlight could take over from there.
The concept was to go from having to manually run the generator twice a day (9pm-midnight & 5am-9am) to instead the auto start kicking on and all I need to do is make sure the generator is topped off with fuel.
Here's where the problems started... Immediately after the auto-start was installed, I can no longer get the 5+ hours of usage out of my batteries with a 3000w load. It takes about 15 minutes for the voltage to sink to unsafe levels so the auto-start kicks on to protect the batteries. The geni runs for 20 minutes or so, bringing the voltage back up to a healthy level and then the generator shuts down. 15 minutes later the cycle repeats itself.
I lowered the load to 1500w to see if that would preserve the voltage. No dice. It maybe bought me an extra 2 minutes before the voltage hit it's minimum level again.
It doesnt matter if I start from a fully 100% charged battery bank. The state of charge might only drop to 97% before the voltage is so low that the geni auto-start kicks on. So I tried turning off the auto-start. The system then shuts down at 23volts as predicted. Reminder, before the auto-start was installed, I could run my batteries all the way down to as low as 45% state of charge before the low voltage protection kicked in and shut the system down. Now? The state of charge is barely used at all as the system simply bounces between low & ample voltage.
I use software to track my solar system's setup and at one point, at it's worst, the generator had kicked on 40 times in one day!!!
I called my solar company that has done all my installs, they instantly tried blaming the batteries and said that the batteries have gone bad/run their life cycle. Because Ive apparently cycled my batteries too much.
My batteries are less than a year old. Due to my software, I can track the number of cycles. The batteries have maybe been cycled 200 times at most. They are rated to get at worst 1000 cycles how I use the system.
But again, everything ran just fine BEFORE the auto-start was installed. I find it HIGHLY UNLIKELY that my battery bank just took a shit the day after the auto-start was installed.
So after much fighting with the solar installers, they sent their guy out to diagnose the system. He said that a short in the system could be drawing the voltage down faster than normal. He went thru the system, found no short. He checked the voltage of all 8 batteries, none were "bad" per se. He then proceeded to do the math (for the 30th time) for me on what my battery bank is made to handle and that Im asking too much of it. He said that at my load, I should only get about 4 hours of use out of it before the state of charge/voltage is too low and the auto-start kicks on. This is where I start to get super frustrated because it's like he's not listening or acknowledging the issue at hand.... IF I COULD GET 4 HOURS OUT OF MY BATTERIES ON A 3300w LOAD, I WOULDNT BE CALLING HIS COMPANY WITH ANY ISSUES. Im only getting about 15 minutes before the voltage drops too low. This is a new problem, that only started AFTER the geni auto-start was installed.
I have no idea how the auto-start could be causing the problem. Im not well enough versed in solar or electrical to diagnose the problem myself. All I can do is point out the symptoms and hope the "experts" can fix it.
At the end, he handed me a estimate for $5000 to have my batteries replaced. With the batteries he recommends for my setup. Mind you, I bought this system FROM HIS COMPANY. He said I'd need to replace the current batteries so the old ones could be sent in to the mfg for warranty inspection and then I'd be given a fraction of what I paid as a refund. So in the end it'd be a net loss as I'd have to spend MORE money on new batteries, installed by the same fucktards that caused this problem in the first place. I will NOT be giving them any more of my business. But I need to diagnose this battery voltage issue in the meantime.
Any thoughts?
Is it possible that something on the auto start is drawing enough current to drain your system faster? Seems unlikely but there is something to the auto start that is your problem. Not the system you have IMO. I'm not an electrician by any stretch.
Seems like the generator is not getting an accurate reading of where you're system's charge is actually at. It's like it's reading that it's low but it really isn't maybe. My reading comprehension is pretty low right now.
When turning the auto-start OFF, I cannot get the same performance as before.
Im not a electrician either. Or a solar expert. But like you I do have common sense and can problem solve. It's clear something changed when the auto-start was installed. What that is? I have no idea and the company that installed it is little help.
They further reinforce my lack of confidence in their diagnosis when they are so quick to dismiss that the auto-start could be the problem. They are avoiding it at all costs.
To answer your question tho, I asked several times if there is something that could be affected by the auto-start and he repeatedly said no. My inverter's controller has a digital read on the current voltage draw of the system. There doesnt appear to be any unknown "ghost" draws. But then again, Im diagnosing this alongside the same idiot that created the problem so Im not sure if he'd see the problem if it was staring at him in the face.
I have NOT removed it entirely. I can turn the function OFF from the controller.
I cannot get the charge to drop to 80% much less 45% with a decent load on the system. It might drop about 3-4 points before the voltage has dropped to a unsafe level and then the auto-start kicks on or if it's disabled the system goes into protection and shuts down. Mind you, I'd never had a low voltage shutoff EVER occur with this system in the 9 months Ive had it unless I had a ridiculous load on it (at night) that drew power too fast or I'd dropped the state of charge to around the 50% mark. A low voltage shutoff at 95% state of charge is unheard of in my experience with this system.
Now if I just have a couple hundred watts on the system? Then I can get the state of charge to drop to lower levels such as 80% or lower. But that's only with the slow draw. If I put a load of 1000w or more on it then the voltage just tanks.
The Shop
What setting options do you have on your controller? Can you tell it to kick on at a certain amp hour or wattage reading? It seems like there is either a setting that isn't being picked up.
I have 4200 watts of solar, but it is grid tied. It cut my power bill by 60%. In the end, that much power cost me about ten grand as I got a huge tax break from the Feds. The state mostly paid for my solar hot water as well.
If I had to do it all over again, I would just spend the $5000 for a GENERAC system. Shortly, I will be building a new house. That house will have a GENERAC. Yes, it is fuel dependent, but in my opinion, solar is just not enough unless you're willing to go dark for a bit during rainy days (of which we have a lot in Florida) or periods of no power (hurricanes in Florida). Plus, I store a lot of fuel now and have never had any problems doing so. PRI-G is worth every penny.
Overall though, solar has saved me a lot on my power bill. If I lived here a few more years, it would pay for itself.
I know I'm not much help. Please keep me informed of what you discover.
Here are my settings options and what I have had them set too:
Auto-Start on State of Charge: originally set to 60% and to shut off at 85% (assuming the panels could do the rest)
Auto-Start on Voltage: originally set to 23.8v and to shut off at 28.8
Auto-Start on Load: originally set to 3600w or 30amps
Ive got the SOC to auto-start currently at 80% and shut off at 95% as to protect the batteries. But again, this function doesnt ever see use. The voltage drops way too fast.
I lowered the Voltage auto-start to 23.2 and have tried it as low as 23 to see if when under load, the system would hover in the low 23's. It doesnt. I just continues to drop.
And I never put a 3600w load on the system so that function has never had to kick in.
Typically in the past, the voltage would correlate with the SOC. Now? They dont correlate at all.
I agree, if I could do it over I would go propane. Then again, I built this compound to be my zombie apocalypse bunker. So I didnt want to become too fuel dependent. The irony is Im now going thru gasoline at an insane rate. Go figure.
Im going to talk to another solar company local to me. Ive heard they've had to do a lot of "clean up" work on the jobs my installer has done in the past. If they can definitively tell me it's the auto-start then I'll be quick to have that removed.
https://www.solarpaneltalk.com/forum/off-grid-solar/batteries-energy-st…
Nobody there can really draw the correlation between the auto-start and the batteries not holding their voltage under load. They just keep telling me the same thing, that the batteries are fucked or that Ive abused them.
That sure is some coincidence that to the day the auto-start was installed, the batteries all of a sudden nose-dived.
According to that forum's resident dickhead know-it-all, the SOC readings that my controller puts out are not true SOC readings. They are actually correlated estimations based on the SOC. He claims that they use this chart:
If that is the case, then my SOC should be dropping as fast as my voltage does, which it doesn't. Which means that I could possibly be getting either false voltage or false SOC readings.
Im not convinced my batteries are fucked, as when put up to a volt meter they show enough health to not demand replacement.
If the controller thinks the voltage is much lower than it is, then it's going to kick on the generator or shut down my system (depending on if the auto-start is turned on or not). Im guessing that something got changed by the installer during the auto-start (or the auto-start itself is causing it) to cause false voltage readings. Thus the reason the SOC needle isnt moving much.
Just a half-witted theory. Im grasping at straws. The solar company Im dealing with wont acknowledge the issue and the guys on the solar forum havent been much help either. Everyone just wants to immediately say the batteries are fucked and theyve been fucked and Im only now just noticing. Which is impossible.
But that was the case in November before the auto-start was installed.
I gotta remove the auto-start. The problem is, I dont know what settings on the controller were changed so I dont know if removing the auto-start is going to "put things back to the way they were".
This article does a great job explaining it.
EV Batteries in Winter
I just called Magnum Energy (the mfg of all my inverter/charger/controller components). Y'all are gonna love this...
I spent 2 hours with their customer support. I wanted to understand the auto-start better and what could be the issue.
We went thru every setting on the controller and also some of the solar charging hardware.
(1) other than the kind folks on this forum, they were the first person Ive spoken too to NOT dismiss my claims of the system not performing immediately after the auto-start was installed. They were very perplexed at the coincidence of it all.
(2) that said, they could not fathom how the auto start would have any effect on voltage readings.
(3) so then this is when it got "fun". We went thru all the settings on the controller and here are the mistakes found (some of which you already alluded too...
- AGS stop was set to 28.8 (shouldve been set to FLOAT)
- Absorb was only set to 2.0 hours (shouldve been to 4.0 hours)
- and here's the REALLY big one, the BMK was set to 790aHrs (so the controller this entire time has been charging for a smaller battery bank than was already here and for too short a absorb time... my actual battery storage is 830aHrs)
- and lastly, the jumpers on the solar charger controllers were set wrong, and were set for a much smaller solar array than I currently have
So yes, the batteries have been taking a beating. During the summer due to the jumper settings and since November when the generator was being used heavily since the absorb as set wrong. And apparently the entire time since the BMK has been wrong all along. Magnum had some settings and charging advice that they thought could try to salvage the batteries a bit but cleaning off the plates (forced charging) and so Im going to try it.
This is mostly a installer setup error, and the resulting damage to the batteries not being charged fully.
That said, Im still hung up on the coincidence of it all. The performance drop off was too sudden and was immediate after the auto start was installed. There just seems to be something else too it. Im not saying the batteries havent taken a hit. But if there is a problem related to the autostart, new batteries arent going to solve this issue.
I don't know what your temperatures are but at 0 degrees you have 60% capacity.
It's good you may be getting closer to a resolution. I will say it's usually not recommended to charge batteries to 100%. Tesla actually recommend's you only charge to 80% unless you need the last 20% for trips. It is so important to them they have software built in to stop charging at a user defined percentage.
Pit Row
Could the coincidence of the batteries not holding voltage be possibly due to the cold? I suppose that it is possible. I did go over the temps with the Magnum tech support and they werent alarmed by any of what Im experiencing on that front.
They did say that the batteries were supposed to get 100% charged and then the geni should stay on a additional 4-6 hours for optimal battery life. That is only possible when the sun is out, not during winter months.
I wouldnt say Im any closer to a resolution. It looks like Im not gonna be in a fight with the solar company that set up my controllers to see if they will take responsibility for the damage done to the batteries. And again, Im not convinced new batteries will fix this issue that mightve been caused by the geni auto-start.
Installer is blaming the batteries
Hardware mfg is blaming the installer
If I call the battery mfg they will no doubt blame the installer
Nobody thinks the auto-start is the issue. "It's all just one big coincidence". I still think there might be a lose wire somewhere that is the root issue of my current problems.
I'm building a house starting next month and plan to do a solar only setup at this point. I've lurked on there for a few years but never posted because I still don't feel educated enough to carry on a conversation at this point with them. What was the verdict on the output your panels are producing?
And they speak over the average person's head to a fault. Then again, maybe that's how it sounds when a noob comes to a MX forum that knows zilch about dirtbikes.
Part of me wishes I'd gone to that site for setup advice in the beginning, but part of me doesnt. I feel I woulda got bashed for asking the metaphorical "which 450f is best for me?" question. They certainly dont seem too interested in helping a noob out. I posted my situation to a few different forums and wasnt met with nearly the attitude. Other sites have tried to help but we're still coming up empty. I made my most progress when I got on the phone with Magnum today. But even they cannot draw from the auto-start correlation, nor do I think they want too, it's their product.
EVERYONE wants to blame the batteries. And Im sure if I got on the phone with the battery company, they'd be blaming the installer or the Magnum controllers. It's one big circle jerk.
The verdict on my panel output? Nobody on that other forum challenged me when I brought up the fact that I can run 3000w loads on a summer day without any battery usage. Meaning, the panels keep up with the load easily. I have no idea why they were so fixated on that anyways. It just felt weird, they were really trying hard to prove that my system didnt work and that I was ripped off horribly. Ultimately, the tech I spent 2 hours on the phone with went over my entire system with me, including the panel array. She was extremely knowledgable on everything and that is how we discovered that the solar charger jumpers werent set correctly. If my panels were only putting out 1440w like the troll was suggesting, she wouldve said as much, but she didnt. She confirmed my system worked as intended.
I think a lot of conclusions were instantly drawn and then those guys ran with them, rather than ask more questions as to better ascertain the situation. Im a noob on this topic so it's only natural that Im not going to explain everything right. I might list the color of my power band or the weight of my piston return spring from time to time.
http://forum.solar-electric.com/discussion/351556/batteries-abruptly-st…
Much better community. They'll be way more helpful.
And I think you're right about the temperature.... here are some stats:
Most of November - avg battery temp was 20 degrees C
November 26th thru early December - avg battery temp dropped to 12 degrees C
Early December to now - avg bater temp dropped again to 10 degrees C
There is the smoking gun that explains the "coincidence".
Thank you. Who should I have come out to double check this? An electrician or a solar guy?
The installer (a) had his mind made up that it's the batteries before even coming out to check his work (b) stopped responding to my texts or emails and (c) Im pretty sick of dealing with his incompetent ass at this point.
And yeah, that one guy was letting you have it. But he was definitely knowledgeable. Just too bad he was such an ass about it.
What do people think about Tesla solar shingles/battery combo?
https://youtu.be/dRqSkR4ENAg
As for the guy who took a liking to me? Turns out he's not as knowledgable as he thinks he is. He's got a rep among the solar forums as being a asshat everywhere he goes. At this point, Im done trying to get help on that first site. This one has been much better:
http://forum.solar-electric.com/discussion/351556/batteries-abruptly-st…
Lots to read there and learn. At least for me. Easier to digest.
I'll definitely let everyone know the end result. I really think that in the end we're gonna see that tcannon521 was correct and it was the sudden temp drop off. Tho it wouldnt surprise me to find out that the AGS was wired wrong the way 3D suggested. And I guess the silver lining is that by having to call the Magnum techs, I was able to fix so many settings that were damaging my batteries.
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