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Rant: EG4 48v 100ah battery has faulty BMS. Signature solar customer service is TERRIBLE

Your Jackery most likely has AC voltage clipping to reduce motor starting current peaks and not trip the inverter. You could have measured peak DC current into LV6548 inverter using clamp on ammeter with peak hold to verify that peak current is <250A. So did you keep the battery and receive $900 refund or Signature Solar kept it?
 
Brush-type motors like vacuum cleaners were noted for tripping AFCI breakers.
AC signals get rectified in analog circuits, causing an offset in reading.
Battery shunts are very low resistance, small amplitude DC signal to represent large current.
A higher frequency signal entering the system could cause an erroneous high current reading.

Have an EMI filter (rated for vacuum cleaner's current) handy? If so, try connecting in series with that. Something similar was recommended for the AFCI problem.

What I would like to do is put a small capacitor or RC filter in the battery shunt circuit. Preferably right at the IC that measures it. But that is inside your commercially assembled battery. Maybe Signature Solar could reproduce the problem with a vacuum cleaner. Even if it doesn't shut off, if current reading is erroneous they will have something to fix.

It was this sort of issue I cut my "EMI Expert" teeth on.

"Inverter specs call for higher current" isn't the issue here. Inverter starts and powers large loads. Problem is likely interference by electrical noise. That may conduct through the inverter, and a different brand might filter it better. This is an EMI susceptibility problem. Even without same inverter, SS could couple a higher frequency AC signal onto the battery cables and observe current measurement by BMS.
 
Yeah...it's disappointing for sure. The first thing I would do is put a clamp meter on the vacuum power wire (not the neutral or ground) and see what the max inrush current is. If it exceeds the battery spec, then that's your answer. The BMS may be programmed on the conservative side of what the battery pack could actually do but some of the rack mount units have an even lower max output...like the ones from watts247. I think they're only rated at 50A.

I've been trying to spec out a system that would be able to start my 4-ton HVAC unit and the number of batteries and the size of the inverter needed for that is likely a $10k purchase at least. It would be cheaper for me to install a mini-split or two and leave the main AC off.

The current inrush couldn't possibly be more than the "short circuit" value of 250amps @ ~51.2v = 12,800 watts. It's a household vacuum that a Jackery could run. It's not that big!

I don't have a clamp meter that'll show me the max inrush is. It'd be nice to have, but I know the value can't be that bad. Also, the whole setup is in Arizona and I'm in Canada for the next few months (snowbird lifestyle). So I won't be dealing with it in person for a good long while.
 
Your Jackery most likely has AC voltage clipping to reduce motor starting current peaks and not trip the inverter. You could have measured peak DC current into LV6548 inverter using clamp on ammeter with peak hold to verify that peak current is <250A. So did you keep the battery and receive $900 refund or Signature Solar kept it?

Signature solar kept the battery and gave me a partial refund.
 
Brush-type motors like vacuum cleaners were noted for tripping AFCI breakers.
AC signals get rectified in analog circuits, causing an offset in reading.
Battery shunts are very low resistance, small amplitude DC signal to represent large current.
A higher frequency signal entering the system could cause an erroneous high current reading.

Have an EMI filter (rated for vacuum cleaner's current) handy? If so, try connecting in series with that. Something similar was recommended for the AFCI problem.

What I would like to do is put a small capacitor or RC filter in the battery shunt circuit. Preferably right at the IC that measures it. But that is inside your commercially assembled battery. Maybe Signature Solar could reproduce the problem with a vacuum cleaner. Even if it doesn't shut off, if current reading is erroneous they will have something to fix.

It was this sort of issue I cut my "EMI Expert" teeth on.

"Inverter specs call for higher current" isn't the issue here. Inverter starts and powers large loads. Problem is likely interference by electrical noise. That may conduct through the inverter, and a different brand might filter it better. This is an EMI susceptibility problem. Even without same inverter, SS could couple a higher frequency AC signal onto the battery cables and observe current measurement by BMS.

I've never even heard of a EMI filter.

Oh, I'm just now remembering -- we also hooked that same vacuum up to my rig, running an Outback inverter (3600 watts) and my DIY LiFePO4 48v battery bank (with an Overkill Solar BMS), and it had no troubles. That setup (which was much more expensive than the current components) can run anything and has never given me any trouble. I'm going back to stuff that works.
 
Yeah...it's disappointing for sure. The first thing I would do is put a clamp meter on the vacuum power wire (not the neutral or ground) and see what the max inrush current is. If it exceeds the battery spec, then that's your answer. The BMS may be programmed on the conservative side of what the battery pack could actually do but some of the rack mount units have an even lower max output...like the ones from watts247. I think they're only rated at 50A.

I've been trying to spec out a system that would be able to start my 4-ton HVAC unit and the number of batteries and the size of the inverter needed for that is likely a $10k purchase at least. It would be cheaper for me to install a mini-split or two and leave the main AC off.
Not to hijack the thread, but there seem to be several soft-start solutions that work well with existing HVACs. Have you checked those out?
 
Not to hijack the thread, but there seem to be several soft-start solutions that work well with existing HVACs. Have you checked those out?

Thanks for the suggestion, and I'm sure I could modify my used vacuum to work with this delicate LV 6548 and Server-Rack 48v battery bank, but it seems like it makes more sense to just use the Jackery, since it could run it fine.

Sorry, I don't mean to be dismissive about your suggestion, I'm just still upset at EG4 and Signature Solar's lack of customer service.
 
Thanks for the suggestion, and I'm sure I could modify my used vacuum to work with this delicate LV 6548 and Server-Rack 48v battery bank, but it seems like it makes more sense to just use the Jackery, since it could run it fine.

Sorry, I don't mean to be dismissive about your suggestion, I'm just still upset at EG4 and Signature Solar's lack of customer service.
That's on me, really. I was only talking about the HVAC, not the vacuum. Thus my hijack note.

I wish I had any insight into your situation. Hedges seems quite knowledgeable though, my bet would be on their idea.

That aside.. aside.. certainly a frustrating situation, and is totally helping my stress about building my own system with EG4/MPP components.
 
I have an EasyStart 368 soft starter on my 4 ton HVAC and my 7kw generator can't start it. That got me looking into a secondary source of backup power like a LF inverter and battery solution but I just decided today to get a portable inverter air conditioner from Costco and if we lose power, my generator should be able to handle that no problem. I may still get a battery backup system, but it's lower down on my priority list now.
 
To me, it seemed like the battery just couldn't handle the sudden surge request of the vacuum. Yes, I could have added a couple more batteries, but for the needs of the application I was working with, and the fact that I wanted to test this brand of battery before buying a bunch of them, this was a pretty dismal failure.
During testing they ran a large shop vac and a tablesaw - both which have large inrush currents, but are within the specs of the battery (although pushing it) and there was no issue in starting those devices and then maintaining them after the inrush.
The EG4 battery is supposed to be able to handle 100 amp continuous output with a slight surge above that.
The battery returned tested to both of these parameters without issue.
Problem is likely interference by electrical noise.
Definitely a possibility. These batteries are designed to very precise specifications, and deviation from that may cause an issue. The rest of your comment is an accurate representation of how a poorly designed appliance can cause issues with a much higher quality battery that doesn't have a wide allowance from specs (which is how it should be, to prevent damage etc from that variance)
Maybe Signature Solar could reproduce the problem with a vacuum cleaner.
Signature Solar tried both a standard vacuum and a large shop vac without issues.
gave me a partial refund.
The refund was for 100% of the purchase price minus the cost of shipping. Their refund/return policy is extremely clear, linked here: https://signaturesolar.com/shipping-returns/

The battery operates within all the specs as listed, including the continuous amp rating, and also exceeded the runtime for loads exceeding the amperage for a minimum of the time listed in the manual. You said it yourself - the battery operated wonderfully under a number of loads and stresses, and for some reason on this single appliance was having issues. The battery exceeded all specification during testing with no errors or functionality issues.

Regarding Signature Solar's customer service: Signature Solar tech support worked with you and had numerous interactions with you over 2 days attempting to remotely diagnose the problem. They can only work with the information you provided - and they did in fact at one point try to have you use a different vacuum for testing (to which you responded that you knew it wasn't the vacuum causing the issues, and that you knew it was the battery not being able to handle a relatively small spike in power demands). We were able to show the battery operating to specs for continuous operation, as well as for the designated time periods for over current operation. It was only when we exceeded the short circuit protection amperage that we were able to duplicate the error - which is exactly how the battery is designed to operate. In my opinion, you had great customer service, and it is only the outcome you are upset with that has swayed your opinion. I don't personally believe that not getting your desired outcome is the same as receiving poor customer service.
 
During testing they ran a large shop vac and a tablesaw - both which have large inrush currents, but are within the specs of the battery (although pushing it) and there was no issue in starting those devices and then maintaining them after the inrush.

The battery returned tested to both of these parameters without issue.

Definitely a possibility. These batteries are designed to very precise specifications, and deviation from that may cause an issue. The rest of your comment is an accurate representation of how a poorly designed appliance can cause issues with a much higher quality battery that doesn't have a wide allowance from specs (which is how it should be, to prevent damage etc from that variance)

Signature Solar tried both a standard vacuum and a large shop vac without issues.

The refund was for 100% of the purchase price minus the cost of shipping. Their refund/return policy is extremely clear, linked here: https://signaturesolar.com/shipping-returns/

The battery operates within all the specs as listed, including the continuous amp rating, and also exceeded the runtime for loads exceeding the amperage for a minimum of the time listed in the manual. You said it yourself - the battery operated wonderfully under a number of loads and stresses, and for some reason on this single appliance was having issues. The battery exceeded all specification during testing with no errors or functionality issues.

Regarding Signature Solar's customer service: Signature Solar tech support worked with you and had numerous interactions with you over 2 days attempting to remotely diagnose the problem. They can only work with the information you provided - and they did in fact at one point try to have you use a different vacuum for testing (to which you responded that you knew it wasn't the vacuum causing the issues, and that you knew it was the battery not being able to handle a relatively small spike in power demands). We were able to show the battery operating to specs for continuous operation, as well as for the designated time periods for over current operation. It was only when we exceeded the short circuit protection amperage that we were able to duplicate the error - which is exactly how the battery is designed to operate. In my opinion, you had great customer service, and it is only the outcome you are upset with that has swayed your opinion. I don't personally believe that not getting your desired outcome is the same as receiving poor customer service.
Richard, one day you will learn that how the customer feels at the end of the transaction is the ultimate measure of customer service.
 
If the problem is the customer is not getting 100% of their money back (including shipping costs) when there is no reproducible issue on their end I don't think it is unreasonable for them to require customer to pay for the shipping. This seems like very common practice. When I was looking at a sol-ark I asked about who pays for shipping even if there is an issue covered by warranty and I have to pay to send back to them and they pay to send back to me. It is just going to hurt a lot more with products like this because they weigh so much along with shipping costs being higher.
 
This is my very first post on this forum, I hope this is OK. I’ve read the concerns that the customer had about the battery purchase from signature solar, I just purchased a system from signature solar, which was referred to me by a friend. I have never heard my friend, who is a business man, talk so highly about the service of any business like he has had with signature solar. They have gone over the top in spending time, lots and lots of time answering questions going over issues he had with his system, which included 5 of the EG4 48 volt 100 amp batteries.
If there’s one attitude that my friend has told me about the service from signature solar is that they really really care, they’re not in a hurry to get off the phone like so many customer service people would be, and they are very knowledgeable.
 
The refund was for 100% of the purchase price minus the cost of shipping. Their refund/return policy is extremely clear, linked here: https://signaturesolar.com/shipping-returns/

They never actually detailed how they came up with the figures they used.

My purchase price was $1,499 + $182.12 (shipping) = $1,688.12 total.

They chose to NOT refund me 100% of the purchase price because they couldn't reproduce the issue. So let's assume a 100% refund would have been $1,499. What I actually got was $939.05. That means the return shipping cost was $749.07. So to buy the battery cost $182.12 in shipping, but to return it, it cost $749.07 in shipping? Hunh?

This is part of the customer service issue. They never detailed how they came up with the numbers they were working with.

Oh, and the refund wasn't for 100% of the purchase price minus shipping. They also take 30% for restocking fees, but only in the event that they determined the battery was fine and I was at fault. That was my biggest complaint.

They can only work with the information you provided - and they did in fact at one point try to have you use a different vacuum for testing (to which you responded that you knew it wasn't the vacuum causing the issues, and that you knew it was the battery not being able to handle a relatively small spike in power demands).

And I didn't want to go out and buy another vacuum just to prove that the battery was failing when running the original vacuum.

In my opinion, you had great customer service, and it is only the outcome you are upset with that has swayed your opinion. I don't personally believe that not getting your desired outcome is the same as receiving poor customer service.

Does the battery work like it should? Maybe. Did it work for me? No.

If I had the time and tools (and was in the right location), I'd love to perform endless tests on the whole system to see exactly what happens in each part of it to determine where the fault is. If, of course, I wanted to uninstall all of the components, bench test them, and tinker with it for days on end. Then I could say, without fail, that component 'X' was the problem or caused the cascade of events to happen the way they do.

What I think happened was that the LV6548 made a huge power demand on the battery when the vacuum started up. That demand was well beyond the power requirements of the vacuum. Because the MPP LV6548 is a high frequency inverter, it just doesn't have the ability to gracefully handle surge loads without putting huge demands on the battery. That's why my old setup with a low frequency Outback inverter plus an Overkill Solar BMS on a DIY LiFePO4 bank worked so well. I'm not sure what the short-circuit rating of that Overkill BMS is, probably similar to the EG4, but because the Outback inverter can handle the surge demands so much better than the MPP, the whole system just works better.

Here's what I'd really like to see:
  1. Detailed breakdown of how customer service came up with the refund figures that they did. They never did provide that.
  2. Some kind of description or warning on the EG4 battery page detailing how modern, high-wattage, high-frequency inverters can cause HUGE inrush spikes that are well beyond the limits of a single EG4 battery.
I was working on the assumption that this new inverter would work in a way that was similar to the low-frequency inverters I was accustomed to. Sure, it had a max output of 6,000 watts, but I wasn't going to be going anywhere near that, so the 4,000+ watts that the EG4 battery could output would be more than enough for my needs for the couple of months I was going to use it in that configuration. Yes, the LV 6548 manual said it should be hooked up to 200ah of batteries, but it didn't say why. Apparently it's because of the huge inrush demands of that inverter. I just figured it was for the sustained demands of running 6,000 watts, which I wasn't trying to do.

If, for example, you were running the inverter with a 4,000 load and then turned on the vacuum, you better have a whole rack of batteries to distribute that load over!

I wish I could throw specific high-amperage loads at the EG4 battery to see how it handles spikes. If the battery is only putting out 3 amps and you throw a 90-amp surge at it, does it die? How about a 150 amp surge for 0.1 seconds? As a consumer, I don't have the equipment (in inclination) to test all of these scenarios. The math just still feels wrong to me -- how could a single appliance overwhelm a server-rack battery? It just didn't (and still doesn't) feel right. And because I can't run those tests myself, I'll never know if the battery I sent back was actually performing like it should or not. And you'll have to forgive me for not trusting the word of Signature Solar's testing team, they certainly didn't believe me that there was an issue.

Sure, I'm learning more about inrush requirements on high-frequency inverters, but I feel like that education came at a very high cost and frustration level.

For what it's worth, I'm going to go back to building my own batteries with raw cells. If a BMS is faulty, then I can ship the BMS back instead of the whole battery system. And I'm going to stick to low-frequency inverters. They just work better than the cheap high-frequency stuff.

One last note on customer service: The modern customer expects more these days. Any major big box store or online retailer will happily and readily accept product back if the customer complains. I don't often need to return things, but in this case, it was a major pain and I was left very upset. So that's my lasting impression of Signature Solar.
 
This is my very first post on this forum, I hope this is OK. I’ve read the concerns that the customer had about the battery purchase from signature solar, I just purchased a system from signature solar, which was referred to me by a friend. I have never heard my friend, who is a business man, talk so highly about the service of any business like he has had with signature solar. They have gone over the top in spending time, lots and lots of time answering questions going over issues he had with his system, which included 5 of the EG4 48 volt 100 amp batteries.
If there’s one attitude that my friend has told me about the service from signature solar is that they really really care, they’re not in a hurry to get off the phone like so many customer service people would be, and they are very knowledgeable.

Sure, a sales guy will always spend a bunch of time with you to get you to buy things. It's the after-sale customer service that I'm having issues with.
 
Sure, a sales guy will always spend a bunch of time with you to get you to buy things. It's the after-sale customer service that I'm having issues with.
I completely understand what you mean by that, but this situation with my friend has been after his purchase that he’s been receiving all the help. He is not one to go overboard on complementing anybody, so it’s been so surprising that he has been excitement on steroids about signature solar and all the help that he’s been receiving from them after the sale.
He bought a new Nissan Leaf that he’s been charging with the Signature Solar system, and has needed lots and lots of help and advice with that.
I don’t mean to discount your experience with them, because it seems to be very real, But my friends experience has been, and is the complete opposite of what your experience was.
 
Here's what I'd really like to see:
  1. Detailed breakdown of how customer service came up with the refund figures that they did. They never did provide that.
  2. Some kind of description or warning on the EG4 battery page detailing how modern, high-wattage, high-frequency inverters can cause HUGE inrush spikes that are well beyond the limits of a single EG4 battery.
I'll get this for you tomorrow. Typically restocking is charged depending on the condition. We can't re-sell the battery as new if it has cycles on it, cosmetic blemishes, etc. For opened items that were never used, Signature Solar rarely charges restocking. In fact, they likely still have the unit on site and I'll personally go look at it to see what condition it is in to address this. Just to put this out there because people may read that last sentence the wrong way - Signature Solar NEVER sells used products as new, regardless of cosmetic appearance. However, their 'garage sale' items vary in price on a number of factors, and that's where the 'restocking fee' comes into play.
 
I've never even heard of a EMI filter.

Oh, I'm just now remembering -- we also hooked that same vacuum up to my rig, running an Outback inverter (3600 watts) and my DIY LiFePO4 48v battery bank (with an Overkill Solar BMS), and it had no troubles. That setup (which was much more expensive than the current components) can run anything and has never given me any trouble. I'm going back to stuff that works.
250 A is an incredibly short trip point
We said 5000w per battery. Most people build solar systems with healthy discharge rate ratios under .5C max but ours handles 1C

You seem to be looking for a 2C ratio bms that is more like an EV battery, we don’t reach those apps as indicated by our specs.

If you used a 3000w inverter you could run your vacuum, but with the 6548 platform you are undermining the unit.
 
Sorry op. Not really feeling this one. Sounds like the buyer goofed. And now wants to tell the internet how he got screwed.

And this coming from someone who sorta enjoys dumping in sig solar for the battery/inverter fubar deal.
Can confirm: Bluedog225 likes dumping on me /s
@Bluedog225 you are typically pretty fair in your criticisms.
 
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