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

BentleyJ

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Jan 13, 2022
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Riverside County, CA
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.
Take a look at Hyper Engineering Soft starters, they can reduce inrush by 70%. We have a 4 ton Goodman with a model SS1B08-16SN (230V, 60/50Hz, 08-16 FLA) installed. Our Schneider Conext XW+ 6848 starts and runs the A/C with no problem.
 

SignatureSolarJames

Make DIY Solar Great Again
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Jun 26, 2020
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168
Why didn't your "tech" team advise him of this prior him sending the battery back and losing hundreds of dollars? Seems his disappointment could have been easily avoided.
Agreed. We had a convo off of this about sticking with the numbers instead of letting customer emotions take over all 100% of the call.
Our tech gang are some of the best kinds of people and they really get put through a lot being there for everyone’s projects all day.
 

SignatureSolarJames

Make DIY Solar Great Again
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Jun 26, 2020
Messages
168
Take a look at Hyper Engineering Soft starters, they can reduce inrush by 70%. We have a 4 ton Goodman with a model SS1B08-16SN (230V, 60/50Hz, 08-16 FLA) installed. Our Schneider Conext XW+ 6848 starts and runs the A/C with no problem.
I’ve used these since 2015! Outback, Schneider, sigineer and of course growatt
Very good units
 

Hedges

I See Electromagnetic Fields!
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Mar 28, 2020
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11,034
Alternate theory (besides high frequency noise causing error in battery current measurement) is high-frequency inverter draws poorly filtered (or unfiltered) pulses from battery. If delivering 6kW to start the motor but drawing pulses on 50% of the time, off 50% of the time, those pulses could be 12kW. Higher at the peak of the sine wave.

How fast is the BMS? Does it allow brief overload or trip immediately?
 

AntronX

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Oct 24, 2021
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103
MPP Solar LV6548 inverter may be capable of peak current draw above 250A. It can do 13kW surge. To supply 13kWac surge it should require around 15kWdc from battery due to inverter conversion loss of about 15% at that power level. 100Ah LFP cells have about 1mOhm internal resistance, so trying to draw lets say 300A will sag the voltage by 0.3V per cell or 4.8V for 16S pack. So your fully charged battery sitting at 52.8V will sag to 48V plus another 2 - 3 volts drop from the MOSFETs in the BMS. Add in voltage drop the wires, fuses, breakers and connectors and your inverter may only see 40V at 300A = 12 kW DC which is still below 15 kW it should be able to draw. At 15 kWdc and 40V it could try to pull 375A to satisfy that 13kWac surge rating. I looked at the manual for LV6548 and there is no mention of max current on DC side it can request during a surge event. So good chance your inverter is too powerful for this battery BMS and surge power events could be reaching well above 250A short circuit trip level of EG4 battery BMS board.
 

AntronX

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Oct 24, 2021
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Another compounding issue could be the 60 Hz AC ripple pass through to the DC input side during surge event due to DC side electrolytic capacitors not having enough capacity to completely carry peak current of each surge AC waveform cycle. So there may be additional 60 Hz AC current peaks on DC side on top of RMS current needed to make 13kWac output and your DC input could be seeing as high as 525A current peaks coinciding with AC waveform peaks.
 

robby

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May 1, 2021
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While I do believe the OP had less battery power than would be ideal I also think the EG4 has some issues with tripping to easily when loaded down. This is certainly not the first post where a user has had overload issue and yet another battery pack worked perfectly. I also remember a thread where a few guys just changed out the BMS in the EG4 to a different brand and the problem was solved.

What would be nice is to hear of a warranty issues being solved by Signature Solar that did not involve pages of Drama and an unhappy customer. Personally I think this whole "It works for us so your out of luck" warranty policy absolutely sucks. Maybe I missed the post where someone sent back something to SS and they actually said it did not work and just refunded them or replaced the item.
 

AntronX

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Oct 24, 2021
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103
It may be that BMS inside EG4 battery is working as designed where current draw above 250A gets quickly tripped in order to protect the MOSFETs inside the BMS and not have it blow up during a real short circuit fault. Those other BMS boards may not have short circuit protection that actually works to make sure BMS does not self destruct.
 

houseofancients

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Nov 29, 2019
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While I do believe the OP had less battery power than would be ideal I also think the EG4 has some issues with tripping to easily when loaded down. This is certainly not the first post where a user has had overload issue and yet another battery pack worked perfectly. I also remember a thread where a few guys just changed out the BMS in the EG4 to a different brand and the problem was solved.

What would be nice is to hear of a warranty issues being solved by Signature Solar that did not involve pages of Drama and an unhappy customer. Personally I think this whole "It works for us so your out of luck" warranty policy absolutely sucks. Maybe I missed the post where someone sent back something to SS and they actually said it did not work and just refunded them or replaced the item.
well, don't agree here.
the battery does what i needs to do and what has been agreed to when purchased.
the OP failed to read up on the minimum requirements of their own inverter.

why would ss be responsible here ?
if it were my company i would have told the customer :

RTFM and we'll return the battery to you, you will need an extra one to be up to the minimum spec.

i find it almost amusing that the general consensus here seems to be : i f**cked up, but ss is responsible
 

AKvalleyguy

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Nov 21, 2021
Messages
93
Sorry op. Not really feeling this one. Sounds like the buyer goofed. And now wants to tell the internet how he got screwed.
Yep
well, don't agree here.
the battery does what i needs to do and what has been agreed to when purchased.
the OP failed to read up on the minimum requirements of their own inverter.
And Yep. I tend to shoot from the hip and bend rules but the key is understanding and being okay with the consequences.

This does look like a cut and dried underpower situation. Now, if a second battery was added and it didn't work, different story. Oh man, I feel like Judge Judy or something. Give me a gavel :LOL:
 
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ThomasSun

New Member
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May 25, 2022
Messages
11
The EG4 battery is supposed to be able to handle 100 amp continuous output with a slight surge above that. 100 amps at around 51.2v = 5,100 watts. Yet somehow running a household vacuum caused it to go into short circuit protection (which is only supposed to kick in at 250 amps).

The battery could handle large loads, it just couldn't handle the surge. A Jackery could. I expected more from a professional-grade server-rack battery.
According our experience, maybe Jackery battery don't have the short protection and this is why it can run your household vacuum.
 

robby

Photon Vampire
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May 1, 2021
Messages
1,810
well, don't agree here.
the battery does what i needs to do and what has been agreed to when purchased.
the OP failed to read up on the minimum requirements of their own inverter.

why would ss be responsible here ?
if it were my company i would have told the customer :

RTFM and we'll return the battery to you, you will need an extra one to be up to the minimum spec.

i find it almost amusing that the general consensus here seems to be : i f**cked up, but ss is responsible
The problem is not responsibility, the problem is coming to a solution that is open and fair.
I just don’t see a customer losing $700+ and having nothing to show for it as a fair outcome!
Companies I have worked for would have either offered equitable solutions or met the customer half way on the return shipping. We don’t want to lose customers because we know one pissed of customer can cost you ten more sales down the road.
On the extreme end of things Amazon pays shipping both ways without the customer ever being doubted.
 
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houseofancients

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Nov 29, 2019
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1,136
The problem is not responsibility, the problem is coming to a solution that is open and fair.
I just don’t see a customer losing $700+ and having nothing to show for it as a fair outcome!
Companies I have worked for would have either offered equitable solutions or met the customer half way on the return shipping. We don’t want to lose customers because we know one pissed of customer can cost you ten more sales down the road.
As far as I know Sol-Ark ships back returned inverters for free and Amazon pays shipping both ways without the customer being doubted.
no really robby, the solution here is really really simple.
customer buy an extra battery, as you should have read the freaking manual.

full stop

and to add , this also the reason sol-ark has a 300% upmark.
 

Koldsimer

Solar Addict
Joined
Dec 4, 2021
Messages
354
@houseofancients Signature tech should have noticed this very basic requirement and advised op of the requirements before suggesting something may be wrong with his battery and it should be sent back. Seems to me SS techs should shoulder some of the responsibility here.

For me, it comes down to making customers happy whenever possible and within reason. James, the owner of SS, just agreed that his tech team came up short here in their assessment of this situation. How SS doesn't recognize this and correct it by offering the guy a full refund is beyond me.

As everyone knows, SS is growing quickly and that causes certain growing pains. They really need to get a handle on customer service and have more stories like this end up with happy customers. The cost to do this would be a drop in the bucket all things considered.

The alternative is the potential for this thread to get 25k views with 1000+ responses. Is that worth keeping this guys money?
 

Browse

Solar Enthusiast
Joined
Mar 9, 2022
Messages
64
The customer learned a costly lesson. Unfortunately, we have all made these types of mistakes and it sucks to experience it and lose money which is already depreciating every day.

I don't believe Signature Solar is at fault here, other than their tech team missing the inverter specs. That took me all of 5 minutes to look up, but it is not their responsibility to investigate, re-spec and troubleshoot every DIYers setup. If the customer was advised to purchase a second battery, at least he would have had a choice in the decision to avert a possible restocking fee and return shipping expenses. Shipping costs for heavy items like this are pretty high right now. This isn't like returning a widget on Amazon.

Having a second battery, though expensive, has many advantages. That would have been the route I would have taken.
 

SparkyJJO

I have that name for a reason.
Joined
Jan 31, 2022
Messages
294
Location
Ohio
There's a reason why I wanted a LF inverter. Frickin HF dong some bonkers high current draw for starting a vacuum motor...

What is it with vacuums anyway? Every time we turn ours on, regardless of where in the house, the lights flicker for a moment. Must have some stupid high inrush on those things. And that is on grid power.
 

tomy2

escape artist
Joined
Mar 12, 2022
Messages
91
Location
paso robles ca.
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.
True that! I run five window Air conditioners in the rooms where people spend most their time and it still cheaper than my 4ton central Air. And you can run them off a smaller solar system.
 

RichardfromEG4

The "Do-What's-Needed" Solar Guy
Joined
Dec 23, 2021
Messages
847
Location
Sulphur Springs, TX
While I do believe the OP had less battery power than would be ideal I also think the EG4 has some issues with tripping to easily when loaded down. This is certainly not the first post where a user has had overload issue and yet another battery pack worked perfectly. I also remember a thread where a few guys just changed out the BMS in the EG4 to a different brand and the problem was solved.

What would be nice is to hear of a warranty issues being solved by Signature Solar that did not involve pages of Drama and an unhappy customer. Personally I think this whole "It works for us so your out of luck" warranty policy absolutely sucks. Maybe I missed the post where someone sent back something to SS and they actually said it did not work and just refunded them or replaced the item.
I'm at the Signature Solar office today for a few reasons, and just looked at their ticket status and back room. We have hundreds of tickets and items (for a number of reasons) where a customer received a full refund including shipping. I have personally dealt with tons of tickets where that's what we did for one reason or another. In fact, there are lots of times where a customer likely damaged the product, but they don't have a way to prove it so they still replace the unit. In this case we have a battery where they tried to troubleshoot this remotely, and even stated that they had a strong suspicion that it was something about the vacuum causing the issue. We have a tablesaw, huge shop vac, and tons of other equipment for testing that it just wouldn't make sense that the vacuum has a larger inrush current. We are talking about a little dirt devil vacuum - meanwhile the customer states the batteries are operating flawlessly otherwise with large loads, and devices we have to assume has a larger inrush current. The testing shows the battery operating to specs - the continuous amps held for an extended time period, and every over current fault met or exceeded the amperage listed for the timeframe listed per the manual.
Personally I think this whole "It works for us so your out of luck" warranty policy absolutely sucks.
This isn't specifically the policy. But during troubleshooting we tried to have the customer test the battery and it passed all our tests - we even suggested that it was likely something about the vacuum specifically that is causing the issues, and that we believed the battery was performing to specs. When going through the RMA, we clearly outline the outcomes: it's faulty and replaced or repaired at no cost (including shipping), or it's not faulty and performs to specs, and will either be sent back at cost for shipping or refunded less shipping incurred and a possible restocking fee. It is the choice of the customer which option they would like to select.
understanding and being okay with the consequences
This 100%. Signature Solar has a design team that will put together a system - in those circumstances, if an issue like this happens it's another story. They take responsibility 100% for overlooking something like requirements for an inverter etc. You can't have it both ways where you are paying DIY pricing and putting your own system together, then getting upset at a distributor when the system you designed doesn't work because the specs are incorrect.
before suggesting something may be wrong with his battery
Signature Solar didn't suggest something was wrong with his battery. They stated that there was something tripping the short circuit protection (exceeding 250a), that they believed it was the vacuum, and tried to have the customer test another vacuum. The customer said he didn't want to get another vacuum to test with, and the customer replied that he knew it wasn't the vacuum 100% and that he wanted to know the next steps in replacing the battery. It was at this time we sent him the RMA form (which outlines the outcomes for the customer depending on whether an issue was found or if it performed to specs), and he decided to continue with that process.
their responsibility to investigate, re-spec and troubleshoot every DIYers setup
100% this. We do everything we can to help people make decisions. Signature Solar sells all the equipment you need to set up a solar system, and has a design team dedicated to helping with this. As soon as someone opts to DIY and put their own system together, they are also accepting the responsibility to ensure it is compatible and within specs for operations.
agreed that his tech team came up short here in their assessment of this situation
He agreed that if the tech team did the research the customer should have done and found this information for him, that the disappointment could have been avoided. He didn't state that the tech team came up short, and regardless, they advised the customer that they believed the battery was operating to spec and that there was something tripping the short circuit protection (likely the vacuum somehow plus the inverter), but it is the customers decision on how to proceed.

In the time that I have been dealing with Signature Solar, I've never seen a company so engaged on public forums nor willing to go so far out of it's way to help customers at every stage of the process. Help designing a system, selling products without constantly upselling where it's not required, assisting with freight issues and claims , technical support, a very generous RMA process that for most is painless, and more. No matter what they do, they can't make everyone happy. There is always room for improvement but I really think we've done a great job and Signature Solar's customer service far exceeds what you will experience with nearly any other company.
 
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