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SS EG4 12V 400AH - Disappointing BMS

Just came across this now as I had my first issue with my 48V EG4-LifePower4 I purchased a couple months ago. I'm using it to backup circuits in the house (few lights, home office outlets and the well pump as to not pull out the generator for water for short duration outages). We had a power outage yesterday and the inverter (Sungold Power 48V 6000W) didn't switch over as expected. I've tested before by switching off the AC supply into the inverter to simulate a power disruption and it's always been fine but never had the well pump on (or come on) during those tests or some other heavy loads active. Battery was flashing red "alarm".

The well pump (3/4hp ~900W when running) was on at the time as I was watering the garden and from reading everything in here, it wasn't the inrush current as it was running, rather the huge demand when the inverter switched off AC to battery. I don't know 100% but there was maybe 1500W max on at the time on those circuits with the pump on. Now I'm thinking if I have more than a 1000W and the power fails and the inverter kicks over, it's just going to die so the whole UPS "backup" seems pretty useless at this point.

I have the BMS monitoring tool hooked up but can't get to the historical tab due to the "password" but suspect it will just convey it was "short circuit" protection or whatever. Looks like I may have to go the Overkill BMS route and tell everyone in our local Solar group to steer clear of these batteries or at least the model I got.
 
Same issue here going back many months. Fault mode with only 13 amps inrush.I purchased 2 of SS 24 volt battery packs put on a overkill Bms hooked it up to my system and all is well. Live and learn I say. I can't say they didn't try to help, but a good try that doesn't fix a problem is worthless.
 
Same issue here going back many months. Fault mode with only 13 amps inrush.I purchased 2 of SS 24 volt battery packs put on a overkill Bms hooked it up to my system and all is well. Live and learn I say. I can't say they didn't try to help, but a good try that doesn't fix a problem is worthless.
I thought got this sorted with new batches and revision to the bms
 
Just came across this now as I had my first issue with my 48V EG4-LifePower4 I purchased a couple months ago. I'm using it to backup circuits in the house (few lights, home office outlets and the well pump as to not pull out the generator for water for short duration outages). We had a power outage yesterday and the inverter (Sungold Power 48V 6000W) didn't switch over as expected. I've tested before by switching off the AC supply into the inverter to simulate a power disruption and it's always been fine but never had the well pump on (or come on) during those tests or some other heavy loads active. Battery was flashing red "alarm".

The well pump (3/4hp ~900W when running) was on at the time as I was watering the garden and from reading everything in here, it wasn't the inrush current as it was running, rather the huge demand when the inverter switched off AC to battery. I don't know 100% but there was maybe 1500W max on at the time on those circuits with the pump on. Now I'm thinking if I have more than a 1000W and the power fails and the inverter kicks over, it's just going to die so the whole UPS "backup" seems pretty useless at this point.

I have the BMS monitoring tool hooked up but can't get to the historical tab due to the "password" but suspect it will just convey it was "short circuit" protection or whatever. Looks like I may have to go the Overkill BMS route and tell everyone in our local Solar group to steer clear of these batteries or at least the model I got.
Some say JK is better .
After installing a number of Overkill bms.
I had one fried after attepmting to set my cell cell parameters .
I have found bluetooth on Overkill bms on android app.tends to be sluggish and sometimes unresponsive.

So i will be trying the jk bms wit active balancer.
 
Hey all just reading this after having similar issues.

SS has given me different answers on this but I really just need to know if I need to ditch my 2000W inverter and get a smaller one I want to run one of these 12V400ah batteries in my van. It seems really poor to have all that power and not be able to run a 2000W inverter.

My Experience:
All wired up and when I turn on the inverter it faults the Battery (Lifepower4 5.12kw) +(2000WRenogyPS) and then alarms the inverter. Did it pull some crazy amount of current to fault the battery? I think so, with the BMS seeming to have a limit of 200 or 250 or 100 amps depending on the SS document of the moment. But I have a 250amp terminal fuse coming off my pos terminal. And it did not blow. So? Not the crazy current? Maybe less than 250amps, if my fuse is not crap.

And of course if I turn off the inverter and reset the battery the inverter runs fine half the time and I can power all kinds of stuff with no issue. BMS program shows the battery at 100% SOH so must not be an issue. But I don't want to hurt the battery and the SS agents have told me that pulling "40% of the power of the bettery is not recommended." I have the stupid thing so I can pull power from it :D!!!

So 2000W (4000W surge) pulls 4000/5120 W so 78% of the battery for a moment on startup. And if I use all 2000W on the blender and heat gun and whatever else I would pull 2000/5120 W so 39%. So I can come in under the "recommended draw" with a 2000W inverter but my battery alarms out everytime because of the initial surge. I'm new to this whole world but it seems like a huge waste to not be able to use the power of this battery. OP makes a great point about the hose situation.

Can I override the BMS from being concerened about the (less than 250amps) for that surge moment?
Can I get and inverter that won't surge it too hard (1000W)?


In all of this the inverter has run after I reset it past it's initial qualms for days now, with no issue. And basically SS told me I should just buy another battery. Wahoo!

Was there ever any solution here besides ripping the BMS?
Seems there is an inrush current glitch?

@RichardfromEG4
 
Hey all just reading this after having similar issues.

SS has given me different answers on this but I really just need to know if I need to ditch my 2000W inverter and get a smaller one I want to run one of these 12V400ah batteries in my van. It seems really poor to have all that power and not be able to run a 2000W inverter.

My Experience:
All wired up and when I turn on the inverter it faults the Battery (Lifepower4 5.12kw) +(2000WRenogyPS) and then alarms the inverter. Did it pull some crazy amount of current to fault the battery? I think so, with the BMS seeming to have a limit of 200 or 250 or 100 amps depending on the SS document of the moment. But I have a 250amp terminal fuse coming off my pos terminal. And it did not blow. So? Not the crazy current? Maybe less than 250amps, if my fuse is not crap.

And of course if I turn off the inverter and reset the battery the inverter runs fine half the time and I can power all kinds of stuff with no issue. BMS program shows the battery at 100% SOH so must not be an issue. But I don't want to hurt the battery and the SS agents have told me that pulling "40% of the power of the bettery is not recommended." I have the stupid thing so I can pull power from it :D!!!

So 2000W (4000W surge) pulls 4000/5120 W so 78% of the battery for a moment on startup. And if I use all 2000W on the blender and heat gun and whatever else I would pull 2000/5120 W so 39%. So I can come in under the "recommended draw" with a 2000W inverter but my battery alarms out everytime because of the initial surge. I'm new to this whole world but it seems like a huge waste to not be able to use the power of this battery. OP makes a great point about the hose situation.

Can I override the BMS from being concerened about the (less than 250amps) for that surge moment?
Can I get and inverter that won't surge it too hard (1000W)?


In all of this the inverter has run after I reset it past it's initial qualms for days now, with no issue. And basically SS told me I should just buy another battery. Wahoo!

Was there ever any solution here besides ripping the BMS?
Seems there is an inrush current glitch?

@RichardfromEG4
did you use the correct startup procedure ?
 
Was there ever any solution here besides ripping the BMS?
Seems there is an inrush current glitch?

@RichardfromEG4

Not that I ever found.

The BMS software is shit and unprogrammable

I think at this point, enough dang people have had the same issue with inrush and such, it’s on SS or EG4 to admit this issue and step up and fix it for real with a different BMS and software package
 
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did you use the correct startup procedure ?
Never heard of it, i did find a video online about it that was posted this week. The “procedure” is to hook up the inverter and then turn the battery on and then turn the inverter on? I mean I cannot imagine another order ? so I believe i followed that procedure. Unless there is something I don’t know about? Please elaborate if so.
 
Never heard of it, i did find a video online about it that was posted this week. The “procedure” is to hook up the inverter and then turn the battery on and then turn the inverter on? I mean I cannot imagine another order ? so I believe i followed that procedure. Unless there is something I don’t know about? Please elaborate if so.
this makes sure the precharge procedure of the bms has passed by and the inverter doesnt pull a huge in rush upon start
 
this makes sure the precharge procedure of the bms has passed by and the inverter doesnt pull a huge in rush upon start
I can appreciate this. I would like to follow the correct procedure and avoid the fault on the battery but cannot find anything in the manual about this process.


I found this video from Rich abouut the pre charging. But again, I got nothing from the video as I do have the inverter connected to the battery before startup. Even if the battery has been on, connected to the inverter for hours, runnung all kinds of 12V loads, if I start the Inverter it all alarms out. Is it possible the inverter should be "on" when I start the battery up. Because I don't think that it right. Appreciate any guidance.

 
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It’s the BMS that has an issue.
I can start my 1000W Inverter with a 12v 9Ah UPS battery with no problem.
There are just way to many of these stories on the forum for it to be a coincidence. The fix always seems to be shipping it back and get an LL model or changing the bms.
 
A bit weird maybe. But if I just flip "on" the inverter via the remote switch and then turn on the battery everything runs fine. No alarms or issues, works fine. Is that all I had to do to pre charge the resistors then. wow. Seems counter intuitive to me but if it runs it runs. Perhaps that was it. Wiring if curious.


Seems that could have been it but SS staff had no clue how to do this pre charge resistor bizz. Told me I should "get a new another battery". Leaves me feeling odd about future purchases.


EXACT SET UP EDITS: 250amp fuse on battery. And inverter cables on inverter, not 2 awg. Sorry if that is confusing.
Blank diagram.png
 
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A bit weird maybe. But if I just flip "on" the inverter via the remote switch and then turn on the battery everything runs fine. No alarms or issues, works fine. Is that all I had to do to pre charge the resistors then. wow. Seems counter intuitive to me but if it runs it runs. Perhaps that was it. Wiring if curious. 250amp fuse off the battery is the edit on this.


Seems that could have been it but SS staff had no clue how to do this pre charge resistor bizz. Told me I should "get a new another battery". Leaves me feeling odd about future purchases.

View attachment 100314
this is stipulated in the startup procedure as shown by ss
 
this is stipulated in the startup procedure as shown by ss
If we are going off of that video I would disagree. He turns "on" the inverter after turning "on" the battery. I am turning "on" the inverter before turning "on" the battery. Is there another procedure somewhere that I am unaware of. Not mentioned in manual. It even says that you should do the opposite in the manual.

1656345164834.png
 
?This is all very interesting as I have been considering 12V Server rack batteries. I’ve been trying to determine if they would be suitable for van/RV life if I put them on a good cushion but seeing these problems on this thread makes me much less interested in them. Oh snap.
 
A bit weird maybe. But if I just flip "on" the inverter via the remote switch and then turn on the battery everything runs fine. No alarms or issues, works fine. Is that all I had to do to pre charge the resistors then. wow. Seems counter intuitive to me but if it runs it runs. Perhaps that was it. Wiring if curious. 250amp fuse off the battery is the edit on this.


Seems that could have been it but SS staff had no clue how to do this pre charge resistor bizz. Told me I should "get a new another battery". Leaves me feeling odd about future purchases.

View attachment 100314
Pure copper 2 awg wire with 105C insulation can be fused no higher than 200 amps.
Pure copper 2/0 awg wire with 105C insulation can be fused no higher than 300 amps.
As it stands your wires are protecting the fuses and not the other way around.
 
Pure copper 2 awg wire with 105C insulation can be fused no higher than 200 amps.
Pure copper 2/0 awg wire with 105C insulation can be fused no higher than 300 amps.
As it stands your wires are protecting the fuses and not the other way around.
Hey I think I know what you are talking about but this diagram is not exactly as it is hooked up, I just didn't want to pay for the subscription to edit it. My battery cables are 2/0 and fused at 250 amps not 400amps (Because of the discharge limit on the BMS). And I ended up using the inverter cables that it came with (look like 2x 4awg maybe) and that is actually fused at 250 as well. Both terminal fuses.
 
Hey I think I know what you are talking about but this diagram is not exactly as it is hooked up, I just didn't want to pay for the subscription to edit it. My battery cables are 2/0 and fused at 250 amps not 400amps (Because of the discharge limit on the BMS). And I ended up using the inverter cables that it came with (look like 2x 4awg maybe) and that is actually fused at 250 as well. Both terminal fuses.
The cables that come with inverters usually should be thrown out with the packing peanuts.
 
The cables that come with inverters usually should be thrown out with the packing peanuts.
They don't seem to be of the highest quality, I would consider swapping them eventually. But otherwise I addressed your concerns yea?
 
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