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Schneider xw pro 6848 not powering up with eg4 lithium battery

Well, yes you should be able to do that. But the loads have to be turned on at some time. Just the inverter turning on and driving its 60Hz transformer for the first cycles can present a surge to the DC input some times.

I think you said that the inverter did not turn on long enough for the SCP to show anything. It needs to start up enough to do that at least. I can't remember if the SCP comes alive before the inverter's AC output ?
That's correct. When i start with the fla's the scp comes right on, fans spin and a second or two later the ac loads in the house have power. There's definitely a delay. I assume it's sensing for qualified power? When trying to start with the eg4's it just pulses and clicks. I let it go like this for about 3 or 4 seconds until it stopped, and the batteries alarm light turned on.
I would most likely try to understand why the system with the eg4 batteries are not working right.. You are going to need a battery.

What Schneider means by needing battery is that it is powered by the battery side of the inverter and not by the same grid input used for charging.

Most charge controllers work the same way... They are usually powered by the battery side and not the PV side.
Gotcha, thanks.
 
I have tried to power up with just one eg4 with no success. I did not cut all ac loads, but the only real startup surge is the fridge. Also when i fire up the system with the fla's the inverter hums, fans spin and it takes a couple seconds for house ac loads to get power, so i'm pretty sure that's not what's messing with the eg4's.

So, you haven't tried it with 2 or more eg4's ?? I would try two in parallel.


At this point, I'll be receiving the insight home tool to update my firmware next monday. Im going to try that and see what happens. Hope fully signature solar will have some new information.

I know its not exactly apples to apples, but my dads system has the same exact inverter/cc combo with discover lithium batteries and i had zero issues commissioning his system- been running perfectly for 8 months now. I know the discover batteries communicate directly with the inverter but it still seems they would go through the same start up inrush of current. He is running a much newer firmware version.

What is the amp-hour difference between your 3g4 and your dad's batteries ? Was your dad's also 48V ?
 
So, you haven't tried it with 2 or more eg4's ?? I would try two in parallel.
I first tried with all four paralleled, then one on its own, then another on its own. Same results every time.
What is the amp-hour difference between your 3g4 and your dad's batteries ? Was your dad's also 48V ?
Yeah, he has the exact same setup inverter and cc combo albeit with a newer firmware version. Hes running two of the 48v discover in parallel for 260ah with zero issues since day one. The eg4's are 100ah each and ive got 4.
 
Yeah, he has the exact same setup inverter and cc combo albeit with a newer firmware version. He’s running two of the 48v discover in parallel for 260ah with zero issues since day one.


I know it doesn’t help you but I’ve been running my CSW 4048 with one 48V EG4 with zero issues since day one well over a year ago.

Hope the firmware update gets it all going and you have a Happy New Year!
 
Have you tried lead-acid parallel with lithium?
Or, power up with lead-acid, parallel with lithium, disconnect lead-acid.

But make sure the lithium (and fuse) works. Try powering some load with it. e.g. four automotive light head or tail light bulbs.
 
I'd call the manufacturer myself. It shouldn't do that.

You have another 48V battery you can try ? Sorry, I didn't re-read your OP

Or a power supply ?
 
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Have you tried lead-acid parallel with lithium?
Or, power up with lead-acid, parallel with lithium, disconnect lead-acid.

But make sure the lithium (and fuse) works. Try powering some load with it. e.g. four automotive light head or tail light bulbs.
It has been suggested but i have not tried it. I can see how it should work, and it likely will work but it's not a long term permanent solution obviously. Not gonna keep 1000lbs of batteries under my house just so i can use them to help jump start my inverter for the lithiums every time i do a system shutdown/startup.

I'm gonna see if i can rig up a 48 volt load like you suggested and see what happens with the battery when i just try to power a simple 48v load.
 
I would definitely say it's the battery or the BMS. No question in my mind after reading all this.

I do not believe the XW firmware has anything to do with it.

As I re-read your post (#41), the "pulses and clicks" is the XW trying to start on reduced voltage. This is exactly what my SW does when I push the resistor button for too long. (and this is why I have questioned the resistor before throwing the breaker method for the SW start up. The clicking and pulsing does not seem healthy). But as soon as I throw the breaker with LFP connected, inverter powers up like normal.

As you've noted, the input voltage is so low the XW & SCP cannot even register a low input voltage error because it can't even start up enough.

Have you tried taking a voltage reading with a DVM of the battery once the pulsing and clicking starts. It would not take but just a sec and then you can turn it back off. I think I would do this for reference. Then you can confirm to yourself and Sig Solar that the batteries or bms are not providing enough voltage to the XW .

It just seems it's a bms or bad cell that sags under any load. But odd it would b all 4.

I think I'd be on the phone with Sig today asking for a prepaid RMA and shipping label.
 
I question the use of a pre charge resistor and button for the start up of the SW and XW. The pulsing and clicking do not seem healthy. I do not know...
1. If it should not be done with these Schneider inverters, or
2. That I have a resistor that's wrong sized, or
3. That I am holding the resistor button too long (I stopped holding it longer than just a second so the pulsing and clicking doesn't start)

But what you describe is exactly what I see using a precharge resistor too long.
 
I would definitely say it's the battery or the BMS. No question in my mind after reading all this.

I do not believe the XW firmware has anything to do with it.

Agree 100%.
As I re-read your post (#41), the "pulses and clicks" is the XW trying to start on reduced voltage. This is exactly what my SW does when I push the resistor button for too long. (and this is why I have questioned the resistor before throwing the breaker method for the SW start up. The clicking and pulsing does not seem healthy). But as soon as I throw the breaker with LFP connected, inverter powers up like normal.

Exactly why i'm getting w48 warning, low voltage. I've read your entire thread regarding the pre-charge resistor (excellent), just not sure if that would really help my situation at all. I understand the theory but i still think the battery cutting current prematurely is the primary fault that i would like to address first.
As you've noted, the input voltage is so low the XW & SCP cannot even register a low input voltage error because it can't even start up enough.

Have you tried taking a voltage reading with a DVM of the battery once the pulsing and clicking starts. It would not take but just a sec and then you can turn it back off. I think I would do this for reference. Then you can confirm to yourself and Sig Solar that the batteries or bms are not providing enough voltage to the XW

I've just got a cheap 20$ multi meter. Please don't ban me!
.

It just seems it's a bms or bad cell that sags under any load. But odd it would b all 4.

I think I'd be on the phone with Sig today asking for a prepaid RMA and shipping label.
Gotta be a bms setting issue. Hopefully signature will reach out to me today with an answer.

Thanks
 
I really want to thank everyone for their input. It takes time to explain these things and I appreciate everyones patience and input. It's really helping me learn and understand my system better even if i cant get these batteries to work!
 
Any digital volt meter will work as long as long as it reads dc volts.

And I'm not suggesting you try a resistor, just noting that's what happens when a resistor is limiting voltage.
 
Do your rack batteries have Bluetooth or some form of communication to monitor each cell and to program bms settings?

That would be nice.

But with a monitoring app you could see 1) if a single cell is sagging or 2) if the BMS is turning off discharge due to low voltage.
 
On Tuesday, with Signature Techs on the phone, i got into the bms and took these screenshots to send to them. The history file shows no malfunction or even activity. This was after several attempts to power up the inverter.
 

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It has been suggested but i have not tried it. I can see how it should work, and it likely will work but it's not a long term permanent solution obviously. Not gonna keep 1000lbs of batteries under my house just so i can use them to help jump start my inverter for the lithiums every time i do a system shutdown/startup.

Not as a permanent solution, but as a test to see if lithium can supply the inverter, even though they have trouble precharging it.

If the inverter could have its capacitors precharged and sit there not drawing any power beyond a few watts for its microprocessor, or even if it started up and drew idle current of 25 or 50 watts generating A/C but loads were disconnected, should be possible to precharge through a resistor, then close switch.

50V 50W is about 1A.
1A through a 1 ohms resistor is 1W steady-state.
50V / 1 ohms is 50A
50V x 50A = 2500W (pulse during precharge)

Some resistors would pop with such a surge, while others could take it. Look for "pulse rated".
A suitable resistor could precharge and power up the inverter so long as loads disconnected, allowing you unlimited time to close switch.

Lead-acid alternative, four small 12V gel-cells might be 50 lbs or less. Series for precharge, rewired in parallel they could serve as a jumpstarter.

Another precharge test: Just use the lithium batteries, but higher resistance wire. Did you make it nice and short? Try a long pair of jumper cables. That could carry full current for a limited time. Jumper cables across switch/breaker, then close switch.

For higher resistance but limited current handling, a 250' roll of 12 awg Romex. Connect white and black together at far end. Use briefly to precharge.

I'm gonna see if i can rig up a 48 volt load like you suggested and see what happens with the battery when i just try to power a simple 48v load.

Yes, this should show if BMS or fuse is dead.
 
There is just so much of this that i am not comfortable doing on my own. I can't risk ruining my inverter- can't afford a replacement or even service at this point- just spent all my money on these eg4's hoping the investment would serve us long into the future.

Still no word from Signature. Not surprised with the holiday i guess.

Gonna speak with a schneider tech today about keeping the inverter powered with the cc's while performing battery swap. Hopefully they will give the ok but not likely imo.

If I can get ahold of someone at Signature i'm going to see if they are ok with me hooking up the eg4's and jumping my fla's over to the bus bar to try and power up that way.
 
Most charge controllers work the same way... They are usually powered by the battery side and not the PV side.

boB
So wouldn't my midnite classics just turn themselves off when i disconnect battery at dc breaker? I have always thought they would stay on due to pv power but have never tried as i have always turned them off first and on last when stopping/starting system.
 
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