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Schneider xw pro 6848 not powering up with eg4 lithium battery

I should be able to provide more info soon, my batteries are on the way "I think", at least I got emailed a tracking number, but I can't tell where they are with it.

The packs DO have pre-charge resisters and external ones should NOT be needed. HOWEVER, none of us seem to know how the pre-charge function initiates and works in these batteries and it's not documented in the manual. WE need to know that!

My best guess with the info I've read on here is the Schneider inverters have trouble starting with them, because they power up when power is applied to the DC Input "they don't have an on/off switch". It seems that the batteries are still in pre-charge mode with their built in resister during this boot up process and the Schneider pulls too much during initialization thru the pre-charge resistor. The voltage drops and the inverter doesn't start.

I have duplicated this on my lead acid batteries using a pre-charge resister "lightbulb" with my XW Pro.
 
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Mr-Sandman said:
My best guess with the info I've read on here is the Schneider inverters have trouble starting with them, because they power up when power is applied to the DC Input "they don't have an on/off switch". It seems that the batteries are still in pre-charge mode with their built in resister during this boot up process and the Schneider pulls too much during initialization thru the pre-charge resistor. The voltage drops and the inverter doesn't start.
Click to expand...

Seems likely. Precharge and application of load have to be designed to work together.
Battery manufacturer probably designed and tested it with some inverter that had a delay before trying to make AC.

With no AC load applied, inverter might consume 25W or so, 0.5A at 50V. Precharge resistor of low enough value could supply that with < 5% voltage drop, but still limit short-circuit current (into discharged capacitors) to less than 200A. 5 ohms max, 0.25 ohm min.

If heavier AC loads are applied before completing precharge and closing switch (FETs), voltage collapses. Resistor will overheat. Having a suitable resistor value and disconnecting AC load would be an improvement, but you're apparently working with a precharge resistor built into the battery.

My idea of coil of Romex for precharge resistor won't help if BMS has higher value resistor and inverter turns on too soon.
Power up with lead-acid, then parallel with lithium, then lithium only should work.
Another idea: Have BMS precharge a large (e.g. Super) capacitor bank. Then connect inverter (ideally first precharged through my Romex "resistor", then close heavy switch.)
 
The Schneider inverters start in standby mode or at least mine always has "maybe because I put it in standby before pulling DC power". However during the startup there appears to be several test ran "clicking and fans ramping up, etc". I think there's some notable current draw during startup, even without AC load present in these, beyond just charging the capacitors.

I hate to keep posting guesses, but I think your right, it's going to take an external 48v power source great enough to start the Schneider Inverters, IF it is indeed the pre-charge in the batteries causing this and it's not adjustable.
 
Quattrohead said:
This link tells us what we need to know about the general idea - http://liionbms.com/php/precharge.php
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This supports what I posted earlier in post #119: The pre-charge circuit doesn't just happen when you connect a big load to it. The mechanism is controlled - probably - by the BMS. So you need to initiate the circuit from the battery. Not sure I'm getting that message through though.
 
@Signature Solar
@SignatureSolarUS
@signaturesolarrichard

Signature Solar guys, we would like to know EXACTLY how the EG4 Lifepower4 battery Pre-Charge circuit works in your batteries. What initializes it? How long does it Pre-Charge? Based on timer or current? It's not in the manual, so can you provide us with details on this feature?

If you care to read the 7 pages of troubleshooting in this thread, there appears to be an issue with your EG4 batteries starting Schneider Inverters. I think it's related to how the Schneider inverters power up as soon as DC power is supplied and the EG4 batteries in pre-charge during this startup causes voltage to drop to low.
 
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Horsefly said:
This supports what I posted earlier in post #119: The pre-charge circuit doesn't just happen when you connect a big load to it. The mechanism is controlled - probably - by the BMS. So you need to initiate the circuit from the battery. Not sure I'm getting that message through though.
Click to expand...
I'm getting it. Big sparks don't frighten me, I have worked on 480V 3 phase systems with highly conductive liquids around.....that is bad sh!t.
Most people not in the know think a spark is a short circuit and poo !!!!!
 
Mr-Sandman said:
@Signature Solar
@SignatureSolarUS
@signaturesolarrichard

Signature Solar guys, we would like to know EXACTLY how the EG4 Lifepower4 battery Pre-Charge circuit works in your batteries. What initializes it? How long does it Pre-Charge? Based on timer or current? It's not in the manual, so can you provide us with details on this feature?

If you care to read the 7 pages of troubleshooting in this thread, there appears to be an issue with your EG4 batteries starting Schneider Inverters. I think it's related to how the Schneider inverters power up as soon as DC power is supplied and the EG4 batteries in pre-charge during this startup causes voltage to drop to low.
Click to expand...
Signature Solars last email to me was two days ago and they were asking if I had tried the pre-charging with a resistor. Of course, that's not including their genius advice in this forum in a separate thread regarding their chargers of "maybe i should just try the batteries and let them know how they work"

Left hand, meet right hand.

They have been tagged way back in this thread and didn't bother to respond or offer anything so I doubt we will get any help from them.

I'm afraid it's up to us to figure out the eg4 Schneider compatibility issue.

Thanks again for everyones help

Like I have said several times, they are nice people with a good cause but i can't believe how little help they have been. Guess they are too busy selling batteries. Beyond dissapointed.



And my batteries still don't work with my Schneider 6848.
 
This is not a good sign for a company that markets themselves to the DIY community. I hope they redeem themselves soon and help with this issue with their EG4 batteries.
 
Horsefly said:
Like I said yesterday (or was it day before yesterday?), but I'm not sure it got traction: @RCinFLA made a good point early on in this thread. If a battery has a pre-charge resistor, something needs to route the power through the pre-charge resistor before the regular power directly from the battery to the load. Just connecting it to the load (the inverter in this case) doesn't do it. How would the battery know to switch to the pre-charge.

Rather, it seems like the pre-charge must be enabled from the battery itself. That is, the BMS would have to route power through the pre-charge before attempting to connect directly to the load.

Have you tried to have the battery turned off, turn on the main breaker between the inverter and the battery, and THEN turn on the battery? Maybe that forces the connection through the pre-charge before connecting the battery directly to the inverter.
Click to expand...

I have tried this exact method. Schneider released an addendum that was a guide for commissioning with different lithium batteries. Eg4 was not listed btw. One thing i noticed is that for many batteries their instructions are exactly what you recommend. Close dc breaker then power up batteries. I tried that with one battery, two in parallel with communication, two without communication, all four in parallel with/without communication.... same result every time
 
SignatureSolarRay said:
So to be clear:
4x 48v LIFEPOWER4 packs are being powered on, then the DC breaker for the Schneider 6848 is being engaged after the 4 packs have powered on?
Click to expand...
He just addressed that he has tried it in the other order, i.e. close the main breaker between the batteries and the inverter, then power up a battery. No go. He posted this two messages before yours:
Koldsimer said:
I have tried this exact method. Schneider released an addendum that was a guide for commissioning with different lithium batteries. Eg4 was not listed btw. One thing i noticed is that for many batteries their instructions are exactly what you recommend. Close dc breaker then power up batteries. I tried that with one battery, two in parallel with communication, two without communication, all four in parallel with/without communication.... same result every time
Click to expand...
 
Mr-Sandman said:
@Signature Solar
@SignatureSolarUS
@signaturesolarrichard

Signature Solar guys, we would like to know EXACTLY how the EG4 Lifepower4 battery Pre-Charge circuit works in your batteries. What initializes it? How long does it Pre-Charge? Based on timer or current? It's not in the manual, so can you provide us with details on this feature?

If you care to read the 7 pages of troubleshooting in this thread, there appears to be an issue with your EG4 batteries starting Schneider Inverters. I think it's related to how the Schneider inverters power up as soon as DC power is supplied and the EG4 batteries in pre-charge during this startup causes voltage to drop to low.
Click to expand...
I'll do some research for you. Thanks for the tag!
 
Mr-Sandman said:
@Signature Solar
@SignatureSolarUS
@signaturesolarrichard

Signature Solar guys, we would like to know EXACTLY how the EG4 Lifepower4 battery Pre-Charge circuit works in your batteries. What initializes it? How long does it Pre-Charge? Based on timer or current? It's not in the manual, so can you provide us with details on this feature?

If you care to read the 7 pages of troubleshooting in this thread, there appears to be an issue with your EG4 batteries starting Schneider Inverters. I think it's related to how the Schneider inverters power up as soon as DC power is supplied and the EG4 batteries in pre-charge during this startup causes voltage to drop to low.
Click to expand...
Here's some info I've found out from our engineering team. I'll get more details once we review the schematics:
How it works - It briefly allows a short between the output of the battery the prevent the full electrical charge from entering the battery. This short is in PARALLEL with the additional electricity that is used to precharge the resistor. It is TIME BASED (I am looking to find an exact number on how long this is, but at this time I don't have that information. We believe it is nearly instantaneous from connection to turning off the resistor.) I'll see if I can find more info or documentation and will provide info as I come by it. Thanks!
 
signaturesolarrichard said:
Here's some info I've found out from our engineering team. I'll get more details once we review the schematics:
How it works - It briefly allows a short between the output of the battery the prevent the full electrical charge from entering the battery. This short is in PARALLEL with the additional electricity that is used to precharge the resistor. It is TIME BASED (I am looking to find an exact number on how long this is, but at this time I don't have that information. We believe it is nearly instantaneous from connection to turning off the resistor.) I'll see if I can find more info or documentation and will provide info as I come by it. Thanks!
Click to expand...
If it's time based, they @Koldsimer , maybe you are not leaving the battery connected to the XW (when the XW is in pulse and blink mode). That is not long enough for the battery to switch from resistor to full battery.

My only problem with this is, I do not know if this is good for the XW to pulse and blink with supper low voltage. Its like it gets stuck in a "cant start" mode. It does not seem like this would be good for the electronics in side.
 
MrM1 said:
If it's time based, they @Koldsimer , maybe you are not leaving the battery connected to the XW (when the XW is in pulse and blink mode). That is not long enough for the battery to switch from resistor to full battery.

My only problem with this is, I do not know if this is good for the XW to pulse and blink with supper low voltage. Its like it gets stuck in a "cant start" mode. It does not seem like this would be good for the electronics in side.
Click to expand...
Yes, I'm not sure of the best solution if this is the case or something similar.
 
I'd say it's for sure not good to have the low voltage cause the XW Pro to not finish initializing. I'm not sure if it can recover at that point without starting the power cycle over.

Another question for Signature Solar folks. Is the Pre-Charge parameters configurable at all in the BMS? Like disable/enable pre charge resistor or TIMER for how long Pre-charge is on before BMS connects?
 
I think it probably needs to just be turned off, or set to only come on for a few hundred milliseconds.

I know with my SW, it does the same thing if I hold the pre-charge resistor button too long. But even once it starts into the pulse and blink cant start mode, once I let go of the button, and the battery delivers full voltage, the SW starts no problem
 
Agreed, my XW PRO did this as well, when trying to pre charge it before I hooked it to the lead acid battery bank.
It seem the EG4 batteries must have a longish pre-charge timer causing the XW to fail during initialization.
 
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