SOLVED: EG4 Lifepower4 24v dead battery reading on Magnum 4k hybrid inverter.

Posted my solution in the original thread and updated the title.

McRod said:

Posted my solution in the original thread and updated the title.

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Kind of funny seeing those two little batteries doing something that the EG4 cannot do.
I think that this solution is going to be problematic for all the reasons you stated. I hope you can monitor the cells in those 12V packs because i think everything is going to be going all over the place.

robby said:

Kind of funny seeing those two little batteries doing something that the EG4 cannot do.
I think that this solution is going to be problematic for all the reasons you stated. I hope you can monitor the cells in those 12V packs because i think everything is going to be going all over the place.

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Yes, it will be a challenge to keep them equally charged. There are some additional tweeks that I can do to the wiring to help mitigate. Construct cables to equal lengths, wire directly to the bussbar, buy a Victron battery balancer... But..

I don't think I will keep the "little" Big Batteries attached as a permanent solution. Most likely, I will purchase a 3rd 200AH non-EG4 Lifepower server rack battery to couple with the system.

robby said:

Kind of funny seeing those two little batteries doing something that the EG4 cannot do.

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Considering that he refused to take a measurement of how badly his wiring was sharing current, and they were wired "the worst possible way" (to quote will prowse), it's not surprising that spreading load across more cells and wires got him through the issue, whether it was a momentary DC ripple voltage overload or he's simply current/amps overloading a BMS momentarily.

Watching people throw money around like that, while also refusing to understand what they're doing, is both amusing and disturbing... Yes, go buy another server rack battery without finding out whether just fixing your wiring would resolve it.

Lilikoi_Heavy_Industries said:

Considering that he refused to take a measurement of how badly his wiring was sharing current, and they were wired "the worst possible way" (to quote will prowse), it's not surprising that spreading load across more cells and wires got him through the issue, whether it was a momentary DC ripple voltage overload or he's simply current/amps overloading a BMS momentarily.

Watching people throw money around like that, while also refusing to understand what they're doing, is both amusing and disturbing... Yes, go buy another server rack battery without finding out whether just fixing your wiring would resolve it.

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Not everybody has a clamp on DC Amp meter and his wiring while not the best should start an inverter without an a problem. Why is it that those two tiny 12 Batteries can start it up alone and yet the two 24V EG4s cannot start it?

robby said:

Not everybody has a clamp on DC Amp meter

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My clamp meter was pretty cheap on amazon, and it works.

robby said:

and his wiring while not the best should start an inverter without an a problem.

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Insisting that it's someone else's problem while doing everything wrong is clownish behavior. *honk honk*

robby said:

Why is it that those two tiny 12 Batteries can start it up alone and yet the two 24V EG4s cannot start it?

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He didn't start it up alone, he added it as a third 24v battery, which does in fact reduce current load on the first battery BMS, even with the worst possible wiring pattern for current sharing.

12V lithium batteries need to be setup to be able to handle twice as much current to provide the same number of watts as a 24v battery, so there's a very good reason that two 12V batteries of this type would be expected to put more amps out than a 24V design. So it's actually using the capacity of two BMS units, not just one, to serve as this final/third 24V part of the battery.

Also, why wouldn't the two other batteries be able to start it on their own? They might have a different allowed surge on their BMS. Different products have different specs.

robby said:

Not everybody has a clamp on DC Amp meter and his wiring while not the best should start an inverter without an a problem. Why is it that those two tiny 12 Batteries can start it up alone and yet the two 24V EG4s cannot start it?

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The BMS's appear to be too finicky.
Although, mine is working fine. (Knock on wood)

timselectric said:

The BMS's appear to be too finicky.
Although, mine is working fine. (Knock on wood)

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"finicky" probably just means it cuts off faster when it hits the overcurrent condition, but sure.

I bought two battery packs just in case, but I found that a single pack is actually able to do everything for me.

Strange how they work better for people who design their systems for low current operations!

A properly designed system, takes into account. All of the individual parts limitations. Maybe the solution is to change the discharge ratings.

Lilikoi_Heavy_Industries said:

My clamp meter was pretty cheap on amazon, and it works.

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Yes if you have one but a lot of people don't have one as they did not think they would need it.

Lilikoi_Heavy_Industries said:

Insisting that it's someone else's problem while doing everything wrong is clownish behavior. *honk honk*

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There are a lot of people on this forum with the same problem. I think we average about 2-3 posts per week of EG4 not starting the Inverter or EG4 tripping.

Lilikoi_Heavy_Industries said:

He didn't start it up alone, he added it as a third 24v battery, which does in fact reduce current load on the first battery BMS, even with the worst possible wiring pattern for current sharing.

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My undersanding is that the Inverter worked just fine with that battery alone before he got the Eg4.

Lilikoi_Heavy_Industries said:

12V lithium batteries need to be setup to be able to handle twice as much current to provide the same number of watts as a 24v battery, so there's a very good reason that two 12V batteries of this type would be expected to put more amps out than a 24V design. So it's actually using the capacity of two BMS units, not just one, to serve as this final/third 24V part of the battery.

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Your making it sound like putting BMS systems in Series is a good thing?

Lilikoi_Heavy_Industries said:

Also, why wouldn't the two other batteries be able to start it on their own? They might have a different allowed surge on their BMS. Different products have different specs.

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Yes and the point is that the Spec for the EG4 when it comes to surge current seems to be very low.

timselectric said:

The BMS's appear to be too finicky.
Although, mine is working fine. (Knock on wood)

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Yep there is something up with it and they don't seem to know what it is or they are not telling.

robby said:

Yes if you have one but a lot of people don't have one as they did not think they would need it.

There are a lot of people on this forum with the same problem. I think we average about 2-3 posts per week of EG4 not starting the Inverter or EG4 tripping.

My undersanding is that the Inverter worked just fine with that battery alone before he got the Eg4.

Your making it sound like putting BMS systems in Series is a good thing?

Yes and the point is that the Spec for the EG4 when it comes to surge current seems to be very low.

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Robby, this guy just wants a place on the internet to argue. He is not worth the time to respond to.

If he had read post#1 he would see that I did, in fact, run the inverter using ONLY the two 12v batteries, which have way less capacity than the 2 EG4s. He is making false assumptions across the internet, like I am sitting here waiting for instructions on what to do. When in fact I have been all over this system, with a dvm in hand, performing diagnosis and analysis. I am not going to post three weeks of evaluation steps, what tools I use on evaluation, which includes concurrent problem diagnosis from others having the same issue to the 74th jackwagon that stumbles into the middle of the conversation.

Step 1. Read all the posts before you open your mouth or risk looking like a baffoon.
Posting a couple of videos which succinctly outlines the problem and a "work around" to hopefully help others. The real solution is required by EG4 and Signature solar on their battery and has nothing to do with the wiring of my system.

I am not an electrical engineer, but this is not my first rodeo with solar. I have 4 fully functional independent systems on my ranch.

robby said:

Yep there is something up with it and they don't seem to know what it is or they are not telling.

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They obviously do know. Why would they have two battery options with the exact same specs? Only difference is the bms. EG4-LL and EG4 Lifepower are identical at their core with the exception of the BMS.

You have a 50/50 chance of purchasing the correct one for your system. If you choose the "LL" you may wind up with cell balancing issues. If you choose the "Lifepower" you may end up with pre charge resistor issues.

McRod said:

Yes, it will be a challenge to keep them equally charged. There are some additional tweeks that I can do to the wiring to help mitigate. Construct cables to equal lengths, wire directly to the bussbar, buy a Victron battery balancer... But..

I don't think I will keep the "little" Big Batteries attached as a permanent solution. Most likely, I will purchase a 3rd 200AH non-EG4 Lifepower server rack battery to couple with the system.

Click to expand...

When the positive busbar connects to your first EG4, what is the order the wire lugs are stacked in??? Does it help if you change it so the bottom lug is the second EG4 battery, and the top lug is the busbar connect? (Not sure if that's the case already or not)

robby said:

Your making it sound like putting BMS systems in Series is a good thing?

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They're simply more likely to be engineered for more current. That doesn't mean that the overall design is good.