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Limited charging current after adding EG4 LL battery

3fordasho

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I have a pair of Growatt 5000 es inverters operating in parallel charging 5 EG4 LiFepower4 batteries, a 4500w PV array feeding one inverter and a 3550w array feeding the other. Battery charging was ok and up to 2600watts or more per inverter while also supporting loads.

I then added a 6th battery which is the EG4 LL version. Since adding the LL battery both inverters limit output charge to ~1360 watts, nothing more. I've since added 3 more LiFepower4 batteries and still have charge power limited to 1360 watts per inverter. Needless to say all 9 batteries are not reaching full charge on many days where as before the charging was easily completed by noon.

Any help would be appreciated!

Yes I've contacted SS but have been waiting for tech support to get back to me.
 
Sounds like a communication problem. Did you change the primary battery? Maybe try switching back.
 
Well, being you have Growatt inverters, I assume you are using the BMS communication cables. If so, hate to deliver the bad news, but the EG4 LifePower4 and EG4 LL batteries BMS communications are not compatible with each other. SO while your new EG4 LL should work fine in the parallel with the LifePower4, you won't be able to have it hooked in with the BMS communications.

Just making the assumption you are trying to utilize the battery communication port on the LL.. If not maybe something else is going on.
 
That's what I am assuming.
Probably should just take the LL's off the communications. And just let them run as dumb batteries.
 
Well, being you have Growatt inverters, I assume you are using the BMS communication cables. If so, hate to deliver the bad news, but the EG4 LifePower4 and EG4 LL batteries BMS communications are not compatible with each other. SO while your new EG4 LL should work fine in the parallel with the LifePower4, you won't be able to have it hooked in with the BMS communications.

Just making the assumption you are trying to utilize the battery communication port on the LL.. If not maybe something else is going on.
Yes I am using the BMS communication. I was assured they were compatible but I've had multiple problems getting them to work together so obviously they are not. They are working together now except for the limited charging. I am going to pull the LL from the system and just use the Lifepower4 batteries.
 
It hurts my head why Signature Solar would release 2 identically sized battery packs of the same spec, both able to communicate with Growatt inverters and not make the BMS communications between them compatible with each other... It's just poor engineering and production planning.....
 
Last night I unplugged the communication cable to the LL battery but left it turned on (it was the last in the chain). Did not shut down system. Today there is plenty of PV power available but my charge rate will not go above ~1360 watts. PV output is the 1360+house loads no matter what. If house loads go up the PV output goes up but the 1360w to batteries stays consistent. Both inverters do the same thing. Tonight I will completely shut down the system and bring it back up - hoping that will reset.
 

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That was going to be the next suggestion.
Hopefully it works.

Success! after removing the LL battery from the communication string AND a complete restart of the system both my inverters are charging close to 3000w ea. So I guess I'll have to use the LL battery as a dumb battery with no communication to the other batteries.

As a FYI I tried the LL battery as the master as the tech at SS said to do, and also tried it as the last battery in the communication string - didn't matter - if the LL battery is in the communication string it limits both inverters to 1360 watts each charge power no matter what the PV arrays can produce.



Is there any downside to using the LL battery in this fashion? (other than the reason for having the display on it was to monitor the entire bank SOC and now it only tells me the LL battery SOC)
 
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Awesome
You are still going to get an idea of the entire banks soc from that screen. The batteries in parallel will equalize with each other. I also plan on using 1 LL as the last battery to do this. The rest of my bank are non LL.
 
other than the reason for having the display on it was to monitor the entire bank SOC and now it only tells me the LL battery SOC)
I don't think the LL would have showed your entire bank of batteries SOC on display, just it's on SOC. In fact NONE of the EG4 batteries communicate with each other, but rather the master will poll the other batteries and send all of the batteries data to the inverter. Another words, each battery doesn't know anything about the other battery when hooked together, the master battery polls and forwards only.

In your application "using growatt inverters to communicate with batteries", it does suck that the LL can't communicate with LifePower4 to the Growatt. I don't know the specifics of why, but have been told by signature solar they do NOT share the same BMS, so that would probably have a lot to do with.

If I was selling rack batteries I'd make damn sure they all could work together and talk to at least the inverters I ALSO sell. VERY POOR product engineering and planning on Signature Solar's part. The more I deal and talk with them, the more I've come to the conclusion, they are simply China importers. They don't make anything or even spec anything it seems.

Good news is the EG4 LL does share the same cells "I've been told" and is of the same capacity, so it should fit in nicely and work fine with the LifePower4 batteries in parallel. Your inverter just want be able to monitor it's SOC and voltages, but you do have a display to check them and they should follow LifePower4 very closely.
 
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Thanks for everyone's help! got more tech support here in a matter of minutes than...


Nice sunny day, both inverters now charging over 3500w each. Already the bank SOC is almost at what it took all day yesterday to reach.
 
You could use something like Solar Assistant to pull all of the battery information from both types and put them into a single screen.
The BMS's are completely different between the 2 types, so I'm not surprised they don't talk to each other.
 
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