Need help with MPPT LV6048 , not charging Eg4 rack batteries

[Kennstx4242]

I have 2 MPPT LV6048 set up in parallel 240v off grid with 6 -100AH 48Volt Eg4 rack batteries. I also have 7500 watts of solar panels, plenty of sun Marana AZ. It has been set up since January 2023 and worked flawlessly. All of a sudden it will not charge the batteries all the way up. Every morning it in alarm status and nothing has changed in my electric use. I have reset the batteries and the inverters all the time and it never changes anything. I haven’t changed the settings since set up. I want to know shouldn’t the batteries go up to 56-57 volt? They only reach 54. Before I never had any problems with them and can’t figure what is wrong with them. Does anyone have any suggestions ? I would appreciate it! I’m trying to learn all this Solar stuff. Thank you

 

[BentleyJ]

Can you fill in some missing information and clarify.
1) Alarm in the morning? Are you referring to a low battery voltage alarm because the batteries didn't get charged up during the previous day. Or are you referring to a high voltage alarm because you are trying to charge the batteries at night with utility power via the Inverter/Charger.
2) What alarm, on the inverter or batteries or both? What is the fault code?
3) Just because you didn't change any of the settings doesn't mean they are still the same as before. Electronics are not perfect. I got locked out of my Schneider Combox the other day because the admin password got corrupted somehow. Had to reset back to factory settings and then re-enter everything to the proper values. Would suggest you scroll through ALL the menu settings on the inverters and batteries.

 

[Kennstx4242]

The alarm light is on the batteries. The inverter’s never had any issues yet. I haven’t received any fault codes on inverters. Just looked at batteries didn’t even charge 50 percent yet and normally around 75 percent by 2:00 pm Arizona time. Still full sun out. I will go over all the settings on inverters. Already reset batteries. Thanks for suggestion.

 

[OffGridForGood]

@Kennstx4242 - I also use the MPP 6048 model, hope to be able to offer some help:
First thing that comes to mind, the 6048 has lower PV input voltage than many modern Inverters, only 145v, and this is a hard limit.
I find mine work best with the PV at 90v nominal - leaving room for the MPP function to ramp voltage up or down a bit.
Any chance your system is going higher than this on the PV input ?

 

[Kennstx4242]

I actually had that problem last year when it was set up. Had way to many volts, since then its been hovering around 70-90s during full sun. Other wise everything was good until now. Haven't had any fault codes on the inverters yet. Thanks for suggestion.

 

[OffGridForGood]

With the PV voltage confirmed, and no Inverter faults showing, next lets check the settings for the charge profile. You noted lower voltage than expected in the OP.
The MPP 6048 settings are not factory set for LiFePO4, the default setting is for AGM, and they have option for Flooded Lead Acid, the third option is User-defined settings. This is set in Program 05. Once this is set, you then need to also set:
Program 26 Bulk/Absorb voltage (I use 56.0, Will recommends 56-58) check the EG4 manual for recommendation
Program 27 Float Charge voltage (I use 54.4, same as Will recommends) check EG4 manual for recommendation
Program 29 Low voltage cut off (I use 48v) Will recommends between 42-48 and your EG4 manual likely suggests a setting.

Also Check: Program setting 02 Maximum charging current. This can be set in 10A steps anywhere from 20A to 220A, IIRC the default is only 20A.
With 7500W you will need a setting of at least 100Amp in program 02.
Not sure how you split up the 7500W of PV you have between the two inverters and two MPP's on each inverter (four inputs).
7500 / 80v =94Amps (too much for a single MPP input on the 6048, which is limited to 4000 per input.
The manual indicates using MPP input #1 first, then #2, It doesn't say what to do with two inverters, but I connected #1 on both first, later when I added more PV then I used MPP input #2 on each inverter.

check over your setttings, hope some of this helps.