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Not charging to 100%

That Nasally Guy

New Member
Joined
May 31, 2023
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7
Location
Kentucky
I have an EG4 3000w 48v 3n1 inverter/charger and two 5kw Rubix 5kw batteries. When I first wired the system up to my bus I was charging the batteries with a small Pedator inverter generator. The batteries would charge up to about 92% (with about 5-6 amps coming in from the generator) before the amps in would be cut to zero by the EG4. I changed a setting in the EG4 so that it would send 9-11 amps from the generator. The batteries would charge faster but then the EG4 would quit sending current to the batteries at about 82% capacity. Then I got my panels set up (eight 380W in series) and they're making good power - I've seen up to 25A going into the batteries but now the EG4 cuts current in at 70%. Why is this? I talked to the Amish guy I bought the system from and he kind of explained it but I'm skeptical. Also, I have a friend with an EG4 controller/inverter with EG4 batteries and he said when he connected the comm cables from the batterites to the charger/inverter it automatically changed a buch of settings and he sees 99-100% capacity all the time. I currently don't have any comm cables between my charger and batteries because the Amish guy said I didn't need them and the cables that came with the system don't have the proper jacks (I think) to go between the two.

Should I set the original setting back down (slower charging but higher capacity)?
Should I get the correct cables and let the charger and batteries talk to each other?

My batteries have RS485/CAN, RS232, and RS485/RS485 jacks that look like CAT5 phone/computer jacks. The EG4 has an RS485 that looks like printer USB cable jack and an RS232 that looks like a CAT5.

Maybe one of the short gray cables on the right f(see attached image) from battery to battery and the gray cable w/yellow jacks on the ottom left from EG$4to batteries?

Any thoughts/help?
 

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EG4 are not particularly reliable when charging with traditional generators. This is the reason the Chargeverter exists. They seem to work okay with inverter generators, but I tend to be skeptical.

Worth noting that the SoC computation is iterative and only accurate after the battery has been fully charged and balanced.

What is your absorption voltage? Recommend 3.45-3.55V/cell
What is your float voltage? Recommend 3.375V/cell if the battery is balanced, 3.40V/cell if the battery needs additional balance time.

Generally, float should not be engaged with a generator as it's wasteful
 
EG4 are not particularly reliable when charging with traditional generators. This is the reason the Chargeverter exists. They seem to work okay with inverter generators, but I tend to be skeptical.

Worth noting that the SoC computation is iterative and only accurate after the battery has been fully charged and balanced.

What is your absorption voltage? Recommend 3.45-3.55V/cell
What is your float voltage? Recommend 3.375V/cell if the battery is balanced, 3.40V/cell if the battery needs additional balance time.

Generally, float should not be engaged with a generator as it's wasteful
Thanks for the reply. Sorry for the late response but I live off grid and don't have internet access until I come into town. I looked at the user manuals for both the EG4 and the Rubix batteries and did not see where could check absorption voltage. Please keep in mind that I'm a complete noob so I could have missed it. I did see floating charging setting on the eg4 and I saw some battery equalization settings too (see attached images) I did notice that the SoC on one battery is 57% and the other is 66% (unbalanced?). Also, on the batteries under an SoC setting there is an FCC that is currently at 102.3AH. Relevant? Thanks for the help.
 

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