EG4 Chargeverter - Any concerns with charging and pulling from batteries at the same time

[NopeNobody]

So have a noob question on the EG4 Chargeverter.

Should I have any concerns with charging and pulling from Eg4/SOK/Trophy batteries at the same time? The chargeverter would be charging via generator and a TBD inverter would be pulling (possibly Victron, EG4, etc).

 

[42OhmsPA]

So have a noob question on the EG4 Chargeverter.

Should I have any concerns with charging and pulling from Eg4/SOK/Trophy batteries at the same time? The chargeverter would be charging via generator and a TBD inverter would be pulling (possibly Victron, EG4, etc).

Nope None
Ps, read through the chargeverter thread, this was covered many pages ago.
You can charge with your panels and pull from the batteries at the same time, can't you?

 

[Gavin Stone]

This is a good question. I actually wondered this same thing when I first started learning about solar. And no, there isn’t any issue. It’s the same as running more then one solar charge controller to the same battery bank.

 

[MySolarAddiction]

Doing it right now.... not a problem.

 

[Smack3]

I just bought an EV4 chargeverter and waiting for delivery. in the meantime I called signature solar about this exact question. I was told by the tech that I should only charge batteries with the inverter off, so I pressed him asking about separate charge controllers basically doing the same thing. I have my separate solar charge controller set to turn off at a lower voltage so it does not interfere with the primary inverter (growatt 8k) ability to manage the batteries. After arguing with him about that, he spoke to another senior tech who also said not to do it. I told him it totally defeats the reason I bought it, which is to top off my batteries on winter days with short days no sun. I don’t want to switch my loads to street power just so I can charge my batteries. none of the YT videos I have watched address this seemingly common question. he said something about batteries can only charge or discharge, but not at the same time. Isn’t that what the BMS job is, to figure out which mode is needed?

i have 6 EG4 batteries connected to growatt 8k as primary inverter with 2.3k watt solar panel and a spare growatt 3k 1.6k watt solar being used only as a charge controller.

 

[HighTechLab]

It's fine to do both at once.

The tech is somewhat right; you can't charge and discharge a battery at once. That's because the charge current goes straight to the loads and cancels out.

You can't have current flowing down the same conductor in two directions at once.

For example, if you have 50A of charge current available, and 25 amps of loads, then the battery is not charging and discharging. Simply, 25A of charge current goes to the loads and the remaining 25A of current goes to the battery. At that point in time, the battery is only charging, at a rate of 25A. Nothing stops you from running both devices at once...

For further reading, google Kirchoff's Current Law.


The only caveat: if you are running multiple chargers at once, you could possible exceed the maximum amount of charge a battery can take. In that case, the BMS will intervene to prevent overcurrent...but you have to be exceeding the limits of the battery for this to present any trouble.

 

[Browse]

That is the way I have my 12k Growatt set up but it's only for emergency backup power. During normal outages where there is no need for the 4 ton HVAC unit, we can run on batteries for most of the day, recharging the rack with the generator connected for a few hours. On hot days when the whole house HVAC is needed, the generator powers the Chargeverter, keeping the battery rack SOC high while the Growatt powers the house. The generator alone can't handle the HVAC startup surge, so we use the Chargeverter as the "middle man", providing the DC voltage directly to the rack.

 

[MySolarAddiction]

It's fine to do both at once.

The tech is somewhat right; you can't charge and discharge a battery at once. That's because the charge current goes straight to the loads and cancels out.

You can't have current flowing down the same conductor in two directions at once.

For example, if you have 50A of charge current available, and 25 amps of loads, then the battery is not charging and discharging. Simply, 25A of charge current goes to the loads and the remaining 25A of current goes to the battery. At that point in time, the battery is only charging, at a rate of 25A. Nothing stops you from running both devices at once...

For further reading, google Kirchoff's Current Law.


The only caveat: if you are running multiple chargers at once, you could possible exceed the maximum amount of charge a battery can take. In that case, the BMS will intervene to prevent overcurrent...but you have to be exceeding the limits of the battery for this to present any trouble.

Xackly ??

 

[42OhmsPA]

It's fine to do both at once.

The tech is somewhat right; you can't charge and discharge a battery at once. That's because the charge current goes straight to the loads and cancels out.

You can't have current flowing down the same conductor in two directions at once.

For example, if you have 50A of charge current available, and 25 amps of loads, then the battery is not charging and discharging. Simply, 25A of charge current goes to the loads and the remaining 25A of current goes to the battery. At that point in time, the battery is only charging, at a rate of 25A. Nothing stops you from running both devices at once...

For further reading, google Kirchoff's Current Law.


The only caveat: if you are running multiple chargers at once, you could possible exceed the maximum amount of charge a battery can take. In that case, the BMS will intervene to prevent overcurrent...but you have to be exceeding the limits of the battery for this to present any trouble.

Couldn't have said it better!

Just add more batteries so you don't have to worry about exceeding max charge current, it's the only logical solution. ?

 

[Smack3]

It's fine to do both at once.

The tech is somewhat right; you can't charge and discharge a battery at once. That's because the charge current goes straight to the loads and cancels out.

You can't have current flowing down the same conductor in two directions at once.

For example, if you have 50A of charge current available, and 25 amps of loads, then the battery is not charging and discharging. Simply, 25A of charge current goes to the loads and the remaining 25A of current goes to the battery. At that point in time, the battery is only charging, at a rate of 25A. Nothing stops you from running both devices at once...

For further reading, google Kirchoff's Current Law.


The only caveat: if you are running multiple chargers at once, you could possible exceed the maximum amount of charge a battery can take. In that case, the BMS will intervene to prevent overcurrent...but you have to be exceeding the limits of the battery for this to present any trouble.

Thanks for the quick response and thorough explanation. It makes total sense to me. still Curious why signature solar did not explain it that way. It isn’t practicable for anyone to shut down their inverter just to charge your batteries. I am happy there habe been so many confirmations about this topic. I was going to disappointed if i couldn’t just top off batteries whenever needed by starting my generator and letting it run for a few hours. I have a generator connected to natural gas which should be nice to not have to deal with fuel.now I just need to patiently wait until it is delivered some time in January , I hope.

 

[LydMekk]

Doing it here. Nice parallel feature pulling from the batts to the inverters while battery tender from the net.
Works perfectly.