Growatt 24V and SOK battery issue

[dsheehy]

Hi all,
I have a 24V Growatt SPF 3000TL LVM with 1400 watt panels (2S2P) and 2 SOK 100Ah 24V batteries in parallel. I've had this setup running for about 2-3 weeks with only some minor issues where the inverter flips on and off at sunset/sunrise sometimes. At dawn I woke up to 3 beeps and then all power went out. I can't get the Growatt to turn back on. Batteries are reading 0.78V and none of my DC appliances will turn on, so I'm assuming they went into a protection mode by the BMS. I don't know how they could have discharged so rapidly overnight as I was at 28.2V yesterday and only run a dometic fridge, starlink, and a few fans overnight. I also have the ability to sent grid power to it but it won't turn on with the grid power either. I'm pretty new to this so stumped where to look next but it looks like I have 2 issues, low voltage batteries and something internal on the Growatt. Is the only way to reboot the Growatt to turn off all other power sources and boot it with the batteries? If so, then the low voltage batteries are likely my issue I'm thinking.

Side note: we have tons of sun here today and I should already be able to run the Growatt with the batteries off, but nothing is happening.

Thanks in advance,
-Daniel

 

[DThames]

I have some of the same model Growatt units. I think the battery is required for any of it to work.

I am no familiar with the SOK but I am guessing you have no way, no Bluetooth, to access the battery BMS and see what is going on. Is that correct?

I would try to connect a charger to the battery and see if you can get the voltage back up, or get it back on somehow.

Also with the problem battery(s) disconnected, do you have any other 24v battery that you can connect and test the Growatt? i don't mean test charging nor test inverter output, but just see if the display will come on, make sure you can look at the settings, etc.

 

[dsheehy]

I don't have a 24V battery charger, but just ordered one, and I don't have another 24V battery, so I'm heading out today to rectify that. Will report back once it's up again.

 

[DThames]

I don't have a 24V battery charger, but just ordered one, and I don't have another 24V battery, so I'm heading out today to rectify that. Will report back once it's up again.

A couple of small SLA 12v in series should work to boot the unit.