Solar PV battery options

From your log "Output short circuit protection" points to where the problem is. Did you double check the connection from your P connectors on your Seplos to the positive terminal on your ME3000SP? Is all good and tight? I presume you also have a fuse in that circuit as you should do?

What sort of load was on your ME3000SP early this morning?

Is the Seplos capable of working with a shunt? That would give you a very accurate SOC. I have one on my BMS (don't have a Seplos though) and the shunt measures the exact amount of kWh that is going in and out of the battery. So once you have fully charged and balanced, that is your 100%, everything from there is measured by the shunt for the SOC. But the BMS still protects the cells by keeping an eye on the voltages.

Thanks for this, I set everything up and wired the battery as you said and now there's an error in the Sofar a high battery temp warning of -21C.....wtf.

I've tried a couple of time to reset it by powering it off and leaving it for a while but the error still persists.

I'm gonna try and update the Sofar firmware tomorrow to a later version as I'm on 3.0. Is there a common version that people use or is it better to raise this with Sofar support ?

Oops pressed post too soon.

I wonder if it's feasible to set this up without a bms connection to the sofar inverter...does that even make sense

It seems that Seplos and most of China will be on holidays until the 30 of January so I might be waiting a while for some response from them.

I've read conflicting information that the RJ45-RJ10 CANBUS cable from Sofar to Seplos needs to be modified so that only pins 4 & 5 are used.

Is this correct?

So I cut the cable as an experiment and it seems to have fixed the issues. The seplos is no longer going into shutdown and the battery back seems to be charging and discharging. I'm still occasionally getting a "The power grid frequency is too low" error in the Sofar but that may be an intermittent thing that I'll contact Sofar to fix.

So good so far, I'll keep an eye on it during the day and hopefully it settles down and I can forget about it ;-)

I very much appreciate all your help so far and hopefully I'll stop bugging you now.

Fantastic outcome, and great knowledge sharing

yep I had set it to the Ireland code but then set it back to generic European (as per the sofar manual to fix the issue). I'll keep it there for a while to keep things stable and then move back to Ireland

I don't have one of those inverters but I think your only options are the two brands you mention. Definitely not worth the extra money.

You could forget about using the Huawei with a battery and get a ME3000SP or similar plus suitable batteries (DIY if you can) for a lot less money.

My installation is coming up next month. I ordered 16 X 380w panels totalling 6.0KWp, 1 X Solis 5G Hybrid Inverter and 1 X Dyness 4.8KWH battery.

I started having second thoughts on the battery purely from the cost perspective (it's €4400). I can source a Dyness 5.1KWH battery online for €1700 including delivery. In fact, I was tempted to cancel the battery from the original order and order 2 X Dyness 5.1 batteries separately.

The issue I have is the supplier will only install the Solis Hybrid Inverter if I order the battery from them. Otherwise, they install the standard inverter. So my dilemma is that I would need to replace the Inverter and the outlay of the battery cost after the installation if I want to source the batteries myself.

I'm new to this, so don't think I'd venture down the DIY route just yet. Maybe later if/when I add more panels.

Any advice is appreciated.

Ordered in September and paid deposit. It will be end of February for installation. They will remove the battery cost from the bill, but this means installing a regular inverter.

What is approx cost of Solis Hybrid?