Pylontech SOC

[drjim]

I have a stack of 4x US2000 and 2x US2000C. All wired together with the newer of the 2000C as the master. Comms cables between batteries. Positive and negative to inverter from opposite ends. Running off my shed roof solar on a growatt sph4600. Sun ran away when I got it wired up at the end of May so had very poor solar days since I turned on, very rarely getting to full charge unless I charge from grid.

One of the US2000 drops charge quicker than the others, biggest issue is the second us2000C keeps dropping its SOC so at the moment it says 16% whereas the stack overall is 31%. This is displayed in solar assistant.

I managed to find pylontech batteryview and downloaded it - looks a fairly old version (3.0.37) or it just looks like old software when you run it! All the cells are showing similar voltages, just this US2000C doesn't seem to charge up as much as the others, and when it does it then discharges a lot.

I did have an alarm beeping not long after I set things up, but there are no alarm codes showing on this battery. Need an RJ11 adapter to connect to the US2000 packs. I had assumed as they all talked to each other via CAN the batteryview would see the whole stack, clearly not!

Solar assistant doesn't seem to let me tinker with battery charge voltage settings in the inverter, but I can see it says recommended charge voltage 53.3 and 25A which should be right fo rthe pylons - clearly the battery comms are working.

I was wondering about pulling the 2000C out of the stack and trickle charging it with a suitable charger. Anyone have any suggestions - either what else to do or on a suitable charger??

Ta

Jim

[Stinsy]

Pylontech batteries have VERY slow balancers that only work at the top end. It is therefore a good idea to keep them at 100% for a few hours every day. That should be no problem at all this time of year!

[drjim]

Problem is I only have 2.4kwp connected and it's cloudy in manchester!

Did have 2kw of old badly oriented shaded panels on second MPPT but for some reason the voltage/current on MPPT2 was chopping up and down taking MPPT1 down with it, only happened a couple of times but I've stuck those on my old inverter where they worked fine. I have 6 x 450w DMEGC bifacials that City plumbing delivered on Friday, have a westerly facing walll they are going vertically on for afternoon/evening sun. Price to install on roof isn't really cost effective for this DIY project. Had a quote and they reckon they can only fit 6 panels on that side of the roof with 5 on the other side of the ridge. That's what I can do with existing shed and new wall panels for a fraction of the cost.

I'll just leave it in battery first mode for a day or two to get them topped up, all being well!

[Stinsy]

Problem is I only have 2.4kwp connected and it's cloudy in manchester!

Did have 2kw of old badly oriented shaded panels on second MPPT but for some reason the voltage/current on MPPT2 was chopping up and down taking MPPT1 down with it, only happened a couple of times but I've stuck those on my old inverter where they worked fine. I have 6 x 450w DMEGC bifacials that City plumbing delivered on Friday, have a westerly facing walll they are going vertically on for afternoon/evening sun. Price to install on roof isn't really cost effective for this DIY project. Had a quote and they reckon they can only fit 6 panels on that side of the roof with 5 on the other side of the ridge. That's what I can do with existing shed and new wall panels for a fraction of the cost.

I'll just leave it in battery first mode for a day or two to get them topped up, all being well!

It's going to be sunny tomorrow. Lay your new panels on the lawn and hook 'em up!

[drjim]

A tempting idea!

I gave them a tickle from the mains...



Sadly I have to go to work tomorrow so I think the new panels will have to stay in the shade for now.