Odd 'plant' behaviour.

Folks
I've operated my plant for nearly 3 years now - more or less successfully. As you'll all be aware, one gets to know one's own kit pretty well during that time - along with all its foibles, and how to overcome them.
I have two AC 3.0s, each with its own 8.2 battery. I control them with Home Assistant.

Strange behaviour this morning...
They were set to charge as usual 04:00 - 07:00 to coincide with our Octopus Cosy tariff.
One battery got charged to 100% (correctly) as usual, the other didn't - although charge had been set to 'Enable' and 3kW on both inverters.
Try as I might, I couldn't get the errant combo to charge.
I now have another issue with the errant inverter - whatever figure I set to discharge at, it just dumbly discharges at that rate - whether there's a corresponding house load or not. If there's spare discharge power, it'll cross-charge to the other inverter, and if I set that one to not charge, the balance just discharges to grid.
I've tried re-setting everything (including disabling the GiVTCP in Home Assistant), re-started both inverters several times, and even re-started the errant inverter's battery, but to no avail.

Giv helpdesk say poss several days before I'll get a call back!

Any thoughts?

TIA.

Sykes Any errors in the Givenergy portal?

It rather sounds like a problem with the CT clamp. Check that the CT clamp breaker hasn't tripped off, and if you can, power it off and on again

Otherwise a reset to defaults in the portal?

I'm disappointed. I thought this was going to be a story of some errant rubber plant running amok or perhaps the awakening of a triffid species!

Hi Geoffrey
Thanks for the reply.
I think if it were a CT, then I'd expect to see the same behaviour on both sets, not just one (although this one is designated as the slave).
I've never heard of a CT clamp breaker, but I've checked all of the associated breakers, and none have tripped.
I've also done a default reset in the portal, as well as powering the inverter AND associated battery fully down, and back.

The next Octopus window's come around, and whilst the good inverter's allowing its associated battery to charge, the errant one's still playing up.
I think it's pointing more to an inverter fault, but I'm living in hope...

Thanks again.

killythebid
It probably would have been easier to deal with!

Sykes I think if it were a CT, then I'd expect to see the same behaviour on both sets, not just one (although this one is designated as the slave).
I've never heard of a CT clamp breaker, but I've checked all of the associated breakers, and none have tripped.

I am confused by your setup. You said you have a plant setup, then describe having two AC3's each with their own battery. That is what I know as a plant setup.

So if you have such a plant setup then each AC3 is completely independent, has its own EM115 and CT clamp and there's no master/slave relationship. If there were then there wouldn't be half the problems with cross charging and needing the development of the EMS.

Having said that I think it is possible to wire multiple devices to a single EM115, so maybe that's what you have? Its just not the way my plant is wired up.
I have two EM115's in a small circuit box on their own, with a power breaker for each. I have once had one trip which is why I was suggesting that.

You could try swapping the battery cables between your two inverters to see if that narrows down the problem.

The other idea I had was to check the cable for the EM115 where it goes into the bottom of your inverter, check that it is correctly seated in the socket. Certainly on my Gen 1 hybrid they don't have proper click in place plugs and they can come loose.

Hi Geoffrey
GE have always referred to my installation as a plant - hence my terminology.
I have two CTs, but one is for my myenergi kit (zappi and associated gubbins) so there's only one which feeds the GE stuff. There's also only one EM115, and the inverters are set up as master/slave.
I've checked all the wiring, which seems to be all intact.

I'm not sure whether the battery cables will reach, in order to try and transpose the issue; I might have to resort to that, if I keep coming up with blanks.

I've made a bit of progress today, in that I've managed to force-charge the errant combo during a cheaper Cosy slot. I did some more fault-finding, and tried other ways to reset the inverter's logic, and start with non-clogged registers. At first, I wasn't at all convinced, but having charged the battery fully, and the inverter now seemingly discharging on-demand (playing nicely with its partner) it seems that things are getting back to normal.

I remain sceptical (don't believe in serendipity, when it comes to electronics), but with some hope...

Thanks for your help thus far.

Sykes