GivTcP battery charge rate keep changing / correcting itself

3 comments started 2026-04-17 last 2026-04-18
Home Automation
L
#1 lam22

Hi

After dabbling in this for a few months, setting up HA in anger now due to recent events, after following the excellent new guide from Speak to the Geek.

I'm keeping my charge rates down to about 2/3rds on my Gen 2 Hybrid but I'm seeing consistently the charge rate going back up to maximum every 30 / 60 mins or so, only for it to correct itself a few minutes later.

I'm on Octopus Go - no external API control of the inverter.

Anyone else seen this before?

#2 hoggy

Do you have more than 1 battery? And is one of them a 5.2kWh battery?
The charge power is a (sort of) complicated mess based on how big the batteries are - sounds like the inverter is losing Comms with one of the batteries and then finding it again. Might be a loose connection on the BMS cabling somewhere
(2667 is a rather suspicious value that happens to match the max power you can set on a Gen 2 if it only has a single 5.2 battery on it)

L
#3 lam22

hoggy 2 x 9.5 batteries. 2667 was actually a random number I happen to put in.

Playing around with this a bit, I think it's something to do with charge rate vs charge rate AC. Maybe everyone knows this already but it looks like charge rate AC (the percent value) is really just a percent of the charge rate. e.g. setting both results in an unholy mess but having charge rate set to max, and only the AC value lower 'seems' to be behaving itself.