Absolutely. The most likely fault here is me.
However, I have gone through everything I can think of by way of proof.
Just tried a test of setting the set point on the ESS to 3kW.
The physical grid meter (well the in-home display part) reads 1500W.
I am running an external system logging to MariaDB, it pulls the data from the registers in the Cerbo…. and again all the demand readings are around half that which I would expect. (Annoyingly, it uses that to forcast tomorrow’s demand, which it will now think is half as much as expected - but that is a trivial problem to fix)
Image above is with a grid target of 3000W set in the Cerbo. The load should be around 3kW at this time… again, that displayed is about half.
For clarity, it isn’t simply that all the values are half… I think some are double… which almost certainly comes from a derived value being based on an incorrect measurement.
In theory, I could swap the units around, but would have to physically move them so that the CT wiring was on the right unit.
My present thought - and it is no more than that - is maybe an internal CT has failed. It seems to measure correctly from the external CT (proved when in passthrough), but just wondering if an internal measurement is ‘wrong’. It is however extremely unlikely to die just as I add a parallel unit.
I suppose I could prove that by setting the unit back up as a single.