Metering when critical load connected to Backup AC?

[ChrisJEvans]

The schematic below is based on Easy-PV's default suggestion and seems a common arrangement. I've added connection to critical load from the Backup
AC.
If there is no Backup AC connection then the position of the 'PV meter' makes sense to me, but to my mind adding critical load to the Backup AC connection really messes up the 'PV meter' e.g. when no PV supply so the grid is supplying the 'critical load' the meter would be 'importing' and when PV is supplying the critical load the meter will be being bypassed.

Also whilst it's unlikely to happen, presumably if the inverter is removed or fails by stopping grid supply to the critical load then 'critical load' will be up creak without paddle. Is there a simple way round that? e.g. a manual source switch over?

Do modern Inverters like the Solis supply via the network connection all the information you need? making the PV meter useless. It would be nice to be able to monitor PV output in real time.

or have I misunderstood things?

Wagner renewables have supplied a Emlite Total Generation Meter ECA2Z
I'm still trying to source my Hybrid Inverter. Probably a Solis RHI-3.6K-48ES-5G or RHI-6K-48ES-5G
15 x JA SOLAR 385W JAM60S20MR
2 x Pylon US2000 or US3000 when I can get them!



p.s. Is there a way of attaching a PDF to a posting?

[Oldgreybeard]

Easy to add switching to the critical load consumer unit, so that it runs either from grid power or backup power. I did this with a 16A contactor that has two normally open poles and two normally closed poles. The contactor coil is power by the emergency supply from the inverter, so with no emergency supply present the essential loads consumer unit is powered from the grid, with the emergency supply present the contactor energises and switches the power to the essential loads consumer unit to run from the emergency supply.

I just followed the diagram in the Sofar manual (although I opted to use a DIN rail mount contactor so it would fit at one end of the consumer unit):

sofar EPS.jpg (63.61 KiB) Viewed 437 times