Monitoring of two buildings with solar in North America

I think I get the picture now. On the face of it, it seems a fairly straightforward scheme.

Firstly, you probably don’t need 200 A c.t’s for the two main incomers (service entrance wires).
Bill has written about this many times, basically you need to determine the kVA rating of the transformer feeding your property, and hence the maximum current that it can deliver. That will be less than the cable rating: More info here: US 200 Amp Service explained or Do I need a 200 Amp CT?
You should also check the maximum load you anticipate.

One problem I do see is where you monitor your voltage. For the main panels, it’s obviously the mains, but for the critical loads, you need to measure the inverter voltage.

Is it possible to move the c.t’s around?
If you move the House Critical Loads c.t’s to the other end of the 50 m cable, you can have those plus the Shop Critical Loads c.t’s working into one emonTx Shield and using the inverter voltage to compute real power.

If you move the Shop Main Panel c.t’s also to the other end of the cable, on the outgoing side of the Disconnect, you can have those plus the House Main Panel c.t’s working into one emonTx Shield and using the mains voltage to compute real power.

Two points remaining:
Would you want to measure independently the Critical Loads power when fed from the mains?
And if you can’t talk via Modbus to the Inverters and you want to know their individual outputs, then you need a third EmonTx Shield for that. Otherwise, you have the total inverter output already from the sum of the two infeeds.

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