EG4 18K PV can you use "dual sets" of CT's

[youngfg]

My existing wiring has two 200 amp feeds coming out of my utility meter, one to my shop and one to the house.
I will have the inverter powering the house and I want to setup zero export, so I need to measure both of the 200 amp feeds.
It would make the wiring much easier if there was a way to use two sets of CT's to the inverter, one set of CT's for each 200 amp feed.
I see that there is only one CT port on the inverter, is there a way wire another set of CT's?
Or can I get a CT that is big enough to run two 4/0 wires through? I could put the big CT's right at the bottom of the meter where both wires connect.
Otherwise I have to rewire all my panels to get all the grid power through one set of wires.

 

[timselectric]

My existing wiring has two 200 amp feeds coming out of my utility meter, one to my shop and one to the house.
I will have the inverter powering the house and I want to setup zero export, so I need to measure both of the 200 amp feeds.
It would make the wiring much easier if there was a way to use two sets of CT's to the inverter, one set of CT's for each 200 amp feed.
I see that there is only one CT port on the inverter, is there a way wire another set of CT's?

No, but it wouldn't provide the correct measurements anyway.

Or can I get a CT that is big enough to run two 4/0 wires through? I could put the big CT's right at the bottom of the meter where both wires connect.

This is the proper way.
And yes, they are readily available. You just have to find ones that would be compatible. (Right ratio)

 

[timselectric]

This is just an example, not a recommendation for this specific product.

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[mciholas]

You can take two CTs and combine them into one CT input port. See:

Putting CTs in Parallel - multiple CTs on one port | Schneider Electric USA

And also:

How to Parallel Current Transformers? – Voltage Disturbance

Basically, CTs are current ratios, so the current from the two CTs add together into the sense resistor of the inverter.

The CTs have to be of the same type, be on the same phase, and be oriented properly.

I have not tried this personally, but it seems like it would a reasonably simple thing to try.

Putting both feeds through one larger CT obviously will work, too.

Mike C.