3 Phase with Inverter backup - What to buy

I have a 3-phase 4-wire 240v power supply. I have an inverter on one phase (for lights and fans) to deal with outages.

I was thinking of getting the following accessories.
a) Power supply (will connect to inverter output)
b) 4 Reference VTs (3 for mains, 1 for inverter output)
c) 3 100A CTs (for the 3 phases)
d) 8 50A CTs (1 for inverter output, 7 for specific loads)

The 7 loads I plan to monitor are 3 air conditioners, living room, kitchen, geyser, and washing machine.

I had a few questions before I make the purchase… I am hoping one of the experienced members would be able to guide me
a. Can someone please let me know if the accessory list looks right?
b. From the docs, I can see that IoTaWatt supports 3 VTs, but would be support the 4th?
c. I would prefer the American style plug for the VTs - but will those VTs work for 240v supply?
d. Which bundle would be the best to get?
e. Anything else I may have missed, anything I should take into consideration?

I would like to monitor a few more loads in the house, and will plan to add a second IoTaWatt at a later date based on the success of the first install…

I am hoping some of the experienced members would be able to guide me a bit


IoTaWatt supports three VTs natively.

Not aware of any 240V VTs that support US style plugs. The standard US plug is specifically 120V. The VTs available from the stuff store are two-pin Euro style that will work with 240V.

The Euro bundle is probably most appropriate.

Would need to see a line drawing of how the inverter is integrated into the service in order to suggest how to monitor it. It’s possible to monitor one or both of the additional phases using derived voltage reference, so that may be the best way to do this with two or three VTs.

Thank you for the prompt reply!! I will go for the Euro Bundle as suggested

Am attaching my Main Circuit line diagram… Would appreciate any advice you have about placing the voltage reference transformer (Have numbered them in the diagram).

Oops… Plan to place the CTs and reference transformer after the mains circuit breakers, not before… Like this:

Sent you an email before I saw this. Still think you may have 120V. Aren’t those refrigerators and kitchen appliances 120V?

Regarding the inverter, I think you would just eliminate V3 and use the V4 to reference the voltage on that phase.

Thanks Bob for your prompt attention.

Am in India - with a 240v 3-phase 4-wire supply.

Agree that V4 should do, and V3 is not needed.

Have placed the order. Will post my experience for the benefit of other forum members once I get to install it.

(While we corresponded on email, wanted to post this for the benefit of other forum members!)