Any concerns if a CT accidentally covers multiphase supply?

Just starting out on my IotaWatt journey. All going well so far. Thanks for making a great device.

Now I am at the stage of working out how to optimally assign my input circuits. With that in mind I have a question about combining wires/circuits on one CT input.

When more than one wire / circuit is passing through a CT (to combine them for measurement purposes) then correct practice in a multiphase set up is to ensure all the wires passing through a CT share a phase and to use the same phase’s voltage reference. No issues with that.

But what if the wires passing through a CT were not sharing the same phase?

e.g. the wires were from from 2, or 3, of the phases of a 3-phase supply.

Aside from an obvious error in measurement, are there any concerns for risk to the IotaWatt equipment or CTs, or anything else?

My instinct just says it’s probably no big deal, it’ll just be bad data. But I’d like a second (informed) opinion.

Aside from understanding the consequences of accidentally passing wires on different phases through a CT (in my board with the jumble of wires it could accidentally happen), I also have an unusual set up where, rarely, some circuits which ordinarily share a supply phase, can have their supply phase switched.

So I wanted to understand the consequence should this occur. If it’s just going to result in a measurement error and not pose any other risk, then I’m not phased^.

^ sorry about the bad pun

As you surmised, no damage to the CT but incorrect measurement.

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Great, thank you.

It means I can safely, using derived values, free up a couple of inputs.

Somewhat related but how about if you are monitoring one phase (split in my case) with a CT in one direction and the other phase with a CT in the other direction but have them connected to the same splitter? This is for individual breaker monitoring, not mains.

I believe I’m getting accurate data since running loads on both breakers yields only positive results and IotaWatt isn’t auto reversing them anymore (since reversing one) depending on which of the breaker loads is heavier, but I’d sure like to be certain this is a good practice and won’t lead to inaccurate data.

That should be fine.