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Using 2 CT Sensors - One on Live and another on Neutral - What should be the expected Result?

Hello Everybody, New to OpenEnergy thing but have just started my first setup
I have just installed EmonTX and Paired with EmonBase.
I have installed a seperate CT sensor onto the both Live and Nutral Wire exiting the Power Meter but Before the Fuse Board.(I only did this because i had purchased two CT’s and being a rental I dont want to split the 3 core)

Currently have a very significant difference between each sensors reading in CMS as shown in the screencapture

is this a possible earth leakage or am i misunderstanging somthing?

The biulding is conjoined im not sure if this is of any relevance but just incase it might be.

Any Input would be awesome, thanks guys

I’d like to see the result at a MUCH higher power level before I’d be willing to think about earth faults or anything like that. I take it those are watts for the vertical scale, so you’re actually working below the range for which accuracy is quoted for the c.t’s you’re using. To prove it’s component tolerances or pick-up off those adjacent cables, which is the most likely explanation, try putting both c.t’s on the same cable. If the result is much the same, there’s your answer.

Can you spell out what you mean by “conjoined” (I know what the word normally means but it’s not a term we use with buildings) - and how that might that affect the electrical installation.

(@dBC - can you help?)

Are you sure that’s where your CTs are positioned? Or is one on the Live in, and the other on the Live out of the meter? The meter really only has a Neutral connection so it can measure voltage, and to power any internal electronics. I wouldn’t expect there to be any noticeable current on the meter’s Neutral connection.

Every UK meter I’ve seen has L & N in and N & L out, in that order (or 3 × L & N for a 3-phase meter) - the neutral terminals being on the same bar, and there’s usually an internal connection, often a removable link, from that to the voltage department.

We know the meter’s neutral current, roughly.
An ABB DIN-rail one: 0.8 VA, 0.2 W
An Ampy: 7.7 VA, 0.9 W
L&G: < 25 VA, < 5 W.
(all electronic meters)