Monitoring voltage between neutral and earth

D103 single-phase connection

The D103 energy monitor is essentially 3-line. Therefore, it can be installed in a single-phase power for monitoring lines to different consumers (boiler, air conditioning, kitchen, sockets, lighting, etc.)

Connect current transformers and put on the appropriate lines that go to consumers.

Connect voltage to one of the inputs and set jumpers for the remaining power inputs L1 l2 L3.

On the terminal block, can I connect the following connections:

N   Neutral

L1 240AC phase

L2 Earth?

Will that make it possible to monitor voltage between Neutral and Earth if I monitor L2?

In general, the voltage between Neutral and GND should be early zero (maximum 20V)
Why measure it at all?

Yes, it should  be zero, but it's not necessarily so. I would like to monitor it because if it's more than 4Vac, it will disconnect the inverters of the photovoltaic system I have, in which case I have to report it to the energy provider. Surely, if L1, L2 and L3 are isolated then I connect the earth to an unused L2 or L3, then I should be able to monitor this voltage? Of course you know the internal circuitry of the device, hence why I am asking. 

Theoretically, you can connect GND to input N.

If you need to follow one line, then you can use the 1-line D101

If I connect Ground to input N, how will I be able to monitor Ground to Neutral voltage?

Sorry, the D101 will not work, since the energy monitor needs 240Vac for power supply.

Apologies to insist :) I have the D103. Can I connect as follows:

N:  Neutral

L1: Phase 240Vac

L2: Earth.

Like that the device will have the necessary power (through L1). Will the device work and let me monitor L1-N voltage, i.e. earth to neutral?

Sorry, I meant ' Will the device work and let me monitor L2-N voltage, i.e. earth to neutral?

Hm. Theoretically, right, it should show the voltage between N and GND for L2, but in practice we did not check.

Tell us about the result later, please.)

:) I was hoping you check for me, in case I blow it up :) :) Can you check? You might be able to market it as another feature :)

Ok, we will check tomorrow)

That would be great, smart-maic team! Looking forward to results! Thanks!

We have checked, everything is ok with the device:)

But voltage up to 50Vac can be measured with error + -10%, I think it will be difficult to measure 5Vac on the line (

That's great! Yes, understandably there will be higher absolute error margin, but it may well be enough for what I need. What great support you have! Many thanks again!

If you make several control measurements with a multimeter, you will know the approximate % inaccuracy.

Exactly ... that's the plan! Will let you know how it goes.