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cavitt avatar image
cavitt asked

Easysolar 24/3000/70-50 earthing issues

Hi,

I have an Easysolar 24/3000/70-50 running at 230V 50Hz. I appear to have an earthing issue. Firstly i am an electrician so don't hold back with technical answers please. When i measure the voltages, i get the following; P & N 234V, P & E 92V, N & E 142V.It doesn't make any difference if the ground relay is open or closed. Is this just a phantom voltage and i can put a hard bridge between N&E (AC in is from a generator, so not earthed independantly) or is there something more serious going on.

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klim8skeptic avatar image
klim8skeptic answered ·

(AC in is from a generator, so not earthed independantly)

The ac input relay will close when the genset is connected, then the neutral-pe bonding relay in the multiplus will open. You need a neutral-earth bond in your genset.

multuplus-a.jpg




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cavitt avatar image
cavitt answered ·

Hi,

Thanks for the answer. i agree that there should be a bond between N & E on the Genset side. However i have the problem while running off the PV panels regardless of the relay being open or closed....?

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klim8skeptic avatar image klim8skeptic ♦ commented ·

Without ac coming in, the ground relay should be closed. (Unless you have it programmed otherwise)

ground-relay-a.png

ground-relay-b.png


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jc2010 avatar image
jc2010 answered ·

@Cavitt
I noticed that your N & E reading of 142 V summed with your P & E reading of 92 V equals your P & N reading of 234 V. Would this mean that a live conductor is shorted to earth somewhere in your system and this short is behaving as voltage divider with the center point on E & N somewhere between P & N ?

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kevgermany avatar image kevgermany ♦♦ commented ·
@Cavitt

Good point above. Panels cables should only be connected to the MPPT(through isolators etc.). Panel frames should be grounded.

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