Here is the inside of my controller box. Plenty of issues to deal with.

NOTHING is earthed or shielded.

The VFD should bt even be in this box and the VFD output wires are draped right over the unshielded inputs of the controller.

Many if the power cables are undersized. Labelled as 1.5mm, but looking at them, I don't even think they are 0.75mm2.

Plan... rewire the whole thing. Shield and ground everything. Move VFD to seperate shielded enclosure...Click image for larger version. 

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