Hello guys,
I have a question for skilled ones in electricity since I do not understand it. I had accident and would
like to know if it could be happen by switching spindle for ungrounded one.
I have two spindles 2,2kw water cooled. Old one and new one. Both are casual chinese versions.
I was not satisfied with sound of bearings of new one which I used for 1,5 year. So I
grabbed old setup I had aside and installed it. I used it for three days without problem, but
suddenly Motor on my Z stopped work. I measured power supply, it was ok. I tried cables from other motors,
still same. On support they told me to send it to RMA. So I did. I was thinking about if it is somehow related
with change of spindle. So I checked wiring, because it is old spindle from time when I started to build DIY machine
and understand to nothing. In that time I used it for 2 years without problem. What I found out, that spindle is not grounded and also on Huanyang VFD I had not connected grounding from spindle
to power cable and had switched grounding with negative. I add photo. So my question is:

1. Is it possible that motor could be damaged because spindle was not grounded, or
it should be just bad coincidence that happen in similar time ? (Spindle is connected just to VFD, not further like control board...)

2. Can someone please check the correction of VFD connection if it is right now how I marked ? (Ignore the yellow/green cable, it is really position 3 on spindle, I do not want to do resolder it) *

thank you