Router has died. Need Advise Please.

[Washout]

Eddy (and others),

The topic of earthing and prevent loops is something, which I have struggled mentally with since I built my machine and thought I had it sorted until your extensive post on page 5 of this thread. Also what I have done may be correct for my circumstances, so just to check:

Firstly my machine is all metal and I have good conductivity right from the cutter tip to the bed (including through the spindle and bearing etc.). Initially when I built the machine I did think I needed to earth the driver/stepper CY cables back to the star point in my control box only (and from that to mains earth) with a separate earth strap from machine to control box star point and also to have the spindle earthed through the spindle cable shield back to the VFD earth point (and again from there to mains earth).
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However I was getting a lot of spurious e-stops and when I disconnected the earth strap from the machine and essentially relied on the spindle to VFD earth they went away i.e. my machine is only earthed at one point in the VFD whilst all the stepper cables are only attached at the control box star point.
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In light of your post I'm questioning that again and would welcome an opinion especially as I also use a circuit making touch plate and cutter when setting tool height/z zero.

[EddyCurrent]

This also mentions plasma machine requirements, I'm not familiar with plasma machines.

CNCCookbook: Dealing with noise problems

[JAZZCNC]

However I was getting a lot of spurious e-stops and when I disconnected the earth strap from the machine and essentially relied on the spindle to VFD earth they went away i.e. my machine is only earthed at one point in the VFD whilst all the stepper cables are only attached at the control box star point.

This indicates you have some issue in some other area on the machine or in control box as doing this as just side tracked the problem not cured it.
Noise is a bear to find You could try taking a earth wire from the spindle body back to Earth on the VFD this will ensure the gantry is earthed at least and probably the rest of machine if bearings don't isolate the rest of frame but still not create earth loop as it's not connected to Star point in control box.

Have you measured frame with a meter to see if it's putting out voltage.?