Hi
I have a 1,5Kw M440 in my selfmade cnc and it causes crazy problems out of blue now. Basically the machine has been a while unusable because when ever I enable the spindle (by connecting after the startup the front panels pins 5 and 9 if I remember correctly) my controller (Raspberry Pi and Protoneer shield) go crazy. The Protoneer shield just keeps on booting several times a second. If I disconnect the spindle´s 3 cables, no problem.
Also, if the M440 is grounded as supposed, it blows a fuse (or differential, actually). I measured 39 volts between the ground cable and the chassis (here in Barcelona we have 220V sockets). I have pulled the unit apart twice, but failed to see the problem.
It is really weird, as this appeared after some month of stand still.
Yesterday I ordered a brandless VFD to replace this pretty unit, surely would have been clever to ask before.
Thanks
-PropellerHat