[guhl]

for spindle testing I would swap only PCBs.
you can see ladder on CRT
I think you should to invite service man

[Prnya]

for spindle testing I would swap only PCBs.
you can see ladder on CRT
I think you should to invite service man

Ok, I must find service man

[Prnya]

The sensor has been changed and the spindle motor now works fine, but there is another problem for me now. It still picks up the alarm 02 (Excessive speed deviation). It always occurs at the very beginning of the rotation of the spindle M3 or M4.There are no rules, it sometimes works 2 minutes, sometimes half an hour, sometimes an hour...But always throw out at the first turn of the M3 or M4, never while running in one direction and while I'm sticking with M5.
Does anyone know what could be a problem?

[tc429]

was about to say the noises sounded like a bad mag sensor in the motor...funny, they 'fail' from the permanent magnets dying...try sticking a screwdriver on a 'bad' one vs a new one- the bad one will have almost no magnet...
on the alarm, *maybe* just initially start at 100 rpm- if it does the same squeal/fwd-rev rocking, i'd close the new sensor gap down- maybe you got a old one and its weak too. also, look at the face of the old sensor- if rub marks, the tail bearing in the spindle motor probaby shot allowing wobble/rotor gap variation... if you decide to replace a tail bearing, do NOT be tempted to pull the reluctor wheel off the shaft...its dead soft iron, will pull right off... and be bent as if made of lead heat with a propane torch and a gloved hand will slide it right off... take care not to dent any of the teeth- and be sure to measure the installed height on the shaft- theres no shoulder on most motors.

if starting at 100 never rocks/squeals, it might at least start more reliably- if so, i'd change the drive current limiting to type 2 (i think- the one for acc/dec only anyways)