M41 SPINDLE MALFUNCTION 1

[valex]

Please help me

i work with a mazak vtc 20 b and when i try to start spindle it show me a alarm "M41 SPINDLE MALFUNCTION 1 "
the spindle drive show it "F4 32"

The machine opening normal and it going to home position normally the problem occurs when i try to start spindle

if anyone can help me i would appreciate it

 

[valex]

I found that when I open the machine, the axes go to the home point. So far everything is normal.
when I turn the spindle by hand on my screen it shows revolutions per 8 for example 8 then 16 then 24 then 32 then 41 then 49 and this continues as I increase the revolutions by hand .
Maybe this shows you where the problem is ?

 

[noname777]

Go on the top of your machine and remove the top cover of your spindle motor and inspect PLG sensor, if it is very dirty or mechanically damaged. Good idea to check the gap ( approx. 0.1 mm to develop 3 Vpp phases A and B voltages) and pre-amp output voltage with oscilloscope. If all looks good, no damage or lose wire, get power transistor unit inside your spindle amplifier replaced. All you can do at this moment or replace the whole MDS spindle amplifier