Is spindle going bad?

[jim_stadtlander]

Hi, I am having a bit of a problem with what seems to be spindle related, at least that's what I am thinking. Perhaps others may know more.


When cutting a file, it seems as if the spindle cuts out and stops running. I have run this file many times over 6 years without this problem. Actually, this has never happened on any files. Now, everytime I run this file it is doing it. The VFD has the code OC on it after it happens. I have manually checked the wires going from the VFD to spindle and they appear ok. I have never had electric spikes coming in before.

I am suspecting that the spindle is wearing out and this is a sign of it?

This file I am running is one that works the spindle harder. I have slowed the cutting down compared to the past runs, and it still does it. I have tried running the file just cutting air, and no problems happen. Tells me it's the load? Could it still be electric spikes from the road but only shows up when actually cutting?

Has anyone else ever had this happen? Any thoughts or possible things to check will be appreciated.

Thank you, Jim

[ssflyer]

Hi Jim,

Never had it happen to me, but this is from some Yaskawa VFD literature, if that's what you're using:

Digital Operator Display Text: OC Over Current

Description:Overcurrent Drive output current exceeded the overcurrent detection level approximately 180% of Drive rated output current).

Causes: Shorted Drive output phase to phase, shorted motor, locked rotor, load too heavy, accel/decel time too short, contactor on the Drive output is opened and closed, a special motor or a motor with a FLA rating larger than Drive rated output current

Corrective Actions:Remove the motor and run the Drive without the motor - - - Check the motor for a phase-to phase short - - - Check the Drive for a phase-to phase short at the output - - - Verify C1-01 and C1-02 are set correctly - - - Check load conditions.

[jim_stadtlander]

I have an older unit that is equipped with a 3HP columbo spindle. Your description is about what is says in my manual.


Corrective Actions:

Remove the motor and run the Drive without the motor - - -I Have run cutting air without problem. But what do they mean "drive" without motor?

Check the motor for a phase-to phase short , Check the Drive for a phase-to phase short at the output - - - Not sure what this means.

Verify C1-01 and C1-02 are set correctly - - - I have checked these(mine are different code numbers) but all are set correctly for HP, frequency, etc.


Check load conditions--- I have been cutting this for six years and it has been fine till now. See below.


I had always assumed that when a spindle gets old, its the bearings that tell you. I am wondering if there is a short going on inside the motor while under load from old age?

[ron brown]

Three phase motors are extremely reliable. Seldom have I seen one short out. There are many explanations on how to check them according to GOOGLE.

When bearings wear out, noise is usually an early indication. 'Run-out' becomes apparent in the cut too.

Good luck,

Ron

[jim_stadtlander]

It's not 3 Phase.

[zeykr]

Drive is referring to the VFD (Variable Frequency Drive)