Interact 4 Excessive Spindle noise

[iknownothing]

hi folks i have searched through the forums but could find nothing in relation to the issue i am having,
we have a few interacts here, ranging from 151 controls to 370's
they are each running pretty much 30-40 hours per week each.
We are now starting to see more and more problems, and as we have several of them we would like to try and maintain/fix as much as we can in-house.

The main issue at the moment is an interact 4 with a 370 control which was giving a spindle motor fan overload alarm, but then went on to give us a very nosiy main spindle. We always warm the spindles up each morning, around 400 rpm, but doing this now we see our main florescent lights in the workshop flickering badly as the spindle draws current. It is audibly louder than the other machines. We have only tried 1 production run since this happened , and at the end of cycle on an m25 the machine tripped out and the spindle coasted to a stop.

The machine has a sicme motori spindle,

Does anyone have any experience of this problem?

Thanks in advance.

[iknownothing]

Just been stripping some parts down to try and get to the bottom of this, and i disconnected the main spindle drive pulley and ran the motor on its own, from 200 rpm, 1000 rpm and then up to 2000 rpm. I then pressed the stop bottom and the spindle coasted to a stop and put the alarm "SPINDLE DRIVE FAULT" on the screen and the mentor 2 drive showed a fault code of AOC
anyone any ideas of what this fault means?

[gridley51]

AOC= armature overcurrent,probably caused by carbon dust build up in the comm area of the motor.I have that make of motor on a few machines and it`s prone to it.You should at least once a year check brush length,the condition of the comm and clean out the motor and you will get years without problems out of them.
I can`t remember if Control Techniques who make Mentors website`s address is .com or co.uk but a google will find it.You can download a manual from there but may have to register first.
Likewise Motori have a website which might have maintenance sheets on it,if not download something from SEM which will give you the basics of dc motor maintenance.Blower motors often get quite noisy due to the hours they are actually running,cheap and simple to fix with a pair of new bearings.Fit quality bearings rather than cheap no name types.
If you`re stuck with downloading the Mentor manual,I have it on disc somewhere.
Lucky you have Mentor drives,a motor flashover on an old style drive usually took the drive with it.The Mentors shut down before any damage is done to the drive.
Mark.

[iknownothing]

gridley51-thanks for the info.
I called sime motori uk twice in the past fortnight and both times they were very helpful and pomised me they would email me info on maintenance but unfortunately i have received nothing from them.

Are there any other sources for the info needed?

[machintek]

If you have the KTK spindle drive, it is also possible that one of the thyristor packs may be shorted. there are 6 of them at the very back of the drive. 3 for forward and 3 for reverse.
Fairly common to go. i am dealing with the same issue on a FANUC spindle drive.

George

[iknownothing]

HI- no its a mentor drive we have on this machine.

Just wondering how difficult a job it is to strip the sicme motori motor down and recondition it? Is it advisable to have a go yourself?

[gridley51]

If the Mentor is going out on OAC,you have an overcurrent fault.First thing is to disconnect the motor electrically from the drive andcheck the resistance of the field and armature,assuming it`s a wound field motor,then megger the armature and field windings to each other and earth.Check the brush lengths and make sure they are free to move in the holders.They are not difficult motors to strip,just take time and mark everything.
There could still be a thyristor problem in the drive as George suggests but I think that is monitored and would have it`s own alarm,although I would need to look at the manual to confirm this.
Another thought,has anyone one been altering drive parameters?It may be worthwhile checking the setting of,armature volts and max current,field volts and current setting,max rpm then do an autotune.
All this is assuming you have disconnected the motor mechanically and spun it by hand to check for binding and noise,likewise the machine side.
Motori have downloads on their site for which you have to register.I have registered but no reply as yet.
Mark.

[grigsby]

I have a boss 6 control. I have the 70007/60007 display. Does anyone near Southern IN. have an LSI-11 board they want to part with?

I appreciate any help.
Wayne
grigsbyatwowway.com