353 OL Z axis error

[lostkoss]

Good morning,

Hopefully some of you fine folks out there have some advice for me.

I came in to work this morning and powered up my old Matsuura machine,(simple XYZ Mill)
everything seemed normal.When I got it to its zero point and turned the spindle on to warm up, 30 seconds later it just shut down by itself and the 353 Z OL error came up. Yasnac MX1 control.(Yeah, its old but in good shape and generally works well.)

My book says this error is caused by excessively heavy cuts, but the machine was just sitting at zero position warming up.

I followed the book advice and shut the machine down and let it sit for a half hour, I powered it up again and the z axis moved .0007 by itself and then error out and shut down, starting it up again several more times I was able to move all axis off of the limit switches but it continues to error out with the same 353 Z OL error.

Every time that error pops up the main hydraulics shut down leaving the control energized but no power to the machine.

Everything was working fine when I left on Friday.

Any advice?

[Al_The_Man]

If it is a Z axis on a mill, check to see if the counterbalance system is working, if it has one.
The other thing to do is if it is DC brushed, remove one of the armature leads, this is probably easier on the drive output, this will test two things, if the motor does in fact have an O/L or if the Z axis is drifting down, (counterbalance).
How did you move it off the LS, manually with the power off or by jog?
Al.

[lostkoss]

How did you move it off the LS, manually with the power off or by jog?
Al.

I was able to keep the machine energized for a few seconds before the error and jogged it off the limit switches.

Since then it errors out immediately.

[lostkoss]

Yeah Sorry,

I should have added that it is a simple XYZ Mill.

[Al_The_Man]

Even if it does not have a CB, I would do the Motor test. If it is an AC servo, you would need to disconnect the 3 stator wires.
Al.

[lostkoss]

Even if it does not have a CB, I would do the Motor test. If it is an AC servo, you would need to disconnect the 3 stator wires.
Al.

OK, thanks AL.

I'm not qualified to attempt that sort of fix.

I'm just the Programmer/Operator. I thought it might be something simple.
I'll let the company owner decide what to do about it, looks like we will have to get a tech in here.

Mondays !!!

[lostkoss]

This is a 1983 Matsuura MC-760V with a Yasnac MX-1 Control.

Looking over the machine and the message boards here for more information.

This old machine has two chains at the top connected to the Spindle Head.They slide over some pulleys and disappear behind the Spindle head into the back of the machine..

I presume these are part of a mechanical counter balance system. I can't see whats going on back there because the panel boxes completely cover the back of the machine.

We have had some problems with the Z axis on this machine in the past including random crashes and difficulty in holding Z dimensions from part to part.I haven't had a random crash in a long time though.

I'm starting to think my problems this morning may have been a long time in coming.

Could someone explain to me how these counterbalance systems work??
In Layman's terms please.

I just want some basic information BEFORE I call a Technician out , so that I have some idea of what I will be talking about.

Thanks

[LUCKY13]

I do not know how the couter balance system is setup on your machine, but basically it is a system that has weight at the end of the chains to help lift the heavy spindle head. WIth out this weight to counter the spindle weight the Z axis motor would have to work extra hard, with the weight it lightens the load of the job the Z motor has to do.


If something came loose or got off track with the counter weight system it could cause extra load on the motor and this may be how the system knows there is a problem, by reading/monitoring eletrical load on the motor. If it draws to many apps the system could know there was a problem. Ofcourse the motor could have a problem (electrical ) that could cause to many apps to be drawn.


I do NOT know anything about your machine but this sounds like what Al was getting at. If I am correct , then other things could cause the same problem, like a slide binding (which the spindle assy spides up and down on).



I think you are right about time to call a tech though. Someone could get hurt if they dont understand or know whats going on.


Jess

[lostkoss]

Thanks for the insight and the information folks.

I'll try to respond next week once we get the problem figured out.