[BossMaint822]

Hello All,

Great forum, I have been a long time lurker, using many lessons found here to solve a lot of problems over the past few years.

I am slowly learning the ways of machine maintenance, and have encountered an error that is most frustrating and confusing. One of the machines I maintain is a Matsuura MC-1000V5 that is running on a Fanuc 11M system. A few months back it started having issues with the spindle "freezing" intermittently during a cycle. It happens randomly as to what the machine is doing, but gets worse the longer the machine is running. The freezing seems to be isolated to spindle spin commands (M3,M4,M5) and canned tapping cycles. No alarms are generated. The machine just stops moving through the program. Either the spindle won't spin up, or won't stop spinning in the direction it was from the previous command.

Another problem is I cannot access the PMC Ladder. We have 7 Matsuuras that run on Fanuc 11M and on none of them does the NC/PC button do anything. Is that a feature that has to be turned on? I had another technician look at it and he is concerned that maybe Matsuura didn't use the PMC at all and that maybe its just BMI all the way. It would be of great help if I could see where the machine is getting stuck for some direction in diagnosing this problem.

I have tried replacing a few of the relays that seem related to the spindle. I replaced: the top board on the spindle servo drive, the I/O connection boards, pretty much every board that has something to do with the operation of the spindle and even some that don't. No change. The only things I seemingly haven't changed are the entire spindle servo drive, and the spindle motor speed sensor/pulse generator.

As originally stated, I am slowly learning the intricacies of machine maintenance, especially anything that comes to the brains of the machine. I hope someone here can help me.

[oetkbyentc]

What is the spindle drive used (Fanuc, Yasnac)?
Does it indicate any alarms when the spindle has stopped while commanded to run?
Matsuura used to use a proprietary PLC for machine functions which could explain the lack of a ladder in the 11m. I don't know the MC- line so have you looked at that possibility?
If you simply run the spindle with no other operations active does this issue still occur?
Have you checked the run command and analog command to the spindle drive when the issue occurs?
If both are still present the issue could very well be the drive unit. be if a faulty drive or loose connection.

[BossMaint822]

The Spindle Drive is Fanuc, A06B-6044-H011. We have not looked at the possibility of a proprietary PLC, I will contact Methods and see if they can give us more information on that front.

I may have found the issue, apparently it took posting here for the gremlin to finally show its face. The last time it froze, the side control panel displayed number 34. This indicates that the orientation locking pin is not in position. I opened the head and the pin is fully unlocked, but the proximity switch was not reading. A quick test in the back showed it was not triggered, even when placing a piece of metal right against it, which triggered the LOCK position switch when I tested it. After spinning the spindle to confirm it was unlocked, I jumped the contacts and sure enough the machine carried to the next step. I replaced the proximity switch yesterday and ran a test program a number of times without issue. We are running parts in it today, hopefully the entire problem is resolved.

Thank you for your insight. I will update if parts of the problem persist.