THE BIG BANG!!! MAZAK AJV 25/405 FREQROL FR-SE 18.5Kw

ANyone please share your thoughts and advices with me.

I've been trying to bring back to life an old 1987 MAZAK JEWEL with MAZATROL CAM 2 and a giant FREQROL FR-SE 18.5KW after 30 plus years of pause.

The process of putting this machine to a stage where I was able to start and stop the spindle at 2000 rpm had been complex and tedious but nontheless it's been rewarding watching this machine recover its life.

However, last saturday while I was having fun watching things moving. at some point I decided to stop the spindle by pressing the RESET button instead of the usual "spindle stop" that I was using before and that caused a HUGE BANG sound inside the electrical cabinet and yeah! of course the spindle stopped!

I immediately went to check on what caused this big explosion to find out it came from inside the FREQROL spindle drive which btw it was all shut down. (no signals of life) Everything on the rest of the machine was still ON. After checking deeper into the FREQROL there were two IGBT bricks totally exploded badly!

Here are my questions. First of all, was it a big mistake to try to stop using the RESET button instead of STOP SPINDLE? since nothing happened before while I used the stop spindle button. Second question. I do have an identical FREQROL drive (from an identical machine) that I could use for replacement, but I am a little concerned that it might be necessary an adjustment for using each drive for each motor, even though both motors are identical and also both drives. but I think these drives are subject to a some sort of TUNING done at MAZAK factory with special tools that I do not have. I wonder how crucial would this tuning be?https://www.cnczone.com/forums/attac...d=473072&stc=1

Thank you for reading.

FLX

Wow... that is a toasty critter indeed!!! I am not sure what reset button you are talking about, but I'm guessing it did not do an orderly shutdown. Knowing how Mitsubishi has the servo drives setup, I'm guessing the spindle also shorts together the outputs. If that happened while the IGBTs were still running, it could certainly make a bang. But, this is all willy nilly logic because I have no real knowledge of the process you employed.

What I can tell is that the FR-SF drives have a set of parameters that are in the drive, but most of those are pretty basic. The more customized parameters are persisted in the NC and downloaded to the servo and spindle drives. I'm guessing the FR-SE follows a similar concept.

Quote:

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Originally Posted by MrMetric

Wow... that is a toasty critter indeed!!! I am not sure what reset button you are talking about, but I'm guessing it did not do an orderly shutdown. Knowing how Mitsubishi has the servo drives setup, I'm guessing the spindle also shorts together the outputs. If that happened while the IGBTs were still running, it could certainly make a bang. But, this is all willy nilly logic because I have no real knowledge of the process you employed.

What I can tell is that the FR-SF drives have a set of parameters that are in the drive, but most of those are pretty basic. The more customized parameters are persisted in the NC and downloaded to the servo and spindle drives. I'm guessing the FR-SE follows a similar concept.

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Thanks for your reply, I am attaching a picture showing the RESET button I was reffering to. Perhaps the fact that I had the spindle running on JOG mode, it did not like to be stopped from this other source. but I am just guessing.

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https://www.cnczone.com/forums/attac...d=473152&stc=1

Quote:

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Originally Posted by MrMetric

Wow... that is a toasty critter indeed!!! I am not sure what reset button you are talking about, but I'm guessing it did not do an orderly shutdown. Knowing how Mitsubishi has the servo drives setup, I'm guessing the spindle also shorts together the outputs. If that happened while the IGBTs were still running, it could certainly make a bang. But, this is all willy nilly logic because I have no real knowledge of the process you employed.

What I can tell is that the FR-SF drives have a set of parameters that are in the drive, but most of those are pretty basic. The more customized parameters are persisted in the NC and downloaded to the servo and spindle drives. I'm guessing the FR-SE follows a similar concept.

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Ah.... Thank you for the picture. Although I have a RESET switch, my machine interface is completely different from what you have. I'm almost guessing that you have a custom setup, whereas mine is a Mitsubishi part. It probably doesn't matter though. My guess is that, in the end, the machine designers are still interfacing to a Mitsubishi control element...

Anyhow, I had forgotten about my RESET button because I was thinking of some other mechanism (silly me). I would say that this is definitely not a normal usage of the button. By the same token, you should not be able break a machine with such a simple mistake. That is just BAD, BAD, BAD.... So, part of me is thinking that you may have had a weak IGBT, did something that wasn't really a great idea, that stressed the weak part, and boom! You may want to ask MEAU that though. One of the great things about them is that they support their products, at least to some degree, for a LONG time. Kudos to them! So, send them a summary of what you did and maybe we'll all learn something.

If your 2nd drive is from an identical machine with an identical motor you should be good to switch them. Just make sure to set all the settings the same on the top card. There will be some rotary switches if I remember correctly.

As for using the reset button, I used to do it all the time on my Leadwells with fr-se drives. hey were only 3.7k drives though. I would think the most likely answer is yours were ready to go, you just accelerated the process by telling them to essentially e-stop

Using the reset button as a way to stop the machine seems rather odd to me. However, I agree that it shouldn't cause the problem the OP noted. Either the IGBT's were on their way out or the drive somehow lost sequencing and shorted out two mains or something (that would definitely do it!)