[alphatad]

I know the solinoid has something to do with it, but there's got to be more, otherwise, when i unplugged it, the alarms should cease...

[Mitsui Seiki]

I have found an alarm list.What 400 alarm is it?
And what control?

[alphatad]

sweet.
Alarm 400 servo overload
series 0-m fanuc.
i also get a " 1 " in the first column on line 720 in the diag screen

[Mitsui Seiki]

It just says "2nd axis overload".But you already know that.As far as I can tell from this alarm list a 1 at 720 just tells you that the overload signal is still on.
This didn't help you much,did it? Sorry.

[RavensMaster]

I have a Hardinge VMC 1000II with a 0-MD control that I bought new in June 2000 and it has been a nightmare from day one. It has had to be the worst machine tool I have ever owned. It took 27 months for them to get it to make parts without crashing. Also I have always had, or still have, intermittent 400 alarms … like 402 and 409. One pops up only occasionally and that’s the 402 (Overload) for the ‘Z’ axis. I don’t bother to call Hardinge to come service our machines anymore as they have to be some of the worst out there. I have, by accident, found that sometimes the 402 alarms have to do with the tac fan not working. Once the fan is replaced the errors go away. I found that to be the case with my 1000’s ‘Z’ axis yesterday. Finally I was unable to restart anymore … the alarm was constant. Diagnostic 722 is ‘1’ and the LED in the drive is ‘1’. I discovered that the fan was sputtering … and might have been bad all these years? Hardinge wanted me to buy the whole unit for $2,000. I found the fans online for $7.48. I reinstalled the assembly, with the new fan, but now the alarm won’t go away at all … even on boot up. The last 3 days I was able to restart and get going but eventually it would shut down again. Do you think the A06B-6079-H105 servo drive might be wasted finally from over heating? Could a stuck brake be the problem? Maybe the tac circuit is bad? We are going to trouble shoot the machine in more detail tonight but maybe someone has a few suggestions for things to look for or test for … thus saving us some time.

Thanks, Karl

[Mitsui Seiki]

It could be the servo.

[RavensMaster]

I found something else here that could possibly be an answer to my problem as it does describe the exact symptoms we're experiencing. I'm on my way out to pull the amp out again and check for these pots.

http://www.cnczone.com/forums/showth...ad+diagnostics

[Mitsui Seiki]

Yes, but these pots are set to specific value for a reason.If it gets to hot something is causing it.To set them to a higher value is not a good idea.Find the reason why things are getting hot instead..

[RavensMaster]

I have been busy playing catch up otherwise I would have posted this sooner. The drives in the machine are alpha drives so there are no pots on the boards. I found that the fan actually was the problem but that it’s a sensor fan, not a tach fan. I put in a proper fan and the problem has completely disappeared. It’s possible that many other users have had these problems and were told the amp was bad. If you get these alarms you should first see if the fan is running. If it’s in a tight spot to see into simply use a mirror and a flashlight to look down into the unit … of course you need to have the machine powered up. If it isn’t running then it will most likely be the first thing to try and fix or pay $2,000 – $6,000 for another amp … depending on which one it is. I usually buy 2 of each fan that is in the drives of each machine and convert them myself by using the pigtail from the fan that goes bad and reinstall it. I have saved untold thousands of dollars over the years. I hope this post saves someone else thousands of dollars.