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VMC unresponsive

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Aluminum
Joined
Oct 12, 2013
Location
San Francisco, CA
My company bought a VMC at auction, and it sat for several months before I was hired and tried to use it. It is a generic, brand-less Taiwan-made machine with a Mitsubishi Meldas 64s control.

I am typing this after our second visit from Mitsubishi and it still doesn't work. According to Mitsubishi, everything they can do has been done and the fault lies with the OEM. Since we don't know who that is, we can't go to them for repair. Can someone recommend a machine tool repairer who can come to Little Rock, AR, and who works on generic Taiwanese machines?
 
Let me rephrase this. I know who the manufacturer is, and it's Chuan-Yuan Automation Ltd., Co. I even have the manuals! However, I would personally consider this generic. This tag is the only identifier on the machine.

Anyway, I'm not really trying to identify the machine. I'm really just here to get a reference to a shop that works on machines like this.

IMG_3585.jpg
 
Do you have the documentation that came with the machine? Did the Mits tech talk about the "ladder" being gone?

I have all the documentation.

The first Mitsubishi tech fixed a lot of things that had gone wrong over time before I was hired on, such as the ladder, and he reinstalled the ALL1, ALL2 & ALL3 files. He was unable to diagnose why the shunt breaker tripped when the machine powered on, and he left with the machine still not operational.

The second Mitsubishi tech was able to get the axes to move and the spindle to turn by tricking the machine into ignoring error codes, but these changes would disappear when the machine is powered down and back up again. He noticed that the spindle oil chiller does not power on, which could be a clue.

We just wrote a large check for what we thought was going to be just homing the axes, but a two-hour job turned into a two-day job with no positive outcome. Mitsubishi has determined that the problem is with parts of the machine other than theirs, and not something they can fix or diagnose. That's why we need a third party repair shop to come to Little Rock. I'm looking for recommendations.
 
Start from the beginning. What happens afyer you turn it on. EXACTLY. Any alarms? What type of control and drives Etc. Let us try to help u nail down the problem.
 
Let me rephrase this. I know who the manufacturer is, and it's Chuan-Yuan Automation Ltd., Co. I even have the manuals! However, I would personally consider this generic. This tag is the only identifier on the machine.

Anyway, I'm not really trying to identify the machine. I'm really just here to get a reference to a shop that works on machines like this.

View attachment 223963

Ask them for a refund....
 
I have all the documentation.

The first Mitsubishi tech fixed a lot of things that had gone wrong over time before I was hired on, such as the ladder, and he reinstalled the ALL1, ALL2 & ALL3 files. He was unable to diagnose why the shunt breaker tripped when the machine powered on, and he left with the machine still not operational.

The second Mitsubishi tech was able to get the axes to move and the spindle to turn by tricking the machine into ignoring error codes, but these changes would disappear when the machine is powered down and back up again. He noticed that the spindle oil chiller does not power on, which could be a clue.

We just wrote a large check for what we thought was going to be just homing the axes, but a two-hour job turned into a two-day job with no positive outcome. Mitsubishi has determined that the problem is with parts of the machine other than theirs, and not something they can fix or diagnose. That's why we need a third party repair shop to come to Little Rock. I'm looking for recommendations.

Since you have all the documentation, it should not be too big a job for a good CNC tech to figure out the rest. I have no idea if there are any in your area. It's a bit too far for me to travel to....
 
How about laying out the electrical schematic on the table and start looking at brakers for the chiller if that's not working.
Some machines won't do anything before the chiller turns on.

If you have all the documentation then start poking around with a multimeter.

Marko
 
You need a good electrician. The problems with long time stopped machines are always electric. Batteries from axis are new? Batteries from control are new ones?
Electric schematic book and a good electrician is what you need.
 
It would be a good idea to get a local tech. Your prints are good, Mits control is no fun if you don't know your way around it.
Motor starter KM3 should be pulled in for the Spindle chiller to run. If it is pulled in, check the bottom of FR3 for 3 phase AC line voltage, if voltage is there the chiller should run. If voltage is there but the chiller is not running, the chiller has a problem. It usually has an circuit breaker or fusing in its electrical panel.
 
To add to ifixcnc's post...

If KM3 is not pulled in, look at relay CR0. If it is off, look at Diagnostic Y00. If it is 1 then CR0 should be on. If not on, check for a bad relay, bad wiring between I/O board and relay, or bad I/O board (no 24VDC on connector pin B20). If Y00 is 0 then you need to look at the ladder logic to see what conditions need to be met to turn on Y00.
 
Since you have all the documentation, it should not be too big a job for a good CNC tech to figure out the rest. I have no idea if there are any in your area. It's a bit too far for me to travel to....

Dude from Mitsubishi flew here from Atlanta. For real, do you feel you would be able to tackle this?
 
Some machines won't do anything before the chiller turns on.



Marko

If its a typical Habor chiller, open the top and tap on the relay that's at the very top. These become "sticky" and will prevent the machine from powering up. I've seen this on a few machines. Good luck with your repair.
 








 
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