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09-25-2011, 10:22 AM #1
Milltronics Mill Start Up Problem
Guys, I bought a used Milltronics MB18. Yesterday I got electricity to it for the first time. When I throw the disconnect on the machine everything seems to come up good except the control does not come up, just a black screen. The VFD for the motor comes up with no errors, all of the cooling fans start up, everything looks and sounds like it comes up except for the control.
I know it is hard to trouble shoot over the computer with such little information but does anyone have any ideas about what I should be looking for?
09-25-2011, 11:24 AM #2
Try connecting an external monitor to see if the monitor on the machine is bad.
Will the axis drives come on when you press "reset"?
09-25-2011, 12:03 PM #3
Some CNC controls won't run off of the cheaper VFD's. Did you check voltage and phase to to right?
09-25-2011, 12:44 PM #4
Might help to state the model of the mill and version of the control. I'm in the same boat, just bought a '92 Milltronics Partner 4 with the Centurion V control. It had been sitting without power for at least three years, I put power to it and all the fans run, and I get some info on the CRT about the EGA (video) driver (so I know the monitor works), but the computer itself doesn't boot and the servo drives are all dead until you get the computer up.
I have a friend helping me with the computer stuff (a bit over my head) and we have dead batteries on the motherboard and Simdisk card (board with all the machine software burned onto eproms). In the process of replacing batteries, upgrading to a newer 486 motherboard (was a 286) and a few other things.
You could have the simdisk card, or a hard drive depending upon vintage and revision of the control. Milltronics support has been excellent, but they don't have/know much about the controls before the Centurion V anymore. There are also upgrades available... depending on what you have as to how much though.
I'm just beginning to delve into all of this, I'm sure there are others much more knowledgeable....
09-25-2011, 01:06 PM #5
It is a 1998 MB18 with a Centurian 6 Control.
I am feeding the Mill with a 10hp Phoenix Rotary Phase Converter. It is a "CNC Grade" converter that is advertised as balanced within 2%.
In the cabinet is a VFD for the main motor (Yaskawa) for the spindle motor, this is controlled by the controller. This drive starts up without issue.
This machine was running when I bought it (at least it was in a video that was given when I was considering the purchase).
Nothing on the control panel will do anything. No lights for the buttons are anything. I can "mash" around on the panel and nothing happens.
I am thinking about looking over the wiring schematics and seeing if I can wire the control directly to 120v wall power. In case something is not quite agreeing with the phase converter.
I have heard that Milltronics is good to work with so I will most likely be calling them on Monday.
09-25-2011, 01:28 PM #6
If you are using a rpc make sure you feed the generated leg to L2 as the control runs off L1 and L3. I had lots of problems with mine at first because my voltage was to high. I had 248v, the service guy said max voltage is 232v. Any higher and you have lots of computer problems. Forget plugging the control into the wall outlet, it is not a simple thing to do.
09-25-2011, 01:34 PM #7
I am heading out to the shop soon. I will start with voltage checks and report those back. I work industrial mechanical maintenance in town and the electrical guys always talk about how the entire town is "hot" as for as voltage goes. They regularly talk about 490-500 volts on 480 service. If I am a little high on voltage how do I knock that down?
09-25-2011, 01:47 PM #8
Based on my experience with a Cent V controller, so take that as it may be..
I've been told that the 6 is similar, and the 7 has the control in the pendant/front panel box. Maybe I was told wrong?
You should be able to find the 110v power supply to the control. If it's anything like the Cent V, it'll be able to be plugged to a 110V extension cord.
CRT display? They are sensitive to being moved. You should be able to hook up a desktop monitor to the connector either right at the control box, or up in the pendant. Our Cent V at work has a 17 inch colour monitor, in place of it's 9 or so inch monochrome one, so it was well worth the effort to replace the monitor! But if the lights didn't at least flash while the machine was powered up...Maybe not that.
You got air on the machine? Gonna need it, though it shouldn't stop the control from starting up.
I'd start by looking at the connectors between the control in the back and the monitor/front panel. If they screws were not done up, the cables could have fallen apart during the move.
Pull the cover off the black box inside the control cabinet and start by pulling and re-seating all the cards in their slots. Check for disconnected connectors in there too.
I've run my Cent V control on a bench with a monitor and keyboard attached, just to see if it was functioning. It worked there.
Fuses? Plug pulled from the 110V power supply in the back?
I've dealt with Milltronics troubleshooting guys by email, mainly. They have been really good, helpful.
Have the serial number of the machine handy, as well as the serial number of the control box itself (should be located on black box).
Best of luck! I hope it's something really simple.
09-25-2011, 02:12 PM #9
The only thing 3 phase on that is the spindle motor. If your control is not coming up, check the fuses and the fuse on the power supply and the fuses on the line conditioners. Also, being the control is PC based (big black box inside the cabinet) take off the cover and make sure all of the cards and memory chips are seated.
09-25-2011, 02:53 PM #10
You guys are the best!!!
I checked all of the fuses and they were all good.
I pulled off the cover and there were two boards that didn't seem like they were seated correctly. Pulled them both and used some canned air to blow their connections out. Reseated them and applied power. Controller started up perfect. (at least so far)
Right now I have some more cleaning to do and put the Z-axis motor back on so I can get the machine to home. I had that off to get it in the shop.
The generated leg on the phase converter was real high when I checked voltages first thing. 260 to one of the single phase legs and 270 to the other. I unhooked one capacitor and that brought it down to 245 and 250. It measures 240 across the single phase legs. I am going to call the Phoenix tomorrow to talk to them about the voltages.
Thanks again guys, you are a BIG help.
09-26-2011, 08:11 AM #11
Well, after a long day yesterday it seems that I am back where I started. I got the machine up and went through the homing routine. The Z axis homed out fine, the X axis would then try to home next. If I would have it 8-10 inches away from the home position it would try to rapid over and about when it was a rapid speed it would fault out with a 449 "X axis servo fault". If I would leave the X real close to the home position (1/2") it would not home but go past home and go to the X travel overlimit and trip a different fault, 450 "E-stop".
So I began investigating two different problems, the home position switch not working and what looked like an acceleration issue causing the 449 fault.
I looked around in the controller for a while trying to find the X-axis acceleration parameter but could not find it, have to call Milltronics. Or do you guys have any other thoughts on this fault?
So after no luck with that I went to look at the homing postion problem. I traced the wires back to the panel and found the "Home" connecter to the PC in the cabinet. I pulled the connector and was going to probe it there, rather tough with my tester to check a pin connector, so I pulled off the PC cover to see if there was a good place to probe in there. There was not :-(
I went back around to the front and the control screen had funky lines and the numbers were showing up funny. I powered down and powered back up with the control now not coming up. I reseated everything in the PC again and still no luck.
At that point I was getting frustrated and it was getting late so I called it a night. I ended the day at the same point as the beginning, a control that would not start up.
I will have to regroup and come up with a new plan.
09-26-2011, 09:12 PM #12
Today after I got done with my real job I hurried home and called Milltronics to get some help with the problems described above.
We ent over the controller not coming up issue. After going over a few things he suggested trying a different moniter as you guys did. I do not have a monitor available so I took out the video card again and took apart all connections to reseat them. The controller them came up fine. I don't care for that but at least it is working for now.
Now to attack the homing issue. I was still getting the 449 X-axis fault when that axis was ramping up to full speed. The drive fault was an HS ECB fault. With the Milltronics Tech we turned down all of the acceleration parameters for that drive since that is what their troubleshooting chart suggested. That did not help the fault. It was close to their closing time so he asked that I swap axis drive cards and call him tomorrow. He suggested this to try to isolate the drive as the problem or the motor.
I swapped the cards with the Z-axis and still had the same fault on the same axis on the different card which is making look like we have a motor issue. The Milltronics Tech said that if it was the motor it was most likely a tach issue.
Now what??? Do I have any options like rebuild by a local motor shop or am I stuck sending it into Milltronics? Is there anything else that I should check before going this route?
Thanks again guys,
09-26-2011, 09:25 PM #13
What motors do you have on that thing???
09-26-2011, 09:49 PM #14
09-26-2011, 10:39 PM #15
I think I have the same motors, so, you can clean the tach. Remove the rear cover, should have 4 screws. Try not to tear the gasket, no biggie if you do, seal it with silicone if needed later.
You should see the encoder, take it off, the hole mount, should be 3 or 4 flat head screws. Move the bakelite dust cover, be careful with the wires if they are threaded through a hole. You should be able to see the tach brushes, they should move in the holders, I've seen them pretty gooked up and stuck. Use an electronic safe cleaner and hose it down, see if the armature is clean, scrub with scotchbrite if you can get in there.
You can take the motor apart but it's kind of a bee-otch, not impossible though. You have to remove encoder coupler then the tach plate but make sure it's marked with a witness mark to put it back together correctly. IIRC there is a snap ring on the shaft that holds the tach armature and the armature is a tight fit on the shaft plus it's keyed. Only do that as a last resort.
You can also remove the motor brushes by unscrewing the plastic covers and flushing with cleaner, don't over tighten the covers when putting them back on or they'll break.
If you have any doubts, don't do it, new motors are 2k plus
09-28-2011, 08:13 AM #16
I cleaned the tach and that seemed to help the 449 fault issue.
I now have the following issues, when I go to home the Z-axis homes properly. The x-axis and y-axis then start there homing procedure. They will both rapid and then I get an e-stop with nothing looking like it is on a limit switch. If I do this once or twice the e-stop will clear and I go go into the handwheel jog mode.
The y-axis and z-axis both seem to go up and down good. No matter what the x-axis is wanting to move on it's own. It constantly drifts one direction or the other. I can change the direction and speed that it drifts with the handlewheel on the controller.
The readout on the controller changes when I jog the y and z axis. For the x it does not.
Do I now have an encoder issue on that motor?
I still have a homing issue that is going to require me to take apart the x and y axis homing switches. The y-axis on is sticky and the x-axis although not sticky is not giving a homing signal to the control. The switch itself tests out fine.
I should note that when I cleaned the tach on the x-axis that I ran the table in and out so I could clean the commutator good. The encoder did not go back on in the same position that it came off, is that going to be an issue?
09-28-2011, 08:50 AM #17
Encoder's not going to matter if it didn't go on the same way but it could be failing if the motor is drifting and the readout is not changing.
I'm pretty sure I burned a motor up on mine last night. It err'd out and was so hot you couldn't touch it, then I could smell it, you know, that gross electrical smell.
09-28-2011, 06:13 PM #18
After much help from you guys and Milltronics it looks like I found my problem.
The 13 pin connector the hooks the X-axis up to the controller has 5 broken wires right at the connector. I don't even know how I got as far as I did. I kind of feel stupid for not finding it sooner.
My question now is how to repair this connection. There is no obvious way (at least to me) to take this connection apart. Will I need a whole new connector.
Any information that you can give me or point me to would sure be appreciated.
09-28-2011, 08:01 PM #19
Look in the bottom of the cabinet for a (black colored) pin pusher, it'll kinda resemble an apple corer on a smaller scale. That is the tool needed to remove the pins from the connector and originally they came with the machines. I can send ya mine if you promise to send it back. Need to know by friday morning. You can get new pins either from radio shack, digikey, newark, or possibly even from Milltronics, strip the wire and crimp them on or crimp and solder and push them back in. Cake walk!!!
BTW, my servo is toast and it took out the servo amp
that's a 2500 dollar bill,,,,,,,,,,, bummer but I may have an amp sooooooo it may not be that bad.
I found a blown fuse on the amp with the bad motor and replaced it, swapped to the y to check it, powered up the machine, enabled the axis's and BAM, sounded like a bomb went off, dam near blew the chips off it. My heart sank
10-03-2011, 09:49 PM #20
Well, this is the latest:
I fixed the broken wires on the connector according to the schematic that came with the machine. When I started up the machine everything came up nice. I reset the 450 e-stop fault and the x-axis took off and traveled about 6 inches on rapid and came up with a 407 fault. I reset it and the same thing happened. Only this time the x-axis ran out of travel, the thing shot right past the overtravel switch. This caused the four bolts that hold the ball screw nut into the housing to pull out.
I pulled it all down and drilled and tapped the holes out to the next size bigger Tonight I am back to where I was before. When I hit the reset button the x-axis rapids and throws a 407 fault.
Does anyone have an idea what a 407 fault is and what it might take to fix it?
I know that with the help of you guys and Milltronics I will get it fixed but this is sure getting frustrating :-(