Anyone Using An Ajax Dm45nc Mill?

Ok - been working with this new beast and have written a couple programs that ran just fine in aluminum. I went to run a piece of copper and the spindle kept shutting down. No error message until the x or y axis would error out for full power with no movement. Hit the E stop, and raise the spindle and hit start and it would start up again. It got worse the longer I worked - eventually shutting down for no apparent reason (no load, just sitting there running) - still no errors. Nearly impossible to get to shut down when I have a meter in my hand, in true intermittent style! Running idle, the 2 hp motor is drawing 1.4 amps per phase and the three phases are running about 250 volts from phase to phase and about 175 from each phase to ground. The current readout matches what I measured with my clamp on meter (1.4 amps). I'm guessing the VFD is shutting down, but it must be a failure, since I can't see any external cause. The VFD is an automation Direct GS2-2PO 2 HP running on single phase input. Anyone know anything about these VFD's? I am starting to go through the manual now. It is rated for something like 7.5 amps. Is that the sum of all three legs or per leg? Not familiar how three phase is rated current wise. By the way, neither the motor or the VFD felt or smelled hot - just slightly warm to the touch, so I don't think it is excessive heat.
 
The guys on the CNCzone AJAX forum are the best bet. I know there are some diag dumps and settings to help but do not know them. Something smells amiss (obviously). I supposed just getting into the motor Xformer and checking connections and leads up to the serveo just to check and.or just issue a reconnect? Sorry I cannot help more but that system is very elaborate w/safeguards. Some you can mess w/ some you cannot. post to the AjaxCNC guys on the zone. or the free Ajax support forum (old php forum) but it opens a service ticket w/ Centroid. You'll see "countryguy" all over that board!!! . A great bunch!
 
I know if my hunyang does fault I get an error condition on a pair of Alarm contacts. 1 for alarm and 1 which is interlocked to the PLC to STOP the mill. So you could check for those VFD alarm contacts and see if they are wired up. They should be. As I just followed the print. The latest manual has a explicit setup for your VFD as it is 99% identical to mine and it's the setup I followed.

If there are no fault alarm connections, then check the OpCodes for the VFD and set it to runthe relay. (I think that was code driven?) maybe hook up a small alarm. I guess we can see if that goes off?

I guess I am saying that on mine- If the VFD faults, The alarm outputs are wired into the PLC as interlocks to halt the machine.
 
Set up the programming on the VFD to you can run it from the keypad to see if the problem is in the VFD or in the controls. I've never had a GS-2 fail, and I've used a lot of them. My guess is the problem is in the control wiring. If the stop switch is a NC push button, check the contact block.
 
I actually had not thought of setting the drive to manual mode, but I will do that. I did see the #2 relay wired into the harness, which would default to an inverter fault. I have no manual on this machine, so I'm using the CNC10 install manual from the Ajax website. It shows a typical spindle fault connection. I have ordered a replacement drive, but obviously I would need to record all settings if i change it out, so I guess that is my next step - check to see how P3.12 is set. It also looks like I may be able to read out the last 6 faults in P6-31 through P6.36. Does anyone know if these are retained on power down or not? This may give me a clue as to what is happening. I ordered a new drive, just in case.
 
I think the faults are saved on power down.
 
+1 on that. But I believe only until the next condition that may overwrite it. ahhh chasing bugs. The hunt is always a bunch of fun too. Learned my 3:1 inside and out that way. I found literally most every wire and junction blck w/ loose screws on the wires. poor connections. grounds not grounded properly, and just plain poor upkeep.
So if you run the VFD manually as-in just turn it on and move the spindle around w/o the PLC going. Observe to see if the VFD faults. I will lean towards it runs just fine. (....and now it's in printed form... will probably go the other way around. :- ) do you need me to send anything along from my DVD? I can send the part w/ the GS2 fault interlock. It runs to one of the PLC of the relays. All Relay and I/O outputs can be observed from the main screen of Centroid OS. I think it's the ALT-i key? Its listed in the main manual anyway. It is like the mach 3 diagnostics screen and will offer good insigt into what may have tripped on this condition. (as I thought about this issue last night) You'll find it!
 
I don't think I can contribute other than suggesting MariTool BT30 holders. The ER collet holders are about $100 each. Made in USA as well. I think they are cheaper because they are only balanced to 20k rpm.
 
The machine has had lousy upkeep. The bellows chip guard foe the Z axis is in tatters, so I tried to get a replacement. NLA, so I tried Grizzly - nothing available - tried PM, no luck. I found one at Tormach, but it is too wide. I think I can make it work. The backlash in the X axis was in the bearings and I adjusted it out. Just did the same for the Y axis tonight. The Z will be a lot tougher, if I need to adjust it. I programmed the drive to control speed using the pot on the drive and wired a switch in parallel with the control for forward rotation and when it drops out now, I can flip the switch and keep it running. I am losing the drive speed control voltage and the forward control signal when it drops out. I have info from Ajax on how to monitor the control inputs and outputs, but so far it is still running. As near as I can tell, a heavy cut with a lot of vibration triggers the fault. I need to use it and monitor the controls to see if I can find out the actual fault. Need to check out the CNC zone Ajax forum but just have not done it yet. I have been on the Ajax support forum with mixed results. Did manage to finish my copper project after rigging my bypass switch and moving on to some work with brass, which is machining much nicer! I'll be making some nice heavy cuts in a little while, so I'll find out if the problem comes back. I did prove that there were no faults stored in the drive, also. I also accidentally proved that a drive fault will shut things down (I won't go into the embarrassing details on that). As for holders, I ended up buying several from Bolton tool for about $30 each (I ended up with an ER25. another ER16 and 4 ER20 holders and a couple drill chucks (one with 3/4 straight shank, one with a 1/2" and one BT30 shank). I know they are cheap Chinese, but they will work for me for now - they are actually very nice looking, but I have not checked the run out. I picked up a few collets from Bolton and several off ebay.
 
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