Philips, Grundig, Millplus Information Collaboration

[jaideepshinh]

Dear Dave
Swapped motors- no improvement
Interesting update. It appears the new ball screw is a bit too tight. We compared it with the X axis where we changed the ball screw about 4-5 months ago, and there is a world of a difference in the starting torque and running torque. While this is not enough to cause power reading to fluctuate, but this is definitely high enough to result in the overshoot as the axis torque is higher than required during deceleration.
We are putting back the old ball screw now, will keep you posted on the results.
Best regards
Jaideep

 

[jaideepshinh]

Dear Dave,

There is improvement in the settling time after installing the old ball screw.
Settling time parameters 3283:
New ball screw - 250 (below this Y+30 Settling time overflow alarm would come very often)
Original ball screw - 200 (below this Y+30 Settling time overflow alarm would come very often)
(original parameter for this was 150)

I am looking into what else could be the cause. There is in fact a very interesting article in the iTNC530 technical manual regarding settling time- photo attached. Would you happen to know if any software or commissioning aids are available for Millplus V400-410? TNCOPT is functional for V520 onwards. (I do not have a Millplus technical manual available with me, hence checking in other Heidenhain controls to understand the behaviour)

Notes for the image:

MP1521 Transient response during acceleration and deceleration
Input: 1 to 255 [ms]
0: Function inactive

MP1090.x 1 Maximum permissible jerk on the tool path

Best regards
Jaideep

 

[Nerv]

Can you check if there if that replacement coupling spider is rigid enough? This is something that was replaced that if it isn't the same durometer (There is likely more than one hardness available for that component, swap out the Y axis unit if it has one) it would definitely contribute to this problem. Did you check for backlash now that the old screw assembly is back in place? Backlash of each component; Ballnut, the screw relative to the machine, determine what still has any play and how much (if anything).

Double check that everything is tight as well, from the scale mounts to the read head, a little vibration over time might have caused something to no longer be within the tightness required to insure overall assembly stiffness for the original servo settings to work properly. I'm still confident this is mechanical and changing axis settings will not be fixing the core problem.

 

[Nerv]

Hi Jaideep,

What is the verdict? Anymore information from further testing?

 

[jaideepshinh]

Hi Nerv,

Sorry for the late reply. Verdict is as follows:
1. DMG supplied ball screw is defective. I tested the starting torque and its double of the rated (their internal inspection sheets somehow came along with the screw. Torque to rotate is 2.6 Nm, whereas as per their test report it is 1.12 Nm). In addition, the torque values are varying.
2. We compared this to the next screw we received a few days ago- the Z axis screw is super easy to rotate in comparison.
3. With a little more oil and grease flushing, the old screw is working well. Some areas on this screw are having a small amount of bounce but for most of the area it is working fine. Also, component accuracy has become more or less OK after installing the old screw.

As of now I am in discussions with DMG for the replacement of the two screws (Incidentally, the Z axis screw received was rusted in some areas which is unacceptable for a brand new part. Our old screws don't have any rust on them. We have had a severe rusting issue with one screw in the past from DMG because of which I am not allowing even a slightly rusted screw from them in our factory).

Sorry for the late reply- I was visiting DMG for their open house at Pfronten. Incidentally they too are still using Millplus on some of their mother machines! It was very nice to see.

Will keep you posted on any further developments as they come up.

Best regards

Jaideep

 

[jaideepshinh]

On a different note, Has anyone successfully replaced the Rapid feedrate override switch on the millplus control? It appears to be a 16 position switch, with a 10 wire ribbon cable soldered to the PCB (photo attached)
My switch is dead in a few positions. I ordered a replacement operator panel on ebay USA- the switch on this too came in broken.

 

[vetalkp]

Good day to all. We have a DMU50 machine and I can’t configure the network. The motherboard has a 10BaseT port, anyone who has encountered this, please help.

 

[Nerv]

What control is on your DMU? If you can go into your "Software" screen to show your version of software we can start there. Even though the control has a ethernet port doesn't mean you will be able to use it for file transfer, it depends on the software version and if that option was unlocked on that version. Newer than V410 versions no longer need a coded option password to use the TCP/IP file transfer capability.

 

[vetalkp]

What control is on your DMU? If you can go into your "Software" screen to show your version of software we can start there. Even though the control has a ethernet port doesn't mean you will be able to use it for file transfer, it depends on the software version and if that option was unlocked on that version. Newer than V410 versions no longer need a coded option password to use the TCP/IP file transfer capability.

Here is the boot screen, version 410

 

[Nerv]

Hmm, any reason your loading that up on a computer monitor? Did the machine control screen stop functioning? Anyway getting TCP/IP working on that is possible, now you have to get the right software. I recommend finding a copy of CDS Lite, it's amazing. Contact your local DMG/Heidenhain and see if they can provide it for you.

 

[vetalkp]

Hmm, any reason your loading that up on a computer monitor? Did the machine control screen stop functioning? Anyway getting TCP/IP working on that is possible, now you have to get the right software. I recommend finding a copy of CDS Lite, it's amazing. Contact your local DMG/Heidenhain and see if they can provide it for you.

the monitor is temporary, and you don’t have the software. We do not have a DMG/Heidenhain representative

 

[Alsipsp]

Hello Alex,
The first problem is the BIOS, which will be gone without battery power. Further on SRAM (Batt.backed) will be gone which hold the machine constants (MC), tools, parameters etc.
If there is no copy of the machine constants, there is a problem, as each DMU 50 is similar, but the MC`s are different. Software (SW) limits, tool change positions etc.
If the Mill Plus is SW level 400 or above, the last machine constants are stored on the Hard Drive in D: "powerup" or “Startup" directory or another directory. The extension will be .MC
If not, the machine constants from another DMU50 have to be used and adjusted to this machine.
The .mc in C: are default machine constants and can only be used, if the MC doesn’t start at all.
Hope this could be of help.
Regards,
PGH Team

Good afternoon Please help! The situation is this: DMU50 Evo. In the evening the machine worked, in the morning it said it would not load. Doesn't see the disk or operating system. We change the battery, start it up - everything is the same. Then we install a disk from a similar system (I don’t know which one, but also MillPlus), because we have a donor. Sistmea is loaded, but since it is from another machine, the machine does not work. Then, in order to eliminate the possibility of breaking the board on which the hard drive is installed, we swap the original hard drive and the one that was used as a donor. As a result (I don’t know how), the entire PC does not start in principle, although power is supplied to the power supply. We disassemble and put the original hard drive back on the old board and turn it on. And... our machine started up. But another problem arises that we cannot solve. The constants contained lines 115 and 120. 115 indicates that the machine has 5 axes. He's gone. And we have error O23. Error on lines 279, 280 and 313. If you change the value to 0, then it does not generate an error, but then the machine turns out to be 3-axis. What we haven't tried already. The original CM.CM was recorded via a laptop, changed manually, but we were unable to keep the constants 115 and 120. They just disappear

 

[OperMikr]

If someone has the hard drive images of millplus controller for DMU50 please send me on email to [email protected]

 

[jaideepshinh]

Hi fellow members,

Is there anyone here with a 12000 rpm, 10KW spindle, in their DMG machines? Photo attached for reference. If you, could you please share parameters 4400 and 2491? or a backup of your machine parameters for me to study?

I have come across an interesting observation. One of the more common DMG Mori spindles (the 12,000 RPM, 10 KW spindle, 87 NM Torque) is the same as their 18,000 RPM spindle (same 10 KW rating, 87 NM Torque). Mounting bolts, motor characteristics etc everything are the same. Its just that the maximum drive frequency is limited based on which spindle is connected.

There are mechanical differences though- 12000 RPM is grease lubricated, 18000 is oil mist lubricated. I would assume the bearing number changes (steel balls vs ceramic balls). The front and rear housings would have additional ports for the oil mist to work.

However, for those who have the 18,000 RPM spindle and are needing to change it, it should be feasible to get the more easily available 12000 RPM spindle and swap it out without any changes to the machine.

I would need the parameter backups of the machines with the 12K rpm spindles to confirm if my understanding is correct.

best regards

Jaideep

 

[jaideepshinh]

Dear Members,

Closure to my axis bouncing issue (machine is now working well)-
1. The new Ball screw was jammed - DMG has replaced it with a new one. The replacement screw is tight but smooth, and not cogging like the previous one.
2. My LS 486 scanner had an issue - even though PWM was showing everything OK, everything was not OK. One of the springs had fallen off, causing positioning instability.
3. It has come to my attention that Millplus V400 series does not have proper diagnosis for scale errors- when we cleaned and remounted the scale, we got a Y+30 settling time error alarm directly on startup as the scale reader gap was not exactly set. In other machines you would see an amplitude too small/ hardware fault etc.

The machine is now running well. As a preventive maintenance, I am replacing all the scale readers with new ones purchased from Heidenhain, which will be done in the course of a week or two.

Best regards
Jaideep

 

[vetalkp]

Good afternoon, forum members. My machine has error E60, rebooting doesn't help. Can you tell me where to look for the reason?

 

[Nerv]

This is caused by your drives not sending a ready signal. Was your machine running well prior to getting this alarm?

 

[jaideepshinh]

@vetalkp I would suggest checking
1. your door switch. It’s interlinked with the drive ready signal if I remember correctly.
2. the connections on your drive interface cards in case if they’re slightly loose.

 

[vetalkp]

This is caused by your drives not sending a ready signal. Was your machine running well prior to getting this alarm?

Good afternoon. The machine worked fine, but very rarely an error appeared. Rebooting helped. And now even rebooting doesn't help.

 

[Nerv]

The connectors in the drive interface cards have contacts that can weaken over time and no longer conduct properly, making sure these connections are good is important and these connectors are one of the largest weaknesses of the entire machine. The relay modules that relate to the door switch are sometimes responsible as well, if you have someone close the door and try to enable the drives while you watch the estop relays you can see a pattern that can help diagnose what component is causing the problem.