First off: I love the thoughtfulness that went into the Ex controller and accessories. Nice work!
Finally got my EX controller retro-fit setup and somewhat cutting, but my Z axis is squeaking and losing steps.
This is my setup
KRMx02 with Ex controller
12 Inch Ballscrew Z axis with Nema 23
Tool height setter
Touch Plate for work area zeroing.
AV70S spindle.
I was making my first cut and started noticing the Z axis was making noise when trying to go up. I thought maybe my speed was too high for the Nema 23 so I reduced it from 200 to 100 in the wizard. That helped, but then noticed I was losing steps slowly over time. Again reduced the speed from 100 to 75, and once again still losing steps but not as bad.
Its squeaking like a squeaking wheel and sometimes knocks and the z will stop moving for a brief moment. It is brand new, but added a little bit of grease anyways. I think my brake is not disengaging or something? I was so excited because this retro-fit has taken me two months due to my machine is so old. I didn’t notice any problems while calibrating the tool height setter and touch plate, but the noise is getting worse.
And yes, my brake cable is hooked up. I am not even sure how the brake is suppose to work with CNC12, but I am assuming its working because my spindle never drops when I turn off the EX controller. I just have this feeling its still engaged while the motors are active.
I did read in the forums from someone else with a similar issue…
”Looks like you have a Nema 23 system. Those motors have lower torque than our other motors so they could be sensitive to a sticky Z axis… You may be losing steps during your cut because of it.”
You have to be kidding me lol. I know the Nema 23 has less torque, but didn’t think it would lose steps with the Pro ballscrew Z axis since avid offered it as an option. Would have been nice to know that before I purchased it. What?
Please tell me I can fix this. I noticed you all are back ordered on Z axis and I just cannot wait until the 18th.
The brake is engaged all the time when there is no power to the brake. It’s released when you move he Z axis the first time. If you don’t have it hooked up right, or configured right it will not disengage.
I would start by doing this: Unplug the power connector at the Z axis and probe it for 24 V after the machine is on, and you’ve moved the Z axis at least once. If you don’t see power there then the issue is in your wiring from that point back to the control box.
If you see power there then your issue is with the brake wiring in the Z axis or the brake itself.
Ok, if you’re seeing 24 volts after you move the Z axis for the first time that means that power is getting all the way up there to the brake.
The brake makes pretty distinct metal “tink” noise when it’s actuated. Are you hearing that when your Z axis moves the first time?
Something else you can try is to manually toggle the brake. Know before you do this that if you get the brake to release your Z could drop very quickly. So before attempting this put your Z somewhere on the table where you can get a block of wood under the drop plate. We don’t want it to drop too far, an inch or so is all you’ll need.
Once you do that from the main screen in Centroid press ALT-I. That will bring up the diagnostic menu:
Click on output 8 until it turns green. When it does that means the brake is actuated (released). You should hear that “tink” sound pretty clearly. If you have a servo machine the Z will fall very fast. If you have a stepper machine the stepper motor will be holding the motor in place so it won’t move, but we still want to hear that noise.
If you don’t hear the noise it’s best to open up a ticket with support which you can do with the contact button up top here. I’d encourage you to post a link to this thread, that way they can get started where we’ve left off here.
**BE SURE to return that PLC diagnostic menu to the same state you found it when you opened it up, this means click on that output 8 until there is no line above or below it.
ok so hitting OUTPUT 8 causes a “knock” and that knock appears to be coming from one of my steppers on the Y axis. Its completely reproducible 100%. There is no “tink” sound, just a knock similar to the sound you hear when you come out of E-STOP and the motors activate. I will fill out a support ticket. Thanks for all the help.
I apologize I led you slightly astray… All systems have a brake, but they work different on stepper and servo.
On servo the controller uses output 8 to command the brake on and off, on stepper the brake is energized when your steppers are energized, that way when the steppers are on they hold the axis in place and the brake releases at the same time. When you steppers lose power (controller goes off, you e stop) the brake loses power as well and locks the Z axis from falling.
Keep going with support so we don’t have communication lines crossed.
Hey Eric if you don’t mind I would like to check if I have power going through that cable The number one pin is power but I’m not sure what the other pin should be
Yes that’s what I was looking at sorry I’m not the sharpest tool in the shed when it comes to electronics I’m more of a plug and play guy but I do have similar issues like this thread just trying to eliminate some of the possibilities thank you!
m12 plugs follow a standard for power, ground and signal:
That’s the standard we follow. This will let you test at the connector, if you want to find and trace where those wires go you’ll need to find them in the schematics on that page. You can find the power adapter on those diagrams and you can trace the wire colors if you need to
Good news! Took off the brake and bench tested it. I just kept hitting it with 24 volts off and on like 30 times and it finally made a sound. I reinstalled it and my z axis is no longer squeaking. Still need to do some depth test cuts but I think its unstuck. I did see some metal shavings when I took it apart but everything seems tight and working now.
