[Justintro8487]

I may have royally screwed something up! I over traveled the x axis in rapid mode before aligning the machine. I was ignorant to the alignment procedure. I tried holding the green power up button and hand jogging back down but kept getting the servo fallback alarm from what I am assuming is over voltage? I thought maybe something might be in a bind. Anyways the axis was up past the home switch so I loosened the servo motor from its bracket and spun the whole servo to bring the axis back down. The motor shaft does not spin freely because of the brake. I wanted to check to see if the brake was stuck so I pulled the brake assembly apart and all looked good. I put it back together reinstalled the motor and when I try to align the axis now I get alarm 44-45 which states is an axis follow error. When trying to hand jog the axis I get drive fallback alarm. I’m not sure how to check to see if the brake is getting voltage to disengage or not. I also am not sure if the machine has glass scales and the machine thinks it’s in the wrong position from me manually bringing the axis down. As far as I can tell it doesn’t have them. Im kind of at a loss lol! Any help would be greatly appreciated!

[servtech]

I may have royally screwed something up! I over traveled the x axis in rapid mode before aligning the machine. I was ignorant to the alignment procedure. I tried holding the green power up button and hand jogging back down but kept getting the servo fallback alarm from what I am assuming is over voltage? I thought maybe something might be in a bind. Anyways the axis was up past the home switch so I loosened the servo motor from its bracket and spun the whole servo to bring the axis back down. The motor shaft does not spin freely because of the brake. I wanted to check to see if the brake was stuck so I pulled the brake assembly apart and all looked good. I put it back together reinstalled the motor and when I try to align the axis now I get alarm 44-45 which states is an axis follow error. When trying to hand jog the axis I get drive fallback alarm. I’m not sure how to check to see if the brake is getting voltage to disengage or not. I also am not sure if the machine has glass scales and the machine thinks it’s in the wrong position from me manually bringing the axis down. As far as I can tell it doesn’t have them. Im kind of at a loss lol! Any help would be greatly appreciated!

When the drives are active and holding the axis in position, there should always be 24vdc to the brake. It's possible you mis-assembled the brake and it's sticking on, causing the following error (drag error).

[Justintro8487]

When the drives are active and holding the axis in position, there should always be 24vdc to the brake. It's possible you mis-assembled the brake and it's sticking on, causing the following error (drag error).

24vdc engages the brake?

[Justintro8487]

24vdc engages the brake?

Ok guys I decided to take the brake off the motor and see if I still had the same issue and lo and behold it aligned properly! Now I’m getting somewhere. Need to check and see if I’m getting voltage to the coil. Where does the dc power come from? Wanted to check and see if there is a fuse somewhere to check. The brake seems to be clean and free to move but maybe it has to be adjusted somehow? Thanks guys!

[maver1ck]

You need to get a set of electrical prints for your machine....there were differences based on vintage/drive package. The VMCs and I believe at least some of the TCs used a 90VDC brake not 24VDC. Regardless of the voltage, with no power the brake is engaged so the axis is held in position. With power the brake releases so the servo motor can move the axis.

There were also variations of the machines with no aecondart feedback, scales, or a 2ndary rotary encoder for position feedback. You really need to figure out which setup your machine uses to troubleshoot properly.

[Justintro8487]

You need to get a set of electrical prints for your machine....there were differences based on vintage/drive package. The VMCs and I believe at least some of the TCs used a 90VDC brake not 24VDC. Regardless of the voltage, with no power the brake is engaged so the axis is held in position. With power the brake releases so the servo motor can move the axis.

There were also variations of the machines with no aecondart feedback, scales, or a 2ndary rotary encoder for position feedback. You really need to figure out which setup your machine uses to troubleshoot properly.

I’ll look into them tomorrow. Would be nice to have the operation manual as well.

[meckardt55]

What control do you have? What color are the drives? How fast were you jogging the axis when it crashed? Can you hear the brake clicking when you start the machine the second time? You need to check if you have a scale on the X axis, on the right side of the X axis slide under a cover at the bottom. Do you get any error lights on the X drive? Were are you located?

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[Justintro8487]

What control do you have? What color are the drives? How fast were you jogging the axis when it crashed? Can you hear the brake clicking when you start the machine the second time? You need to check if you have a scale on the X axis, on the right side of the X axis slide under a cover at the bottom. Do you get any error lights on the X drive? Were are you located?

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Was jogging fairly slow. Control is acramatic 2100 with vickers drives. Check voltage to the brake on the motor and it’s not getting the voltage. Should be 90v dc. Does anybody know what supplies the voltage? I’ve check all fuses and they all ohm out good. I wiring schematic would certainly be helpful but just don’t have one with the machine at this time.

[maver1ck]

It should be 120VAC going through a rectifier to get the 90VDC. Probably will be on your output board but if you send me the electrical drawing # for your machine (found on the serial number plate), I'll see if I can find something similar enough to get you a better idea of what you will be looking for.

[Justintro8487]

It should be 120VAC going through a rectifier to get the 90VDC. Probably will be on your output board but if you send me the electrical drawing # for your machine (found on the serial number plate), I'll see if I can find something similar enough to get you a better idea of what you will be looking for.

I traced the 2 wires coming from the servo cable providing power to the coil back to the output board. Yellow and black wire. Looks like there is a 2 amp fuse and a board mounted rectifier next to each other neither of which are showing any voltage. The two wires I traced seem awfully small to be carrying 90vdc. I’m starting to think one of the traces on the output board may have shorted or possibly a bad I.O. Module. I’ll get the number off that plate in the morning. Really thought this was going to be an easy fix!

[Justintro8487]

The control diagram number on the serial plate is 9120 3107.

Also here is a photo of the actual output board on my machine.

[Justintro8487]

The control diagram number on the serial plate is 9120 3107.

Also here is a photo of the actual output board on my machine.

Little update on the machine. When I turn the spindle on I get no alarm but the spindle does not turn on. During the alignment procedure I get an alarm saying the c axis didn’t find its home pulse which is because it doesn’t attempt to turn. This is along with the issue of getting no voltage to x servo brake.

[maver1ck]

I actually read your 1st post in this thread now and somethi g doesn't make sense. You were jogging the X up, overtravelled and then the axis could not move down. I can not see any way the 110vac/90vdc brake circuit could have been damaged by you hitting an overtravel switch (24vdc). Is there any chance you shorted the brake circuit when you took the motor off?

I don't have any lathe prints with me right now but believe they used essentially the same circuit as on the VMCs so the rectifier will have both the input and ouput fused. After the output fuse the 90VDC will go through 2 relays (for "axis ready" and "brake off".

If you do find a bad track on one of the boards there is a chance I will have the board you need in stock, but won't be able to check until I get back to my shop.

[maver1ck]

Figured I'd attach the general circuit (but not from your machine so wire and relay numbers are likely not correct).

[maver1ck]

Trying the attachment again.

[Justintro8487]

Trying the attachment again.

I called Fives and they are emailing me the actual wiring schematics for the machine. Let you know what I find.

[gwood]

You definitely needed the prints from Fives to help anyone working on this machine. Wise investment!
I've attached a generic brake print that shows relays used on VMCs and you'll see
your diagram on sheet #7 of 91203107 is similar; but has minor differences.
Fives or a Tech can be of assistance if you need more help.
With the Drives started and NO-Faults have a qualified person check the DC Volts between P36 P1 to P36 P2 in the Cabinet.
Depending on what is seen; then proceed from there.

[Justintro8487]

You definitely needed the prints from Fives to help anyone working on this machine. Wise investment!
I've attached a generic brake print that shows relays used on VMCs and you'll see
your diagram on sheet #7 of 91203107 is similar; but has minor differences.
Fives or a Tech can be of assistance if you need more help.
With the Drives started and NO-Faults have a qualified person check the DC Volts between P36 P1 to P36 P2 in the Cabinet.
Depending on what is seen; then proceed from there.

Thanks for the help, yes the schematics are a must!
I figured I would share what I found to help anybody else in the future. I pulled the output board out and started checking traces and noticed that when I was originally trouble shooting the problem I had swapped relays on the board. As I looked closer at the board I saw that 2 of the relays are dc and one relay is ac. So I had the wrong relay on the ac side. That brought power back to my rectifier. Digging around a little more I noticed that the wires coming off pin36 going to the coil were broke. Repaired the wires and all is good with the brake again!

The last issue I seem to be having is when the align procedure tries to rotate the spindle to home it out for c nothing happens. The spindle doesn’t even try to move. No alarms on the drive. When I manually try to jog the spindle I hear a relay in the cabinet but still nothing happens. No alarm. Would this be a communication issue from the drive to the motor?

[maver1ck]

The only "communication" between the drive and motor is the power output from the drive to make the motor run (and I suppose the feedback from the motor to the drive/CNC).

Start with the basics and check that you have a connection to the spindle motor (remove mA, mB, and mC from the drive and ohm out the cables to the motor windings). There is a contactor to prevent the spindle from running if the door is not closed so need to make sure this is pulled in when checking (with power off you can manually actuate the contactor).

[Justintro8487]

The only "communication" between the drive and motor is the power output from the drive to make the motor run (and I suppose the feedback from the motor to the drive/CNC).

Start with the basics and check that you have a connection to the spindle motor (remove mA, mB, and mC from the drive and ohm out the cables to the motor windings). There is a contactor to prevent the spindle from running if the door is not closed so need to make sure this is pulled in when checking (with power off you can manually actuate the contactor).

Thanks I’ll check it out.