DIY CNC Stutter - Intermittent Issue

Hello,

I am struggling with a stutter problem that seems to come and go. I posted in the electronics section assuming the issue is the power supply. Before I go and replace the PS I wanted to throw this past the DIY forum and see if anything else comes up.

The problem: The machine will randomly stop while cutting occasionally it will studder a bit prior to stopping. This has happed in the x and y axis.

Solution Identified from Electronics section post: Switching power supply going into foldback/protection mode due to quick current pull from steppers. Un-regulated power supply is better suited to the stepper motor application.


Details on the machine:
- Frame is 8020 constructions with aluminum tooling plate uprights
- Rough travel: 48" x 24" x 7"
- Nema 23 motors (425 oz-in holding torque, 3 A rated current, 6.5 mh inductance)
- DM-556D stepper drivers
- Dual motor Y axis
- 5 mm pitch ballscrews (not ideal but was readily available when I built it)
- Limit switches, e-stops, & motor wire all runs in shielded twisted pair that is grounded to a common point in the control box (using mechanical limits and only use them for homing as there have been false triggers from vibration)
- Motor acceleration is set pretty slow at 6 in/s^2
- Typical cutting speed 60 - 100 ipm (Limited by my confidence in the machine to run without stalling somewhat limited by 5mm pitch ballscrews)
- Tooling: Carbide roughing 3 flute 3/8" or 1/2"
- Spindle: 2.2kw water cooled
- Controlled from Mach 3 through a UC100 into a C10 Breakoutboard

Initially there was only one switching power supply (non-branded 48V 12A) that fed the 4 motors. It was fine for a while but over time has started to show the stuttering issue more frequently.

Second power supply was added (Meanwell 48V 12A), this seemed to help but did not fully resolve the issue on heavier cuts.

The non-branded powersupply was replaced with another Meanwell of the same specs. Each of the power supplies are wired to a single point 120v connection. The same goes for each stepper driver.

With the two meanwell switching power supplies the machine is still showing the stuttering behavior somewhat randomly. I started up the machine today to run some plywood and two times in a row had the machine stall on me while jogging between the holes it was cutting at a constant speed. This stall was a few minutes after I started the machine up.

Below is a link to a video that show the machine stalling while cutting out a skateboard blank. This cut, using a 1/2" 3 flute carbide rougher, will pull 3.8-4A on the spindle readout. Based on the spindle I believe this to be about 50% load.

Theory on what is happening:

The stepper motors pulling enough additional current, in a fast manner, when the machine goes into a heavier cut causing the protection circuitry to think that there is a short circuit causing the power supply to foldback voltage or current or both causing the stall.

When there was only one power supply driving all 4 motors they would all stop once this stall occurred. Now that there are 2 power supplies (1 has both Y motors, the other has X and Z) X will keep going when the Y stall occurs.

Today I tried to prove what was happening by connecting the multimeter to the outputs of the Y axis power supply and watch the voltage. Naturally the machine did not show any issues while the multimeter was connected. I plan to continue to do this to see if I can catch something happening during a stall event.

I have done the math on the 5mm pitch ball screw at 50 RPM increments up to 200 ipm following the torque curve of the motor. I have a hard time believing the motor is stalling on the axis that has two motors vs one (There are heavy cuts in both directions the video just happened to capture Y which is the failure the is most frequently seen). At 100 ipm I think I should be able to stall the spindle prior to stalling the motors.

I have run the machine off of a different computer to prove that windows isnt doing something fishy in the background stealing resources from Mach.

Am I just running into the limits of a protected switching power supply?

https://photos.app.goo.gl/3d1hPXAWR7jp3ERT9

At some point I would like to update the X and Y ballscrews to 10mm pitch as once I can get this stutter problem resolved I will want to cut above 100 ipm. What is everyone opinion of the C7 Rolled screws from Automation for Less?

Thanks,

Have you been able to duplicate the stalling with the voltage meter attached?

Try combining one of your Y motors with the X, and one with your Z motor controllers.

Since you have both Y motors on the same power supply, when that axis is decelerating, both motors are inputting voltage feedback to the power supply. By splitting the two motors across both power supplies, the other controller and motor are acting as a load, helping to reduce the feedback on the power supply.

The last few paragraphs in this article describes this exact issue.

https://www.geckodrive.com/support/s...ly-basics.html

One additional thought... I believe that your power supplies have a +/- 10% adjustment via a small pot. Try dropping the voltage 5-10%. This may drop the voltage being fed back just enough to avoid the protection circuit from tripping in the power supply. This does affect the max speed of your steppers, but who cares how fast they can go if you are throwing away failed projects due to this issue. I have no evidence if this will work ornot, but is certainly worth an experiment to see if it has any effect.

I hope that this helps.

Thanks, John Z

Sent from my SM-G991U using Tapatalk

Quote:

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Originally Posted by JohnZ

Have you been able to duplicate the stalling with the voltage meter attached?

Try combining one of your Y motors with the X, and one with your Z motor controllers.

Since you have both Y motors on the same power supply, when that axis is decelerating, both motors are inputting voltage feedback to the power supply. By splitting the two motors across both power supplies, the other controller and motor are acting as a load, helping to reduce the feedback on the power supply.

The last few paragraphs in this article describes this exact issue.

https://www.geckodrive.com/support/s...ly-basics.html

One additional thought... I believe that your power supplies have a +/- 10% adjustment via a small pot. Try dropping the voltage 5-10%. This may drop the voltage being fed back just enough to avoid the protection circuit from tripping in the power supply. This does affect the max speed of your steppers, but who cares how fast they can go if you are throwing away failed projects due to this issue. I have no evidence if this will work ornot, but is certainly worth an experiment to see if it has any effect.

I hope that this helps.

Thanks, John Z

Sent from my SM-G991U using Tapatalk

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Thanks John,

I had two multimeters hooked up (one to each power supply) today. Interesting enough I saw the voltage vary significantly. On the Y power supply it ranged from 41V up to about 55V. On the X/Z power supply it ranged from 32V to 55V. I did not see any stuttering today, but I was not pushing the machine very hard as I was working on parts that I was not willing to mess up. The spindle load remained pretty low, max of 2.5A at a speed that idles at 2.1A.

Seeing this wide variation in voltage was enough to push me over the edge to purchase a linear unregulated PSU. It will be here on Thursday. I should have a good understanding if this solves the problem or not by the weekend.

The power supplies while idling are dead on 48 V. Lowering the voltage is an interesting idea but based on the range of voltage variation I was seeing.

Quote:

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Originally Posted by tfins

Thanks John,

I had two multimeters hooked up (one to each power supply) today. Interesting enough I saw the voltage vary significantly. On the Y power supply it ranged from 41V up to about 55V. On the X/Z power supply it ranged from 32V to 55V. I did not see any stuttering today, but I was not pushing the machine very hard as I was working on parts that I was not willing to mess up. The spindle load remained pretty low, max of 2.5A at a speed that idles at 2.1A.

Seeing this wide variation in voltage was enough to push me over the edge to purchase a linear unregulated PSU. It will be here on Thursday. I should have a good understanding if this solves the problem or not by the weekend.

The power supplies while idling are dead on 48 V. Lowering the voltage is an interesting idea but based on the range of voltage variation I was seeing.

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It seems the unregulated power supply is working significantly better than the switching supplies in this application. Ran the machine for a couple hours yesterday without issue. Thanks for the help

I am really glad that the unregulated PS is working good for you. Those Torroidal Power Supplies are awesome, and can absorb momentary surges of current, no sweat. You should never have the machine shut down due to the power supply going into fault mode as that mode just does not exist in your new PS. Now you should be able to push your motors up to their real capacity at your new PS voltage.

What power supply did you end up going with?

Thanks, John Z

Sent from my SM-G991U using Tapatalk

Quote:

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Originally Posted by JohnZ

I am really glad that the unregulated PS is working good for you. Those Torroidal Power Supplies are awesome, and can absorb momentary surges of current, no sweat. You should never have the machine shut down due to the power supply going into fault mode as that mode just does not exist in your new PS. Now you should be able to push your motors up to their real capacity at your new PS voltage.

What power supply did you end up going with?

Thanks, John Z

Sent from my SM-G991U using Tapatalk

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I ended up going with a toroidal from Automation Technologies. Added benefit is it comes with the 5V output so I could get rid of the 5V wall wart transformer that was powering the breakout board. I'm sure I could dial up the accelerations now that I know the power supply isn't going to give out on me.

https://www.automationtechnologiesin...4820-with-5vdc

Based on the torque curve for a similar motor it looks like I should be able to take the cutting speed up to 150 ipm before I see the force per ball screw drop below 100 lbs. Unfortunately based on my supported/supported ball screw configuration I really can't take the Y faster than 130 ipm before I could see whip in the worst case position. I think 10 mm pitch screws with the proper fixed/supported mounting I should be able to get to 300 ipm speeds. That will likely be the next item to update on the machine.

Quote:

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Originally Posted by tfins

Below is a link to a video that show the machine stalling while cutting out a skateboard blank. This cut, using a 1/2" 3 flute carbide rougher, will pull 3.8-4A on the spindle readout. Based on the spindle I believe this to be about 50% load.

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What spindle are you running and VFD Drive??

When you read the VFD Drive at 3.8A to 4Amps that is per phase times that by 3 so you are pulling 12Amps.

How is the wiring, spindle Grounding, spindle Shielded Cable and correct Shield Grounding??

Do you have EMI Power Filters, for the VFD Drive and the Power supplies??

Quote:

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Originally Posted by mactec54

What spindle are you running and VFD Drive??

When you read the VFD Drive at 3.8A to 4Amps that is per phase times that by 3 so you are pulling 12Amps.

How is the wiring, spindle Grounding, spindle Shielded Cable and correct Shield Grounding??

Do you have EMI Power Filters, for the VFD Drive and the Power supplies??

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I'm running a Huanyang VFD with and HY 2.2Kw motor. I assumed that the amperage read out on the drive would match with the max amp parameter setting. I believe I have that parameter underrated slightly at 9 amps.

The VFD is wired on a separate 220 circuit with a line reactor between the mains and VFD. VFD to the spindle is wired with the shielded spindle cable that is grounded at a single point to earth.

The power supplies do not have any EMI Power filters.

I have not ran the machine since the first time after installing the new unregulated PS. Likely I will need to run it again this weekend and will report back how it is running.

Quote:

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Originally Posted by tfinses

I'm running a Huanyang VFD with and HY 2.2Kw motor. I assumed that the amperage read out on the drive would match with the max amp parameter setting. I believe I have that parameter underrated slightly at 9 amps.

The VFD is wired on a separate 220 circuit with a line reactor between the mains and VFD. VFD to the spindle is wired with the shielded spindle cable that is grounded at a single point to earth.

The power supplies do not have any EMI Power filters.

I have not ran the machine since the first time after installing the new unregulated PS. Likely I will need to run it again this weekend and will report back how it is running.

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Your spindle Amp rating would be 8.5 to 9Amps would be correct, unless you have set the overload Parameters the VFD Drive will supply up to 200% more than your 9Amp setting, the VFD Drive reading of 4 Amps =12Amps so you have not set the overload to 100% or 110% seems to be safe for these spindles.

The spindle cable shield is incorrectly Grounded, you also have a Ground loop if you have 2 Main AC Power supplies connected to your machine, the line reactor will help a little, the EMI Power Filter is best, reactor is not needed. only a quality EMI Power Filter

The spindle cable needs to be corrected; the shield needs to be clamped to the Ground Plane and clamped at both ends.

For the Machines Main Power supply, would have to see some photos to help you correct it.

Quote:

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Originally Posted by mactec54

Your spindle Amp rating would be 8.5 to 9Amps would be correct, unless you have set the overload Parameters the VFD Drive will supply up to 200% more than your 9Amp setting, the VFD Drive reading of 4 Amps =12Amps so you have not set the overload to 100% or 110% seems to be safe for these spindles.

The spindle cable shield is incorrectly Grounded, you also have a Ground loop if you have 2 Main AC Power supplies connected to your machine, the line reactor will help a little, the EMI Power Filter is best, reactor is not needed. only a quality EMI Power Filter

The spindle cable needs to be corrected; the shield needs to be clamped to the Ground Plane and clamped at both ends.

For the Machines Main Power supply, would have to see some photos to help you correct it.

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I appreciate the help. I will check the overload parameter, but I can say that the spindle does not get much above ambient temperature while using it. The 4A reading is for 10 or so seconds so there probably isnt much time to overhead the spindle. Looking at the manual PD120 controls the stall prevention at constant speed. When it is set to 0 overload protection is off. I have not changed this parameter, so it is likely set to 0. I am not so sure how this protection helps as the machine is still going to keep pushing through the cut. The parameter description does not say that it triggers a fault only that it drops the frequency. I should add that due to the 5mm pitch ballscrews typically I am running the spindle around 15K rpm to get a decent chipload.

For the spindle shield I will get a clamp for the VFD end. From what I understand I need to do the same at the spindle end. Where would you recommend doing that on the spindle?

For the machine main power supply the machine now has one unregulated supply to provide power to the drives, stepper motors, and control board. I think you are saying that between the drive power supply and VFD supply there is technically a ground loop, correct?

To be clear on the amperage topic (and to get my head straight): 3 phase motors are rated for total current that can be used for the motor. The VFD rating is also the maximum current that the unit can simultaneously. Finally, the current shown on the display of a VFD is showing the current output for a single phase. The display showing only the output current of a single phase seems odd to me especially since you set the current rating of the motor as the total 3 phase current. I don't understand the fundamentals of how the VFD is measuring the output current but that may quickly answer the question if it is only measuring one phase output.

I have an Automation direct GS1 drive that is powering a 3 phase wood lathe. That one shows output amps and shows a load % (current readout vs motor current). This aligns to what I expected from the HY drive where if my motor current is 4A and the measured current is 2A the load is 50%. I will dig up the paper manual that came with the HY unit to see if it better clarifies the output current display. The PDF I have does not clarify it.

Quote:

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Originally Posted by tfins

To be clear on the amperage topic (and to get my head straight): 3 phase motors are rated for total current that can be used for the motor. The VFD rating is also the maximum current that the unit can simultaneously. Finally, the current shown on the display of a VFD is showing the current output for a single phase. The display showing only the output current of a single phase seems odd to me especially since you set the current rating of the motor as the total 3 phase current. I don't understand the fundamentals of how the VFD is measuring the output current but that may quickly answer the question if it is only measuring one phase output.

I have an Automation direct GS1 drive that is powering a 3 phase wood lathe. That one shows output amps and shows a load % (current readout vs motor current). This aligns to what I expected from the HY drive where if my motor current is 4A and the measured current is 2A the load is 50%. I will dig up the paper manual that came with the HY unit to see if it better clarifies the output current display. The PDF I have does not clarify it.

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The VFD Drive has nothing to do with the motor Amps, you set the name plate amps and that get you going, most that buy VFD Drives are just getting a package or buy the incorrect VFD Drive for the job, when using single phase to power, a VFD Drive the drive needs to be 1.732 x greater capacity than the motor current requirements.

They only measure (1) of the phases, this is the norm for most VFD Drives.

Your VFD Drive most likely has a max of 12 Amps output, and that is what it was giving you when the spindle motor was at 4 amps.

Your 50% is incorrect you are just playing with numbers, the max amps that shows on your HY normal running should be around the 3 Amps=9 Amps your motor nameplate Rated Amps, now they will go higher when ramping up to speed, or if you have programed a heavy cut that is more than the motor should be doing.

Drawing a higher current does not normally overheat these spindles. but can cause them to fail over time. the slower you run the motor the higher the current draw will be

PD119=120
PD120=110

If you post some photos, I will be able to see where you can clamp the spindle end shield, ideal it would be in the plug, but these plugs a not designed for shielded cable.

Quote:

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Originally Posted by mactec54

The VFD Drive has nothing to do with the motor Amps, you set the name plate amps and that get you going, most that buy VFD Drives are just getting a package or buy the incorrect VFD Drive for the job, when using single phase to power, a VFD Drive the drive needs to be 1.732 x greater capacity than the motor current requirements.

They only measure (1) of the phases, this is the norm for most VFD Drives.

Your VFD Drive most likely has a max of 12 Amps output, and that is what it was giving you when the spindle motor was at 4 amps.

Your 50% is incorrect you are just playing with numbers, the max amps that shows on your HY normal running should be around the 3 Amps=9 Amps your motor nameplate Rated Amps, now they will go higher when ramping up to speed, or if you have programed a heavy cut that is more than the motor should be doing.

Drawing a higher current does not normally overheat these spindles. but can cause them to fail over time. the slower you run the motor the higher the current draw will be

PD119=120
PD120=110

If you post some photos, I will be able to see where you can clamp the spindle end shield, ideal it would be in the plug, but these plugs a not designed for shielded cable.

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Here is the vfd side

Quote:

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Originally Posted by tfinses

Here is the vfd side

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Here is the control box

The issue seems to be back again. This time it appears that the Estop circuit may be what is triggering. Mach 3 does not show that it is the Estop right away through the uc100 monitor bit after a few seconds it does. After the studder today I was not able to move the x or y axis any distance prior to it stopping and saying the Estop was triggered. I restarted the computer and and CNC but the problem persistent. I restarted everything one more time and the problem appeared to go away until the very end of a cut where it studdered and triggered the Estop. Looking through the Estop wiring in the control box I am using unshielded wire from the control board to the box estop. I plan to tidy this up with some shielded wire.

This C10 breakout board and uc100 are about 7 years old now. Could something be going bad on one of those?

Quote:

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Originally Posted by tfinses

Here is the vfd side

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Are using a wooden mount is really bad, a Ground wire like that also can't be used, it will act like an antenna.

Like the snip I posted is how the shield needs to be done, so the VFD Drive needs to be mounted on a Metal Plate, this is Grounded with the Main Power supply Ground then the shield would be clamped to that, the shield also should not be exposed like in your photo, the tail you have attached to the shield would not be doing anything much

P-Clamp is the best for Grounding a Shield, to the Ground Plane (Metal Plate)

Your Main Power is Connected to R & S, and this should be R & T for this VFD Drive

So, the insolation needs to cover the cable as much as possible, and you only remove an area for the wires and Clamp

The wire snip is just an example, you should only trim the insolation where you are going to mount the shield Grounding clamp

Quote:

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Originally Posted by tfinses

Here is the control box

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So, you have a good Grounding Bus (Star Point) in your Cabinet, a little messy wiring though, the DC power wires should be Twisted in their pairs, no Grounds wires in the Twisting.

A question about your Main Power Supply, are you using (1) Main AC supply for your cabinet and the VFD Drive???

Need to see the Spindle end cable as well, there is not much you should have to do, and you should be good to go

Quote:

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Originally Posted by tfinses

The issue seems to be back again. This time it appears that the Estop circuit may be what is triggering. Mach 3 does not show that it is the Estop right away through the uc100 monitor bit after a few seconds it does. After the studder today I was not able to move the x or y axis any distance prior to it stopping and saying the Estop was triggered. I restarted the computer and and CNC but the problem persistent. I restarted everything one more time and the problem appeared to go away until the very end of a cut where it studdered and triggered the Estop. Looking through the Estop wiring in the control box I am using unshielded wire from the control board to the box estop. I plan to tidy this up with some shielded wire.

This C10 breakout board and uc100 are about 7 years old now. Could something be going bad on one of those?

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Shielded cable / wire is not normally needed for an Estop circuit, this most likely would not help this problem, the VFD cable and mounting would be the first fix to do.

Anything is possible, you have some quite serious wiring problems though, even though you have been running for a long time, all these little things add up, and over time they show up.

Quote:

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Originally Posted by mactec54

So, you have a good Grounding Bus (Star Point) in your Cabinet, a little messy wiring though, the DC power wires should be Twisted in their pairs, no Grounds wires in the Twisting.

A question about your Main Power Supply, are you using (1) Main AC supply for your cabinet and the VFD Drive???

Need to see the Spindle end cable as well, there is not much you should have to do, and you should be good to go

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The wiring could use a bit of tidying up. So you recommend all DC power lines to be in twisted pairs? This may be a stupid question but is that pre-made or are you suggesting to do it manually?

I have shielded wire on the Estop circuit now to be able to rule that out.

I have a good amount of heat shrinking on the spindle connection. I'll look back through my photos to see if I can find an image of when I did it originally. I am guessing you are interested in how the ground is handled through the connector?

The VFD is powered off of 220V circuit and is separate from the cabinet running off 120V. Therefore, the grounds for both are separate.

Quote:

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Originally Posted by tfins

The wiring could use a bit of tidying up. So you recommend all DC power lines to be in twisted pairs? This may be a stupid question but is that pre-made or are you suggesting to do it manually?

I have shielded wire on the Estop circuit now to be able to rule that out.

I have a good amount of heat shrinking on the spindle connection. I'll look back through my photos to see if I can find an image of when I did it originally. I am guessing you are interested in how the ground is handled through the connector?

The VFD is powered off of 220V circuit and is separate from the cabinet running off 120V. Therefore, the grounds for both are separate.

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Are that's another problem, when using (2) separate main AC power supplies like this, you will have a Ground loop, this is not a good idea to do this, as this too can cause the problems you are having also, which one is the worst, it hard to say as they are both quite bad, the Ground loop means you have no direct path to Earth /Ground so is not what you want.

The Estop shielded cable if it is grounded correctly then it will be ok, if it is not then it will create a problem

Twisted pairs, is very easy to do with two lengths of stranded wire cable, hold the two wires together in a vice or just clamp it to something, with it stretched out, put in your electric drill chuck and spin it until you have it twisted, then cut to whatever lengths you need

Quote:

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Originally Posted by mactec54

Are that's another problem, when using (2) separate main AC power supplies like this, you will have a Ground loop, this is not a good idea to do this, as this too can cause the problems you are having also, which one is the worst, it hard to say as they are both quite bad, the Ground loop means you have no direct path to Earth /Ground so is not what you want.

The Estop shielded cable if it is grounded correctly then it will be ok, if it is not then it will create a problem

Twisted pairs, is very easy to do with two lengths of stranded wire cable, hold the two wires together in a vice or just clamp it to something, with it stretched out, put in your electric drill chuck and spin it until you have it twisted, then cut to whatever lengths you need

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The ground issue will get fixed this weekend.

Twisted pairs sound easy enough. I plan to work on that this week.

For the shielded Estop wiring I am using two conductors with shielded foil and a shielded wire. That is connected to the star ground point and the control box end of the wiring only.

If we ignore the separate grounds for a second does having two main ac supplies that are separated by a few feet really a problem?

Quote:

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Originally Posted by tfins

The ground issue will get fixed this weekend.

Twisted pairs sound easy enough. I plan to work on that this week.

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Main Power supply, Grounding, then Shields, then Twisted pairs, twisted pairs is the easiest to do but won't fix the main problem.

Quote:

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Originally Posted by tfins

For the shielded Estop wiring I am using two conductors with shielded foil and a shielded wire. That is connected to the star ground point and the control box end of the wiring only.

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No Shield Drain wire should be used to connect to anything, and never connect a Shield to a Star Point Ground Bus, Shields can only be clamped to the Ground Plane wherever they end, as per the snips I posted. When a shield is connected like this, it's not doing anything other than being an antenna, that will cause interference with any electronics that are around.

Quote:

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Originally Posted by tfins

If we ignore the separate grounds for a second does having two main ac supplies that are separated by a few feet really a problem?

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Makes no difference how far apart they are, both services are attached to the same machine, there can only be ( 1 ) Main Ground, and Power supplied to a machine, you are not the first to do this and won't be the last. This is what a true Ground Loop is.

Your 240v supply should be a 4-wire supply, ( 2 ) hot, Neutral and Ground if you live in NA, this will power the VFD Drive 240v and split to 120v for the rest of the machine

The 240v supply would go to your cabinet disconnect, and then split from there to the VFD Drive. you would have a Breaker in the cabinet for the VFD Drive and ( 1 ) for the 120v side.

- Twisted pairs completed
- Single ground completed

I found something interesting with the UC100 connection. When the UC100 is connected into the C10 breakout board the outer metal casing on the UC100 makes everything on the outer connector go to dc ground. Since this connector goes through the aluminum box it connects the DC ground to Earth. This does not seem right to me. I isolated it using heat shrink/electrical tape.

Quote:

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No Shield Drain wire should be used to connect to anything, and never connect a Shield to a Star Point Ground Bus, Shields can only be clamped to the Ground Plane wherever they end, as per the snips I posted. When a shield is connected like this, it's not doing anything other than being an antenna, that will cause interference with any electronics that are around.

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So does the ground plane go back to the ground bus anywhere or is the ground plane just connected to the box which gets back to the star point grounding through the box?

The machine ran today for about 25 minutes without issue. Suddenly while it was traveling between holes on a drilling operation it studdered in the same way it has been. One difference this time is a UC100 error popped up. This happened two times in a row. In the manual the error is caused by the computer and UC100 loosing sync with each other. The computer has about 2X the requirements of mach 3. It is not connected to the network and is only running mach.

I am starting to think that this UC100 is on its way out and is causing some of the problems. It looks like most people are now opting for ethernet based motion controllers rather than USB. Rather than replace the UC100 I am thinking that one of their AXBB-E Ethernet Motion Controller/breakout board combos may be better than investing in something that looks like it is on its way out.

Re-reading this and other threads with similar noise issues I see a common recommendation of adding an EMI power filter. Do you have a particular brand or source you recommend?

Quote:

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Originally Posted by tfins

- Twisted pairs completed
- Single ground completed

I found something interesting with the UC100 connection. When the UC100 is connected into the C10 breakout board the outer metal casing on the UC100 makes everything on the outer connector go to dc ground. Since this connector goes through the aluminum box it connects the DC ground to Earth. This does not seem right to me. I isolated it using heat shrink/electrical tape.



So does the ground plane go back to the ground bus anywhere or is the ground plane just connected to the box which gets back to the star point grounding through the box?

The machine ran today for about 25 minutes without issue. Suddenly while it was traveling between holes on a drilling operation it studdered in the same way it has been. One difference this time is a UC100 error popped up. This happened two times in a row. In the manual the error is caused by the computer and UC100 loosing sync with each other. The computer has about 2X the requirements of mach 3. It is not connected to the network and is only running mach.

I am starting to think that this UC100 is on its way out and is causing some of the problems. It looks like most people are now opting for ethernet based motion controllers rather than USB. Rather than replace the UC100 I am thinking that one of their AXBB-E Ethernet Motion Controller/breakout board combos may be better than investing in something that looks like it is on its way out.

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The Gound Bus is mounted on the Ground Plane, Star Point Ground is the Bus, you should only have one Grounding point, where all main Ground wires are mounted

I have used a UC100 since they first came out and it has never been a problem, the Case is normally Ground or Common for Dc

Quote:

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Originally Posted by tfins

Re-reading this and other threads with similar noise issues I see a common recommendation of adding an EMI power filter. Do you have a particular brand or source you recommend?

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EMI filter the only one I recommend is TDK Lambda RSEN-2030L this Part number

This too has to be mounted in the correct place and wired correctly with correct Grounding

Quote:

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Originally Posted by mactec54

EMI filter the only one I recommend is TDK Lambda RSEN-2030L this Part number

This too has to be mounted in the correct place and wired correctly with correct Grounding

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Excellent, thank you. I am going to go after all of the other items and throw the EMI filter as a last effort.

I have the clips for proper shielding grounding. Getting those installed this week. Ran the machine yesterday without issues using a much shorter USB cable (3'). The previous cable was about 10' due to the location of the PC running the machine.

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Originally Posted by tfins

Excellent, thank you. I am going to go after all of the other items and throw the EMI filter as a last effort.

I have the clips for proper shielding grounding. Getting those installed this week. Ran the machine yesterday without issues using a much shorter USB cable (3'). The previous cable was about 10' due to the location of the PC running the machine.

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Yes, the USB cable if unshielded can be a problem if too long, shorter the better.

This type shielded and with ferrite cores is good for helping