[Fastest1]

Thanks Ray, I know that I have played with many different microstepping settiings only to find changes in speed but not accuracy necessarily. I get very confused on this topic and intentionally bring up what little I know hoping yours or someones correction will make it clear. I still wonder how the stepper could hold between poles with any predictablity. Of course there are many things I still wonder about this stuff. Like which class did I skip? Apparently all of the ones with this info LOL. Yesterday I saw you provide a formula on using a stepper for a power drawbar and the friction and involved. I am still trying to figure out how to word most of my questions. I always denied any reading or learning difficulties as a child, now at 50 maybe they were right. It is still fun though! Thanks.

[SCzEngrgGroup]

I still wonder how the stepper could hold between poles with any predictablity.

The rotor simply reacts, fairly predictably, to the forces generated by the current in the coils. When you run current through one coil, the rotor snaps to a position that puts it in alignment with the magnetic field in that coil. Do the same for the other winding, and it snaps into alignment with that coil. It does this because the magnetic field creates a force that pulls on the rotor, exactly the way two magnets attract each other. Energize both coils at once, with equal current, and the rotor will snap to a position mid-way between the two coils. This is exactly what happend in half-step mode. Increase the current in one coil, and/or reduce current in the other, and the rotor is pulled closer to the coil with the higher current. That is precisely what micro-stepping does. A single coil is energized at full current ONLY when the motor is at a full-step position. If you're doing 10X micro-stepping, the next step will reduce the current on the first coil by roughly 10%, and energize the other coil at roughly 10% of its max current, pulling the rotor roughly 10% off the full-step position. The next step will reduce the first coil current another 10%, and increase the second coil current another 10%, and so on. It doesn't work quite so simply in the real world, due to frictional and other losses and non-linearities, but that is the basic concept.

Regards,
Ray L.

[Mad Welder]

The rotor simply reacts, fairly predictably, to the forces generated by the current in the coils. When you run current through one coil, the rotor snaps to a position that puts it in alignment with the magnetic field in that coil......

As Ray says guy's have a look here it's a pretty good animation
How Stepper Motors Work

[Fastest1]

The rotor simply reacts, fairly predictably, to the forces generated by the current in the coils. When you run current through one coil, the rotor snaps to a position that puts it in alignment with the magnetic field in that coil. Do the same for the other winding, and it snaps into alignment with that coil. It does this because the magnetic field creates a force that pulls on the rotor, exactly the way two magnets attract each other. Energize both coils at once, with equal current, and the rotor will snap to a position mid-way between the two coils. This is exactly what happend in half-step mode. Increase the current in one coil, and/or reduce current in the other, and the rotor is pulled closer to the coil with the higher current. That is precisely what micro-stepping does. A single coil is energized at full current ONLY when the motor is at a full-step position. If you're doing 10X micro-stepping, the next step will reduce the current on the first coil by roughly 10%, and energize the other coil at roughly 10% of its max current, pulling the rotor roughly 10% off the full-step position. The next step will reduce the first coil current another 10%, and increase the second coil current another 10%, and so on. It doesn't work quite so simply in the real world, due to frictional and other losses and non-linearities, but that is the basic concept.

Regards,
Ray L.

Ray, Thanks for the explanation. I see MW has provided a link to a tutorial on steppers. I will have to watch it. I did believe I understood how the pole was attracted however I assumed all magnets were symetrically placed with 2 opposing magnets energized at the same time would create a central holding point. It never occurred to me about partially energizing one side and over energizing the opposite side. SD sorry to hijack your thread but loving the descriptions provided in helping my understanding.

[Fastest1]

As Ray says guy's have a look here it's a pretty good animation
How Stepper Motors Work

MW, great link and description, Thanks

[Mad Welder]

MW, great link and description, Thanks

Glad to be of some tiny help

[Fastest1]

MW, Unfortunately I learn in "tiny" bits. The timing was perfect! ;-)

[Mad Welder]

MW, Unfortunately I learn in "tiny" bits. The timing was perfect! ;-)

and you need a micrometer not a DTI to measure my "tiny" learning bits

[SwampDonkey]

Well, I got a new BOB, and new problems. This is the one I picked up:

http://www.tecnoflexo.com.br/site/fo...load/17/17.pdf

Now, in trying to wire it up I discovered that the little 4-screw terminal blocks were defaulted as 5V power supplies with the one the end being the ground until they were assigned Step and Dir pins in Mach 3. This doenst work, of course. With the machine configured in the way the manual illustrates the motor turns in one direction (sounds familiar). With an external USB cable providing my 5V it works fine. On the volt meter I get 5.08V from the BOB screw terminal and 5.18V from the UBS cable coming from my computer. Ive tried switching them around and nothing works.
Not only that, but when you assign a pin to step or dir, it stops being a 5V power supply...permanently. They now read zip on the volt-meter and I cant get the unassigned pins to go back to being 5V+.
The BOB is supposed to be supplied by USB, but it looks like I need a SECOND USB cable to power the 5V going to the drivers.

Any advice? This is white-knuckle frustrating. It seems like a miracle that people just buy their parts and build machines like this without the avalanche of problems im having. Where do you all learn how to do this? I consider myself to be pretty good at technical stuff but never before have seen anything like this- Example: The new BOB came with a manual that suggested a setup in mach 3 that didnt work. The wiring diagram I got with my drivers and steppers didnt work. How is this the way things are done? Its as if vendors expect you to just know what to do despite giving terrible advice.

[109jb]

Look at the attached picture.

Then in Mach you need to assign the following in the configuration menus (see pictures). Make note of the green check marks. This is how it should look for a 3 axis machine.

Under the "Motor Outputs" tab
X axis dir pin - 2
X axis Step pin - 14
Y axis dir pin - 16
Y axis Step pin - 3
Z axis dir pin - 7
Z axis Step pin - 8

Under the "Output Signals" tab
Enable 1 - pin 1
Enable 2 - pin 1
Enable 3 - pin 1

[SwampDonkey]

AH! Thank you 109jb:banana:

Its working...sort of.

I ordered a Keling KL5056 to replace my fried DQM5042MA driver. I wanted a Keling because everyone raves about them and I didnt want to worry about replacing another driver....So of course its broken.

Yep. The Keling is the driver that is malfunctioning apparently. I have it set up just like the others and it only turns one direction and VERY slowly. I have connected it to the other motors and different pin sets on the BOB and it has the same effect on any motor it is controlling. Damn.

I have it set up at 10 microsteps and 4.3A (to get close to the 4.2 of the other drivers). Setting it to half current when idle has no effect.I called up John at Automation Technology (who I bought it from) and he said to just send it back for a new one.

Is there anything I could be doing wrong? It just seems like the odds are against this happening.

[SwampDonkey]

Well, its not working any more. Or more accurately, it works in spurts or not at all. I returned my Keling 5056 for a new one (replacing the one that blew, which was itself a replacement for another that blew). So ive had to replace 2 of 3 drivers so far. Something is terribly wrong here and I cant figure out what it is.

Right now, only one axis will work. This is weird because when I was troubleshooting the bad driver, all 3 were working somewhat. None work all the time. If I turn off the machine and power it back on, random axis will work or not, or go in only one direction. The new keling driver doesnt move anything at all, fresh out of the box. I dont even know where to start.

And yes, Ive checked my wiring over and over

Any suggestions anyone?

[automationtechinc]

Well, its not working any more. Or more accurately, it works in spurts or not at all. I returned my Keling 5056 for a new one (replacing the one that blew, which was itself a replacement for another that blew). So ive had to replace 2 of 3 drivers so far. Something is terribly wrong here and I cant figure out what it is.

Right now, only one axis will work. This is weird because when I was troubleshooting the bad driver, all 3 were working somewhat. None work all the time. If I turn off the machine and power it back on, random axis will work or not, or go in only one direction. The new keling driver doesnt move anything at all, fresh out of the box. I dont even know where to start.

And yes, Ive checked my wiring over and over

Any suggestions anyone?

Do you have a green light on the driver?

We sold so many digital drivers, if one of them is not working, it is possible.
But it is impossible for all three bad drivers together. if you do not t know how to set up, pls contact us for support. we will help you

High-Torque Stepper Motor, Stepper Motor, Driver, Stepper Motor kit, DC Servo Motor, DC Servo Motor kit, Stepper Motor Power Supply, CNC Router, Spindle, and other Components. Automation Technology Inc

[SwampDonkey]

Do you have a green light on the driver?

We sold so many digital drivers, if one of them is not working, it is possible.
But it is impossible for all three bad drivers together. if you do not t know how to set up, pls contact us for support. we will help you

High-Torque Stepper Motor, Stepper Motor, Driver, Stepper Motor kit, DC Servo Motor, DC Servo Motor kit, Stepper Motor Power Supply, CNC Router, Spindle, and other Components. Automation Technology Inc

Yes, all three lights are on.

Im using the RJ-45 adapters from CNC4PC to simplify the wiring, and that may be the problem. Ive bought new 18g wiring to replace the $30 worth of adapters and cables I bought...

I was actually going to contact you in the morning. What number should I call?

Thank you much!

[SwampDonkey]

Do you have a green light on the driver?

We sold so many digital drivers, if one of them is not working, it is possible.
But it is impossible for all three bad drivers together. if you do not t know how to set up, pls contact us for support. we will help you

High-Torque Stepper Motor, Stepper Motor, Driver, Stepper Motor kit, DC Servo Motor, DC Servo Motor kit, Stepper Motor Power Supply, CNC Router, Spindle, and other Components. Automation Technology Inc

I emailed customer support, followed the directions in the return email, NOTHING.

Does anyone know how to wire this thing? I have the PUL- and DIR- set to the BOB output pins as per the wiring diagram, and the 5+ common to the rest. The ENA terminals are left unconnected. It still wont work!
Ive tried everything, and if its malfunctioning then this is the second Keling driver in a row from Automation Technologies to fail. The leadshine drivers from China are running like a champ.

Anyone have any advice?

[109jb]

are you running this on a laptop through a parallel port on the laptop by chance? If so, many laptop parallel ports don't output a strong enough signal.

[SwampDonkey]

are you running this on a laptop through a parallel port on the laptop by chance? If so, many laptop parallel ports don't output a strong enough signal.

Nope. A desktop. And it runs the other drivers perfectly. So I have 2 axis working and the one driving the Keling just sits there with the green light on.

[109jb]

I have the PUL- and DIR- set to the BOB output pins as per the wiring diagram, and the 5+ common to the rest.

I just re-read this part. What you have indicated sounds wrong for the BOB you said you have.

The PUL-, DIR-, and ENA- should all be hooked up to the GND terminal on the BOB. The PUL+ goes to the XS, YS, ZS.. as appropriate. The DIR+ goes to the XD, YD, ZD... as appropriate. The ENA+ goes to the XE, YE, ZE... as appropriate.

[SwampDonkey]

I just re-read this part. What you have indicated sounds wrong for the BOB you said you have.

The PUL-, DIR-, and ENA- should all be hooked up to the GND terminal on the BOB. The PUL+ goes to the XS, YS, ZS.. as appropriate. The DIR+ goes to the XD, YD, ZD... as appropriate. The ENA+ goes to the XE, YE, ZE... as appropriate.

Ah, nice. I'll give that a shot. This is the diagram sent to me from AT:

http://www.kelinginc.net/KL-5056WiringDB25.pdf

Along with the directions to leave ENA terminals unconnected.

Thanks! I will report back shortly

[109jb]

Both wiring options are valid depending on the BOB you use, but for the BOB you said you have it should be wired like this picture that is in the KL-5056D manual that you can download from the following link:

http://www.automationtechnologiesinc...load.php?id=51