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GREG021
16-05-2021, 02:13 PM
Hi All

I m hoping someone can point me in the right direction for a weird problem I have with my control.
Using UCCNC and separate drives for each axis.
If I try to jog say in Z, the Y and X move together. Some axis will only move in one direction sometimes not at all.
I have rechecked my wiring and all seems okay to me, I have also changed the BOB.
Please can someone point me in the right direction for tracing the problem?

dazp1976
16-05-2021, 09:41 PM
I'm prob barking up the wrong tree but...
I'd say it's your ports and pins settings myself.
What are your settings at?
For instance. If I'm using port 1 for a 3 axis starting from say output pin #2 I would assign.
Step = PUL , Dir = DIR. #x = pin no.

X axis= step #2, Dir #3. go to PUL-, DIR- on X driver.
Y axis= step #4, Dir #5 go to PUL-, DIR- on Y driver.
Z axis= step #6, Dir #7 go to PUL-, DIR- on Z driver.

I also always use enable too (generally from pin#14) wired to ENBL- on ALL drivers in parallel.
5V+ve power line wired to ALL drivers in parallel to PUL+, DIR+, ENBL+.

Assign pin#14 to output1, then assign enable1 as output1.

That's generally how I wire one of those generic 5axis boards that use parallel connection at least

A_Camera
16-05-2021, 09:55 PM
Hi All

I m hoping someone can point me in the right direction for a weird problem I have with my control.
Using UCCNC and separate drives for each axis.
If I try to jog say in Z, the Y and X move together. Some axis will only move in one direction sometimes not at all.
I have rechecked my wiring and all seems okay to me, I have also changed the BOB.
Please can someone point me in the right direction for tracing the problem?

You are not saying which UC controller you have, but my guess is that something is wrong with your configuration. Anyway, not enoug facts here.

GREG021
16-05-2021, 10:44 PM
Hi Daz

Thanks for getting back to me.
That is how I have connected it except the ENBL because STEPERONLINE support recommended it as follows.

Thank you using our products.
Our suggestions are as below:
1. Power Supply: 48VDC
2. SW1,SW2,SW3: off, off, on; SW4: off; SW5, SW6, SW7: on, off, on ,on
3. ENA+, ENA- : Keep no-connected
4. PUL+,PUL-: Pulse edge select Falling edge. as below fig,
dutycycly: 50%, frequency: 8KHz for a try( 300rpm)

Also, I have not assigned Pin #14.

What do you think?

GREG021
16-05-2021, 10:48 PM
Hi

Thanks for your reply.
I am using Stepperonline drivers with the cheap but Green BoB and setup with UCCNC.
The motors are the original Denford Easimill ones.
Does that help?

dazp1976
17-05-2021, 01:10 AM
Hi

Thanks for your reply.
I am using Stepperonline drivers with the cheap but Green BoB and setup with UCCNC.
The motors are the original Denford Easimill ones.
Does that help?

This one?
Pins 2,3,4,5,6,7 from right to left are axis.
PUL- , DIR- on drivers.
5V+ from psu direct to PUL+ & DIR+
(Enable doesn't have to be connected, it's a personal choice. Saves some power use at idle).
The 2 grounds in bottom corner can be connected together with a small loop.

Check this is all wired correct like this first.

https://warp9td.com/images/BOB_Vendors/NONAME/DB25-1205.png

https://upload.ecvv.com/upload/SMT/0000572/32819758138-kfhtb1dqcjsxxxxxcixpxxq6xxfxxxe.jpg

The other common bob is same as my 5 axis:
(single driver Y axis is shown).



https://i.ytimg.com/vi/rcUoUkdcE18/maxresdefault.jpg

A_Camera
17-05-2021, 07:02 AM
Hi

Thanks for your reply.
I am using Stepperonline drivers with the cheap but Green BoB and setup with UCCNC.
The motors are the original Denford Easimill ones.
Does that help?

No, it does not help. Stepperonline is NOT a CNC Drive product. I did not mean the stepper driver, but what you have between your stepper driver and the PC. Is it UC3005LPT, UC400, UC100 or what? Configuration is different for all those and the UCCNC license is locked to the product. It is the motion controller I was asking about, not the stepper driver. UCCNC must have a motion controller made by CNC Drive. Without that, you'll never get it working.

Doddy
17-05-2021, 08:01 AM
You don't (that I've read) explain if this a new set-up, or a set-up that did work and has now failed - that's kind of important to understand where you are. The question from A_Camera is relevant in terms of UCCNC controller - but that you're using a BoB suggests its not a AXBB, at least. Can you provide that detail as well?

Your fault description shows a common-mode failure across multiple axis. Yes, it could be a major cockup in the UCCNC configuration - but I'd be surprised. I'd look for a common-mode fault, such as a 5V supply failure (or wiring fault) to the BoB that's allowing it to limp under parasitic power but fails across multiple channels when there's an attempt to draw current - particularly as you describe an inconsistent behaviour.

For me, I'd isolate the controller from the BoB, and then toggle any single axis "step" pin on the DB25 connector between 5V and 0V (just a wire, nothing special) - for preference through a 1k resistor (just added safety) - if the problem remains at this level it's the BoB, or supply to the BoB.

EDIT: A photo of your control box could help.

GREG021
17-05-2021, 01:52 PM
Hi All

Thank you all for your help.
From your comments, I obviously need to give you more information.
This is a new setup. I bought the machine with a Gecko G540 but the connectors were corroded, so after hours of trying to sort it out decided to start afresh.
The cabinet contains:
3 off DM860I stepper drives.
1 ST-V2 Bob
1 UC100 motion controller
1 60 volt power supply
1 24 volt power supply
1 5 volt power supply
Control software is UCCNC

29974
29975
Please excuse untidy wiring just want to get it working first.
If it seems correct can someone talk me through fault finding? I do have a basic scope.

A_Camera
17-05-2021, 05:11 PM
I am sorry, I don't have time to talk you trough, but it would help if you'd answered ALL questions, when asked. We are only trying to help. For example, the question about if this never worked or it worked at one time, but now not working any more.

There is no need for an oscilloscope normally, a simple DVM would be more than enough to check all the wiring. The untidy wiring in itself is not disturbing me, but it is a good source of error. The picture you included is so small, it is for me impossible to see what is connected to where. Did you make a schematic of the connections, or you just started wiring? A drawing would be more helpful than a picture of the wiring in my opinion. Also, the second picture is showing ONE axis configuration, but you are not saying which one. Anyway, how about the other two axis configuration?

I also assume you bought an original UC100 from a legitimate seller, not one of those fake eBay copies. Those copies may or may not work, but most probably will never really get it right with a fake one.

JAZZCNC
17-05-2021, 05:31 PM
KISS is your friend when you have issues like this and don't have the experience to diagnose issues. So If you are not confident with the wiring then Go Back to Basics, remove the Rat's nest of wires from the BOB and just get one axis working, then rinse and repeat for each axis, checking as you go.

Then start adding other wiring like E-stop, limits, etc one at a time, again checking as you go. Don't bother with the enable as it's not really needed and just adds more complexity at this stage. You can always add it later along with monitoring the fault signals.

GREG021
17-05-2021, 05:35 PM
Hi Jazz

Thank you and sound advice will try that.

regards Greg

GREG021
17-05-2021, 07:26 PM
Hi
This is a new setup, the only original parts are the motors.
As explained the machine came with a Gecko G540 which had corroded connectors.
The UC100 is from UCCNC so is fine.
The axis config print is for the X-axis the only changes on the other axis is the pin and ports.
X-axis Pul- pin2 Dir- pin3 port 1
Y-axis Pul- pin4 Dir- pin5 port 1
Z-axis Pul- pin6 Dir- pin7 port 1

I hope that has answered all your questions. If you need anything else I am only too happy to oblige.

A_Camera
17-05-2021, 10:39 PM
Like Jazz said. Rip out all the wires and start all over again, one axis first. But before that, make a wiring diagram and start wiring when that is done and is right. Use the diagram as a guide and mark every wire you have connected. Use a multimeter to check the connection from point to point for every single wire BEFORE trying to run that axis. Don't power it up before that step.
Obviously something is wrong and you have no idea what, so I think also that it's best to start over. Just one more question. Do you use a 25 pin parallel port cable between the UC100 and the bob, or just a short ribbon cable? You could try a different cable just in case...

GREG021
17-05-2021, 10:45 PM
Hello

The UC100 plugs directly into the DB25 of the bob.
Great advice, I was becoming impatient after spending weeks on the Gecko.
I will do as you and Jazz suggest and be more methodical.

Many Thanks, Greg