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Author Topic: Steppers No Work!  (Read 8722 times)

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Offline Katoh

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Steppers No Work!
« on: January 17, 2013, 10:08:41 PM »
Colleagues
Embarrassment plus for me :-[ this not the first machine Ive played around with, but I can not get the steppers to move or even twinkle.
I'm using G203v drives putting 48v into them and have got them current set at 5amps. I'm also using two Homman BOB one is just for inputs and the other is to drive the motors and the Digispeed DCO3. What is really getting up my goat is the digispeed is working, the other parallel port all the pins are working also, but the motor outputs on that first BOB are just not working.
I have tried Active high/low putting the jumpers on all different settings but nothing seems to work.
Motors are wired in bipolar parallel, and are 570oz/in. But should be neither here nor there, I don't even get a whisper out of them where they should be singing away in tune.
Any thoughts?
Here is a quick snap of the BOB's the top one is for inputs the bottom for motors.
Cheers
Katoh
Cheers
Katoh

Offline Katoh

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Re: Steppers No Work!
« Reply #1 on: January 18, 2013, 01:45:23 AM »
Just a quick update, still cannot find the fault. When I go to jog one of the axis's I notice the yellow light comes on the gecko as well as the green. Strange indeed but still no movement.
Katoh
Cheers
Katoh

Offline Hood

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Re: Steppers No Work!
« Reply #2 on: January 18, 2013, 03:20:28 AM »
Attach your xml and I will see if I can find anything wrong with it.
Hood
Re: Steppers No Work!
« Reply #3 on: January 18, 2013, 04:02:32 AM »
H Katohi,

Looking at  the image the MB-02V6 at the top right is set up as;

Outputs 2-9"                    Pullups 5V
Outputs 1,14,16,17:         Pullups 5V
Inputs 10,11,12,13,15:     Pullups 5V

Common terminal voltage: 0V              <---------
Enable source:                 Enable Chip
D2-D9 direction:               Inputs



Looking at  the image the MB-02V6 at the bottom is set up as;

Outputs 2-9"                    Pullups 5V <----------
Outputs 1,14,16,17:         Pullups 5V
Inputs 10,11,12,13,15:     Pullups 0V

Common terminal voltage: 5V
Enable source:                 Enable Chip
D2-D9 direction:               Output



So, I'm assuming that the bottom bob is driving the G203Vs? If so the common is set to 5V. This is incorrect, you need to set it to 0V as the G203Vs use positive logic. Also the outputs pullups need to be 0V as well for the same reason.


Cheers,

Peter


----------------------------------------------------
Homann Designs
http://www.homanndesigns.com
email: peter at homanndesigns.com

Offline Katoh

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Re: Steppers No Work!
« Reply #4 on: January 18, 2013, 04:21:17 AM »
Thanks So much Hood, You have helped me out more than I can count.
I tried a few other things changing the cables still nothing.here is my xml.

Hi Peter
Glad you have chimed in also. You are correct the top board is the inputs only and works well, the bottom board only controls the DC03 and the Geckos, I have tried the jumpers in all different configurations but still can not get movement. I am leaning toward a gecko problem maybe.
Where should I have the jumpers set to on the bottom board? I followed your PDF diagrams on your website. But if you remember back I had a bit of trouble getting the DC03 to work, but we nutted that one out.
Many thanks
Katoh
Cheers
Katoh

Offline Hood

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Re: Steppers No Work!
« Reply #5 on: January 18, 2013, 04:45:35 AM »
First thing to say, if it is indeed a lathe then you can not use a Mill screenset as that will turn it into a mill :)
If you wish to use  the mill screenset you will need to copy the 1024.set to your desktop then rename to maybe theo.lset then place back in the Mach folder and from View menu in Mach choose Load Screens then in the drop down file type choose Turn and you should now see your renamed screenset.

Hood

Offline Hood

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Re: Steppers No Work!
« Reply #6 on: January 18, 2013, 04:48:12 AM »
Your steps per unit seem a bit low, could that be the problem, ie motors turning but that slow you hardly see?
Hood

Offline Katoh

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Re: Steppers No Work!
« Reply #7 on: January 18, 2013, 05:05:54 AM »
Actually Hood I was wondering about the screenshot also, and because I haven't seen a lathe in action I just assumed it was the same screenshot as the mill. Now I'm not too far into it to, maybe  just reload mach I have the latest version downloaded it last night and just start from there, The way I'm going there is not many things on there anyway.
The steps/mm I thought was correct. Both ball-screws are  5mm /turn X and Z and Z has a slight mechanical advantage being belt driven  at a ratio of 1 turn motor = 3/4 turn ball-screw.
Could it be this simple? Have I just miscalculated the whole thing. I'm not sure now.
Thanks Muchly Again
Katoh
Katoh
Cheers
Katoh

Offline Hood

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Re: Steppers No Work!
« Reply #8 on: January 18, 2013, 05:14:47 AM »
200steps per motor rev with 10 microsteps  2000 steps per motor rev multiplied by 1.3333 for your gearing = 2666.6666666 per 5mm so divide by 5 to get per unit (1mm) = 533.3333333 so more than 13 times more than you have set for X and 17times more than you have for Z.
Hood

Offline Hood

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Re: Steppers No Work!
« Reply #9 on: January 18, 2013, 05:17:41 AM »
Just noticed you ony have reduction on Z so Z will be 533.3333 and X 400

Hood