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Tenson
09-10-2012, 04:44 PM
I've got some CW5045 (http://www.cnc4you.co.uk/index.php?route=product/product&path=82&product_id=31) drivers and it seems like the dip switches are doing nothing like they are supposed to. Does anybody know the story here? I've tried it as if ON is OFF and vice versa, the results are still strange.

I've got 10mm ball screw and the motor has 1.8deg steps (200 steps per rev).

So if I wanted 1/5 microstepping I will need 100 steps per mm, right?

200 * 5 (the microstepping) = 1000 so that is 1000 steps per revolution.

1000 / 10 (the 10mm ballscrew) = 100 steps per mm.

Am I being stupid?

If I set the driver to what should be 1/5 microstepping it actually takes about 40 steps per mm. Huh?

Peter.
09-10-2012, 07:37 PM
Have you made changes in the software to reflect the steps per turn/unit?

irving2008
09-10-2012, 07:58 PM
Ummm...think I read somewhere here that the switches are upside down...or back to front... so Switch 1 is switch 8 or something...

Tenson
09-10-2012, 09:44 PM
I tired back to front and upside down.. it still doesn't do as expected.

I guess I just need to try lots of configurations until I find one that works right. What I thought should be 1/5th was actually 1/2 stepping.

What is the point of imperial and metric microstepping? Surely it doesn't really make any difference since the ballnut can position at any point on the ballscrew?

irving2008
09-10-2012, 10:59 PM
I think
'imperial' = 1/2, 1/4, 1/8, 1/16
'metric' = 1/5, 1/10, 1/20



Try a few different settings and put them in a table... it should then be obvious what the pattern is...

Jonathan
09-10-2012, 10:59 PM
Interestingly page 8 of this document says that the last 4 switches should be OFF,OFF,ON,ON to get 1/10, but the opposite is written on the driver (ON,ON,OFF,OFF). That would imply that you read '1' on the driver as meaning 'ON', so to get 1/5 try setting the last 4 switches to ON,OFF,OFF,OFF.


What is the point of imperial and metric microstepping? Surely it doesn't really make any difference since the ballnut can position at any point on the ballscrew?

Just to give you more options I suppose. If you're using the driver in some other system where software doesn't work out the number of steps for you it may be convenient to, for instance, have 1/5 as 1000 step/rev is an easy number to work with.

Tenson
10-10-2012, 04:16 PM
Thanks for the replies. I've tried a few settings and noted the results.

There seems to be no correlation with the table in the manual. However I just tried something that made all the results change; the Step Pulse and Dir Pulse setting. I did have them both on 5, then changed them both to 2 and the results were different as noted.

Any Advice?




SW1
SW2
SW3
SW4
SW5
SW6
SW7
SW8
Result


1
1
1
0
0
1
1
0
80 steps/mm 1/4 stepping (step Pulse 5 Dir Pulse 5)


1
1
1
0
0
1
1
0
1333.3 steps/mm (step Pulse 2 Dir Pulse 2)













1
1
1
0
1
0
0
1
200 steps/mm 1/10 stepping (step Pulse 5 Dir Pulse 5)













1
1
1
0
1
0
0
0
40 steps/mm 1/2 stepping (step Pulse 5 Dir Pulse 5)













1
1
1
0
1
1
0
1
500 steps/mm 1/25 stepping (step Pulse 5 Dir Pulse 5)













1
1
1
0
1
0
1
0
694.4 steps/mm (step Pulse 5 Dir Pulse 5)













1
1
1
0
0
1
0
1
583.5 steps/mm (step Pulse 5 Dir Pulse 5)


1
1
1
0
0
1
0
1
400 steps/mm (step Pulse 2 Dir Pulse 2)

Tenson
10-10-2012, 05:49 PM
I've got it all working as I want but the dip settings are all weird!

My long axis (Y) is driven by 2x CW8060 and they need the dip switches set as follows for 1/5th microstepping.



SW1
SW2
SW3
SW4
SW5
SW6
SW7
SW8


1
1
1
1
1
0
0
0



My X axis and Z are driven by CW5045 and they needs the following settings for 1/5th microstepping.


SW1
SW2
SW3
SW4
SW5
SW6
SW7
SW8


1
1
1
1
0
0
0
1



The manual of the CW8060 mentions a jumper for double or single pulse. I got these drivers second-hand so could that jumper be inside the unit and maybe changed by the previous user?