z axis

[arthurvenet]

hi guys i just hooked up my z axis i seem to be having a slight broblem with it, its not auto
focus its manual, when i drive the table up it works, when i stop and drive it up again it goes the opposite direction, and the same happens when i drive the table down. it seems like it dose not know which direction to go. all the parameters have been set i am using
the blue dsp controller, can somone shed some light on this subject thanks arthur.

[twehr]

hi guys i just hooked up my z axis i seem to be having a slight broblem with it, its not auto
focus its manual, when i drive the table up it works, when i stop and drive it up again it goes the opposite direction, and the same happens when i drive the table down. it seems like it dose not know which direction to go. all the parameters have been set i am using
the blue dsp controller, can somone shed some light on this subject thanks arthur.

Check your wiring. I had something similar where it would always go the path of the least resistance and "auto reverse" at the end. Turned out it was wiring (I think it was a bad connection, not a wrong one).

[baccus61]

Hi Arthur,
Check the signal wires on the DIR port of the DSP going to your drivers and see what voltage they are when you select up or down. The voltage need to be over 3.8 volts for it to go "High" or to change direction and under 2.8 volts to go "Low" but preferably 1.5 - 0 volts. It should be about 4.8 - 5.2 volts when High. If the voltage is switching around the 2.8 - 3.5 volts then it can go either way , up or down, because the voltage is just on the threshold of what it needs to "see" for a direction change.
Check the voltage on all the pins and see what they are when you change the direction and the speed. It should tell you something about what is going on.
Rich.

[twehr]

Here is a video of what was happening with mine.

http://www.youtube.com/watch?v=oJud0GDbUps

I went back and checked my posts and the problem went away when I rewired. I think there were a couple of strands of wire shorting out between motor phases.

[arthurvenet]

hi guys thanks for your quick respons i check out the wiring all seems ok, the signal cable seem to have 5.3 volts in any direction. i also notice that when i hookup the limit switch for the z axis and manualy hit the limit switch the z driver the 2M542 seems to go out on overload the limit leds is always on. i tryed a pullup resistor like the other axis which i had done prevuesly but it dose not work thanks arthur.