Help with Stepper Motors

[Scott]

Hi guys this is my first post !!

heres my problem its not a big problem but still i would like to sort it out

every time i turn on my cnc controller the directions of the steppers change
from the settings i had

i am using
motion control products

4x drivers MSD542

3x power supply is PS407 40v 7a

any one got a clue
cheers guys

[irving2008]

Scott, Welcome to the forum...

can you clarify what you mean by 'the directions of the steppers change'? What software are driving this with and what Breakout board?

[Scott]

Scott, Welcome to the forum...

can you clarify what you mean by 'the directions of the steppers change'? What software are driving this with and what Breakout board?

ok so lets say i have just set up my machine runs fine cuts fine if i press left arrow key bed moves left and so on .. i finish the job and turn every thing off ..
but when i turn every thing on to start a new project and press the left arrow key it goes right or z goes up instead of down its random then i have to go into ports and pins and set the directions up again then it will run fine till i turn it off again its like it gets a power spike on startup that flip the direction on the steppers and its not always the save stepper that need sorting

all motion control products stuff Breakout board ect
running mach 3

[Ross77]

I've only just atarted useing Mach 3 so I'm no expert, but have you settup a new profile? if so you could try the default mill profile as a test to see if the same problems happen, if you havent then it could be Mach trying to overide your changes to the default?

I had all sorts of gremlims when I started, like forgeting to apply or save changes to the settings. Works fine now I'm used to it....

[Scott]

I've only just atarted useing Mach 3 so I'm no expert, but have you settup a new profile? if so you could try the default mill profile as a test to see if the same problems happen, if you havent then it could be Mach trying to overide your changes to the default?

I had all sorts of gremlims when I started, like forgeting to apply or save changes to the settings. Works fine now I'm used to it....

thanks i will check it out but i think it would change more than the direction of the stepper if that were the case i know its saved my settings as i added a rotory table and i know the setting were correct then when it saved cheers

[Owen.gray]

Hi could you please let me know what mottors you are using as if thay are 6 wire then you may have got youre wires confused double check youre mottor wireing

[ptjw7uk]

Hi Scott,
I would check the voltage applied to the direction output for the individual axis on the breakout board.
ie if you have to change the direction on an axis measure what the direction pin has changed to, note the reading ,high or low, power off then on again and see what the reading is now. I am not sure how mach3 works at power up will it put a pin high.

I thought the normal thing if the stepper was going in the wrong direction was to swap one of the pairs of wires over, I am not sure in what state the pins would be when you power up in my view they would normally all be low.
POINT to remember if you change the wires to the steppers TURN the power off first as you could blow the drivers.
If in doubt you ask a question on the mach3 forum.

Peter

[irving2008]

I think the point here is that Scott is not saying they are running in the wrong direction, but that the setup changes from one power up to the next, which sounds to me like Mach3 is not saving the configuration correctly or its being overwritten OR very remote possibility there is some earth loop or other interference which is cause the drives to misbehave..

Scott - when you go back into the ports tab are the settings changed or are they missing completely... i.e. the default MACH3 state? Have you defined a machine specific profile and select that each time when you start MACH3 (or is MACH3 starting with a defaul profile - does it have /p in the shortcut you start it from?) - see page 2-7 of the MACH3 manual. (sorry if you've been round that loop, but we all need to get to the same starting point)

[Scott]

I think the point here is that Scott is not saying they are running in the wrong direction, but that the setup changes from one power up to the next, which sounds to me like Mach3 is not saving the configuration correctly or its being overwritten OR very remote possibility there is some earth loop or other interference which is cause the drives to misbehave..

Scott - when you go back into the ports tab are the settings changed or are they missing completely... i.e. the default MACH3 state? Have you defined a machine specific profile and select that each time when you start MACH3 (or is MACH3 starting with a defaul profile - does it have /p in the shortcut you start it from?) - see page 2-7 of the MACH3 manual. (sorry if you've been round that loop, but we all need to get to the same starting point)

thanks for the help guys seem`s to be fixed now it must have been loose screws on breakout board i gave each one an extra little turn works fine now fingers crossed lol:whistling: