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Is this normal when moving by hand, i feel two notches/bumps/lumps mid way and two at each end. To start of with o thought it might be a defect on the rail where the bearing runs on, but the gap apart makes me think it's mechanical, possible where the poles line up?? Regards
alfawise u30
longer 42BYGH40H-2-19D
KH 2018 12 20
Back EMF can "brake" the stepper due to the driver's FET. Normally not repeatable as to location. To eliminate, unplug the motor so no back EMF can get to the driver.
Hi, these are being turned by hand, i forgot to add. Almost feels like every few inches, happens 3 times from the length of a x axis, but the other do it as well.Quote:
Originally Posted by TommyDee
Yes, I am aware of your description.
The energy your manual input generates makes the stepper generate electricity.
And the electricity you are generating is dumped into a short if the state of the FET is right.
The idea is regenerative braking but not in a controlled manner.
But in this case, the FET's gate is energized by the incoming power and this energizing of the FET also shorts the motor.
This is an electric brake. Then the energy holding the gate energized disappears and the short opens...
Again, you can disconnect the motor and remove all back EMF effects to see if that is what you are dealing with.
If the mechanical resistance is still present, then yes, it is most likely mechanical.
This is normal with all my printers. They all exhibit what you describe. Disconnect the motor... smooth as butter.
Thank you, sorry I did put in my first post turned by hand, I forgot I had put that. Thank you for your great in-depth explanation.