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I have a non manufacture project I need a stepper for but it's low torque
I'm just rotating a Lazy Susan but I need positional accuracy which I will use a opto sensor for so I have a home
I need to extend the cabling to maybe 2m, Pi forums they said not possible due to interference
I laughed
Just solder CY 4 pin cable and earth the shielding right?
0.5mm should be fine there's very little current
It would depend on if you're extending the stepper motor wiring, or the control signals to the motor.
To the drive, you might get some lost/additional steps, but I'm going to guess you don't need that precise a position, so probably won't be that much of a problem.
To the motor, worst issue would potentially be the stepper wiring causing noise in the opto sensor, causing false triggers when you're trying to home, however a bit extra load on the opto with a suitable resistor would soon solve that.
Quote:
Originally Posted by m_c
I do need the precision
It's Pi powered
I need to know where I am in the rotation at all time that's why I included a home, in case of power cut it also logs it's last position to the SDcard so it can auto recover on power up
We extend CNC to 2m all the time on routers with no issues so there must be a way
End stops I was going to use RF cable for although given it rotates there is no end....
I bought 4 core 0.5mm CY cable will use it for both stepper and end stop and ground them
So will see what happens
I know it's overkill for the end stop but I got 10m's of it so might as well use it
How much precision are we talking?
I'm only guessing this isn't something where you need to be back in the same position within seconds of angular rotation...
In all honesty, given it's only a Nema 14 motor, the voltage isn't going to be that great, and the amount of generated electrical noise isn't going to be that great either.
If rotational drift is a concern, then you could implement a position reset whenever the opto gets triggered.
0.1mm will be fineQuote:
Originally Posted by m_c
The rotational speed is very low <0.5RPM at maximum, geared 4.5:1 to give me 900 steps per revolution
I planned to check the position every rotation to see if it's drifting because why not?
I figured Opto sensor are touchless and probably the easiest solution to add something that rotates neatly,I can hide out of sight
An inductive sensor would look out place