I see in this photos they are wrapping the stepper wires around a coil
I assume to prevent any jitter or interference
Do you guys know what this is called?Attachment 7886
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I see in this photos they are wrapping the stepper wires around a coil
I assume to prevent any jitter or interference
Do you guys know what this is called?Attachment 7886
I'm not sure what you're asking. What are the coil things called? Those are toroid cores. They're likely added as part of getting emissions for a commercial product reduced to the level needed for something like FCC Part 15 compliance or UL listing.
It is an EMI ferrite core.
You can get large ones like that to wrap the wires around, or you can get smaller ones that clamp around the wires.