Re: Brushless Servo - VR Stepper - Difference?

Joe,

Other than having a stator and a rotor, not much. A brushless DC
motor is a DC brush motor turned inside out. What was the armature
winding is now the stator and the magnet rotates instead. What is
lost is electromechanical commutation (brushes, commutator) and is
replaced with rotor position sensors, usually hall-effect devices.
These send feedback to the drive so it "knows" which windings should
be energized.

A variable reluctance (VR) stepper has two coils just like a
permanent magnet, hybrid step motor (standard step motor). VR
steppers nearly extinct because PM hybrid steppers hold many
advantages over the VR variety.

Mariss

--- In CAD_CAM_EDM_DRO@y..., "onecooltoolfool" <joevicar3@i...> wrote:
> What's the difference between a VR stepper and a brushless servo?
> I have a VR stepper cut in half on my desk. Looks an awful lot
like
> the pictures of brushless servos I've seen.
> Give a clue to the clueless.
> Joe V.