Re: 5-Phase steppers

--- In CAD_CAM_EDM_DRO@yahoogroups.com, Tony Jeffree <tony@j...>
wrote:

> At 19:28 19/01/2005, caudlet wrote:
> >5 phase steppers run smoother...<snip>
>
> I'm afraid you're in danger of descending into advertising speak

here. You

> fail to answer the question begged by this statement -

i.e., "smoother than

> what?".
>
> If you mean:
>
> a) Smoother than a 2-phase stepper motor driven in full or half

step, or

>
> b) Smoother than a bag of spanners (wrenches to the

transatlantically

> challenged),
>
> then I would agree with you.
>
> However, if you mean:
>
> c) Smoother than a 2-phase motor driven by a good bipolar

microstepping drive,

>
> then I would strongly disagree.
>
> 5-phase steppers made sense when they were superior to full/half

stepping

> drives and at the same time an economical alternative to the then

expensive

> microstepping drives. Since the arrival of good quality

microstepping

> drives at very reasonable prices (e.g., Gecko, to name but one),

the

> economic justification doesn't exist anymore.
>
>
> Regards,
> Tony

On a one for one basis (motor VS motor) the five phase motors have
more poles closer together. This results in two things. They have
less distance to move (the ones I have in my "wish" cabinet are .72
deg per step) which results in less vibration and noise and takes
less power to pop the motor to the next pole. This also translates
to true resolution enhancement. Now, if you want to talk about
drives it's true that smoothness is much better with the
microstepping bipolar drives but if you just were to be able to do
1/4 stepping with a 5 phase you would be up to a microstepping
level. There is no USA economic justification to run 5 phase motors
(the reason I have 8 beautiful Berger Lahr 34 frame motors in storage
and run 2 phase on all my stepper machines with Gecko's), but the
person posting was not in the US and the availability and price of a
lot of things we use here are more problematic to them. Berger Lahr
is a German company and his posting looked to be from that part of
the globe.