On 4/11/2018 10:05 AM, Bob La Londe wrote:

Is there any significant advantage to an 800hz 4 pole spindle/motor over
a 400hz 2 pole spindle motor?

Both are rated at 1.5Kw.Â* Both max at 24,000 rpm.

Is the torque curve significantly different?Â* Would one have more net
power at lower RPM ranges than the other?

I'm thinking one of the next times I am cash flush I want to upgrade the
spindles in my little high speed machines to ISO20 quick change spindles
to make tool changes faster and be able to implement usage of the tool
height tables in my control software.

800Hz and 400Hz spindles are both relatively expensive in this
configuration, but the price difference is not huge.

At first glance one might think that a special VFD is required, but
there are some quite affordable VFDs capable of higher higher than 400Hz
output.Â* Even if my current VFDs are not up to the task of driving a
4pole motor at 800Hz a new VFD is not the largest part of the cost.


On 4/11/2018 11:22 PM, whit3rd wrote:
On Wednesday, April 11, 2018 at 10:05:22 AM UTC-7, Bob La Londe wrote:
Is there any significant advantage to an 800hz 4 pole spindle/motor over
a 400hz 2 pole spindle motor?


3 phase motors. Direction is determined by phase order. Swap any two
legs to reverse direction.

It seems whit3rd is not familiar with the high speed spindle motors I am
talking about.