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. Both max at 24,000 rpm.
Is the torque curve significantly different? 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. Even if my current VFDs are not up to the task of driving a4pole motor at 800Hz a new VFD is not the largest part of the cost.