Hello Fellow CNC Machinists.
I am trying to calculate what size Amp Breaker / Size circuit would be recommended for a new CNC Machine I am trying to get.
We have 208/120 Y type 3 phase power at our electrical panel. (60hz of course)

The CNC router would have an HSD 9.0Kw spindle, and three 1.3Kw servos, as well as an 850watt servo on the Z axis...
So my calculations are 9000 + 1300 + 1300+ 1300 + 850 = 13750watt PLUS electronics.
Is it safe to say 15Kwatts?

Now, I have been told that servos can momentarily draw more power (unlike steppers) up to 350%...
So, how much power/reserve should I plan for?... maybe 18Kwatts?
That I think would be 50A circuit (208v * 50a * 1.7 = 17992 watt )

Can someone tell me if I am OK on these calculations?...

I know many would say - "ask your electrician" But I have found that most of them are lost on any of this spec/theory stuff, and mostly just read the label, and hope it's right...
I have often asked these type of questions and they are stumped, because they hook things up, doesn't make them engineers.
I am just hoping someone knowledgeable can guide me with their wisdom and reasoning.

Thank You in advance.

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