Sizing a Generator

[augie47]

I hesitated posting this but thought I would out of curiosity.
Electrician has been asked to supply a generator to supply a 30HP 480v motor driving a rock-cut saw. Motor is across the line starting.
There are so many variables I told him to obtain ALL the specifics and then contact a generator manufacturer or the equipment manufacturer but then curiosity set in and I wondered if anyone has filed experience input.
,

 

[Ingenieur]

Kohller has a free, easy to use program

how frequently is it going to start/stop? Per hour
is it the only load on the genset?

wag 40-50 kva

 

[ActionDave]

1.5 kva x hp is what my motor guru says. How many starts is important needed info.

 

[Ingenieur]

Think you can get the sw here
http://www.tawinc.com/power-systems/resources/generator-sizing-software/

 

[steve66]

Kohller has a free, easy to use program

how frequently is it going to start/stop? Per hour
is it the only load on the genset?

wag 40-50 kva

Yes, I think Kohler, Cat, and Cummins all have sizing programs you can get. it will spit out one or more recommended generator sizes, with various combinations of recommended alternator sizes.

If you really want to make sure its right, its probably best to just let the sales rep. figure it out.