multiple cranes/ one circuit

[Copperclad]

Hi all!
Just wondering if anyone here is "tight" on ART 610?
We are installing 480 volt 3 ph power to multiple cranes (hoists)on one common circuit. Im having some trouble understanding the demand factor.
We have 8 cranes that pull 2.5 amps each. I am wondering how to fuse this common feed and what wire size wire would be suitable?
I appreciate any help ya'll can give.

 

[LarryFine]

Simply (2.5 x 125%) + (7 x 2.5) I would think.

 

[Copperclad]

well,,,

well,,,

610.14 (e) is showing a demand of 0.78 for 7 cranes.
I assume over 7 cranes would still be 0.78?
Im thinking 2.5 X 8 = 20X.078=15.6
So you cant go over 15.6 amp OCP so a 15 amp ckt is fine?

 

[Copperclad]

to add

to add

I must add,,,,none of the cranes are continuous loads.......only a minute or so per hour.....