X-Ray Equipment 660 vs 517

Status
Not open for further replies.

mshields

Senior Member
Location
Boston, MA
There appears to be a conflict between 660 and 517 regarding the sizing of an X-Ray feeder sizes. I'm wondering if I'm missing some nuance.

660.6(B): indicates that the rated ampacity of conductors and overcurrent devices fo a feeder for two or more branch circuits shall be 2 times the momenatary of the two largest equipment plus 20% of the momentary of all other machines.

517.73 Rating of Supply Conductors and Overcurrent Protection, (A)(2) indicates that feeders and overcurrent protective devices shall be 50% of the momentary for the lartest, plus 25% of the momentary for each one after that plus 10% of the momentary of the rest of the machines.


Do you agree that these are in direct conflict?

Thanks,

Mike
 

steve66

Senior Member
Location
Illinois
Occupation
Engineer
Article 660 is for a non-medical, non-dental xray machines.

517 is for xray machines for medical and dental purposes.

Completely different animals.

Medical Xray equipment always produces short pulses to limit exposure to xrays. Not necessarily so for industrial xray machines.

So if its a medical xray, follow 517. If its another type of xray, follow 660.
 
Status
Not open for further replies.
Top