Need reassurance on motor calcuation

[hshrainey]

I have received some electrical drawings on a Industrial cabinet. I noticed on the 480v 3phase, they have 5 motors on a 30amp fuse. But
the motors ratings are as follows: 12.2A , 10.32A, 10.32A, .9A, and 8.39A. With the 125% I am seeing that it needs 60Amp fuse. Please advice.
Danke

Ron

 

[topgone]

I have received some electrical drawings on a Industrial cabinet. I noticed on the 480v 3phase, they have 5 motors on a 30amp fuse. But
the motors ratings are as follows: 12.2A , 10.32A, 10.32A, .9A, and 8.39A. With the 125% I am seeing that it needs 60Amp fuse. Please advice.
Danke

Ron

It's kinda hard to comment when it is not known how those equipment are designed to function. A built-in interlocking system or a functional grouping might allow a 30-amp fuse when the total calcs would tell you otherwise.

 

[Jraef]

Yep. Could be that they know that all of the motors cannot possibly run at the same time.

 

[kingpb]

Doesn't this fall along the same lines as why it is difficult to determine HVAC requirements and you have to follow the MOCP and MCA nameplate information provided by suppliers.