sizing OCPD for HVAC fans 1

[Mauriciocol]

I am reviewing somebody else's design and I want just to be right in my decisin since I haven't work designing protections for at least 10 years. The situation is this:
I have a general protection specified as - 225AT - 225AF in a dedicated CB panel rated 225A-240V.
It feeds an MCC and one Light/Power panel (50A). the MCC feeds two pumps 1/2 HP each, one 40HP and a 15HP fans. The OCPD devices for the fans are 100A magnetic for the 15 and 175A thermomagnetic for the 40.

I have not found problems with the design but since I haven't done this in a while iwant to confirm this is a valid design as per the NEC.

Thanks for your help

 

[jbartos]

Suggestions marked ///\\I am reviewing somebody else's design and I want just to be right in my decisin since I haven't work designing protections for at least 10 years. The situation is this:
I have a general protection specified as - 225AT - 225AF in a dedicated CB panel rated 225A-240V.
///What is the 240V system, three phase or single phase three wire?\\It feeds an MCC
///What is the MCC bus rating?\\ and one Light/Power panel (50A). the MCC feeds two pumps 1/2 HP each, one 40HP and a 15HP fans.
The OCPD devices for the fans are 100A magnetic for the 15 and 175A thermomagnetic for the 40.
///The sizes of protective devices suggest some form of the soft starting arrangement. If it is not the case, they will be needed for starting the 40HP motor. Definitely, 225A panel will not be able to support simultaneous DOL motor starts.\\I have not found problems with the design but since I haven't done this in a while iwant to confirm this is a valid design as per the NEC.
///Please, notice that some manufacturers offer MCCs from 600A, 800A, etc.\\

 

[Mauriciocol]

Jbartos
thanks for your reply.
The system is a 240 3 phase. My thake is that the MCC bus should be at least 400A (in the design it is not specified).
What other aspects of the design should I be aware of?

I really apreciate your help

 

[jbartos]

Suggestion: If the process requires the simultaneous start of 15HP and 40HP motors, DOL, the service should be increased to 400A, 240V, 3-phase. However, the MCC come with 600A buses, normally. It can be made 400A by a main fusible switch or circuit breaker. Visit

http://www.directindustry.com

and search for Motor Control Center
which will return MCC manufacturers.
Also, visit

http://www.thomasregister.com

and type Centers: Motor Control under Product or Service, which will return 34 companies to approach to

 

[Mauriciocol]

thanks a lot jbartos I will check those sites and check as per your recommendations
you have been very helpful