NEMA for VFD

[renovatio617]

i am designing a new system for circulation Toluene. my question is i have the VFD for the motor, and the VFD need to be in NEMA box , do i need to have Z-purge system to complies with NEC code ?

 

[ramsy]

No purging process is allowed in the motor enclosure. Nema enclosures must isolate the electrical equipment from other environments. Higher NEMA ratings are required for more severe environments.

 

[rbalex]

Both NEMA MG-1 and the NEC permit purging motor enclosures. See Section 501.125(A)(2) for a Class I, Division1 example. Section 501.125(B)(2) refers back to Division 1 for some Division 2 applications, if appropriate. Usually Division 1 identified motors are not required in Division 2; however, NEMA MG-1 does require the motor manufacturer’s input where their motor is used with a ASD (VFD) in a classified location.

However, I believe the OP was asking about the ASD (VFD) enclosure. It too may use a Type Z purge, assuming it is a Division 2 application.

 

[ramsy]

Thanks for the correction Bob. A response to bonding Hazmat warehouse racks may also need to be checked.
http://forums.mikeholt.com/showthread.php?t=187883&p=1872251#post1872251