The NEC says that 3'-6" clearance is required for a 480V panel to any grounded parts table 110.26(A)(1) : Condition 2. Would grounded include the SIDE of a motor control center? I have a switchboard on one side of a room and a VFD on the other - both facing each other and both 480V. There is 20' between them. I would like to add a motor control center in the middle of the room facing one of the side walls. The MCC is 13' long - this leaves 3'-6" from the sides of the MCC to each of the VFD and switchboard faces. If the sides of the MCC are considered grounded then 3'-6" is fine if the sides of the MCC are considered exposed live parts then I need 4'. I am attaching a picture to describe the layout. Thanks in advance.
Working Space Requirements
- Thread starter mpicco
- Start date
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mdshunk
Senior Member
- Location
- Right here.
No exposed live parts if the MCC is in a cabinet. Not so many live front (or side!) MCC's being installed nowadays. :smile:
- Location
- Lockport, IL
- Occupation
- Semi-Retired Electrical Engineer
If you cannot unscrew the side cover of the MCC and see energized busbars, then you are in Condition 2. If you can unscrew the side cover, and if that gains you access to the bus bars, then you are in Condition 3.
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