Contact US

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

NEC 480VAC Outlet Disconnect?

NEC 480VAC Outlet Disconnect?

NEC 480VAC Outlet Disconnect?

I am having a lot of trouble with this one:

The company I work for has multiple 480VAC receptacles around the building in our lab areas. We use them for multiple applications which include running motors, servo drive test panels, transformers, ect. They in a conduit “network” on the wall acting as regular wall receptacles without any disconnect means besides their breakers located in the warehouse area of the building.

What I have been tasked to do, is figure out if what we have is legal according to NEC. Do we need a disconnect on each of them, or is it just a good idea to have a disconnect? I know 430.109(f) says
“For a cord-and plug-connected motor, a horsepower-rated attachment plug and receptacle having ratings no less than the motor ratings shall be permitted to serve as the disconnecting means.”
The problem with that is we are not always running motors, we run a variety of different equipment, plus the fact that our connectors are just standard hubble plugs/receptacles, they are only marked with voltage phase and amp ratings.

I personally don't like the idea of plugging or un-plugging anything with 480 potential on it, loaded or not.

Any ideas? I can’t take another minute with my nose and fingers in the code book..

RE: NEC 480VAC Outlet Disconnect?

I'm not aware of any NEC requirement for a local disconnect on 480 V receptacles. I would recommend it, but not aware of any NEC requirement.

The Meltric units might be a possible solution (no interest in the company).



Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close