×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

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!
  • Students Click Here

*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

Jobs

NFPA 79 or NEC

NFPA 79 or NEC

NFPA 79 or NEC

(OP)
This is an easy one - I am trying to get a full understanding of the requirements for power connected to an industrial 3 phase machine based on the machine data plate. I know that the data plate rated amperage is the sum of all of the motors at full load, but I also know that all of the motors cannot be run simultaneously. If my data plate says 100 Amps at 460V, but at no time do I ever get above 40 Amps during operation of the machine, am I still required to have a 100 Amp service supplied to the machine? Thanks in advance.  

RE: NFPA 79 or NEC

Does the nameplate say something like MCA (minimum circuit amps)?  If it does, then you must have conductors at least as large as the MCA rating.  The NEC requires you to follow the manufacturers nameplate, hence the UL listed configuration.

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!


Resources