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


Power One-Line Requirement?

Power One-Line Requirement?

Power One-Line Requirement?

We have many remote, unmanned, compressor sites. The voltages from from 3Ph 480V to 240/120 (most are single phase 240/120).
Are One-Lines required by some governing body (OSHA perhaps?)?

Is there anything in NFPA XXX stating one "shall" be required to have such an animal? If so, is there some voltage level threshold?

Any and all input is greatly appreciated!

RE: Power One-Line Requirement?

For OSHA [written by legislatures and administered by bureaucrats], most requirements 'implicit' not 'explicit'. Don't look for any rational guidance for your minimum compliance [/rant off]

Your question actually is; can a reasonably competent emergency responder understand the shut-offs necessary to render your site 'safe' without undue effort and significant circuit-tracing? If there is a labeled, prominent OFF switch that will 'render safe' the site, I think that is enough. On the compressor stations I've been in, that is impossible. So post a rudimentary 1-line that will show the Fire Captain / Elec. Lineman what needs to be shut down to 'render safe'.

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!


White Paper - Effects of AIA Quick Guide to UL 489 or UL 1077
The function of a circuit breaker is to provide overload (thermal) and short-circuit (magnetic) protection to a circuit and its downstream components. A circuit breaker functions like an airbag in a car, protecting circuit components and people by tripping the circuit to interrupt the current flow if it detects a fault condition in the control system. Download Now
White Paper - Guide to Integrate Large-Format Additive
As with any new technology, getting into large-format 3D printing begins with investigation. The first question may be a simple one: what does “large-format” mean? For 3D printers, “large” is a relative term. Many extrusion-based (FFF) 3D printers are referred to as desktop machines, because they fit on table space. Some of these have very respectable build volumes – but when it comes to “large-format,” the machines will need their own dedicated floor space. Large-format 3D printers have significant build volumes and are most often found in professional settings, like manufacturing facilities and R&D centers. Download Now

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