×
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

I.S. and Power Cabling Segregation

I.S. and Power Cabling Segregation

I.S. and Power Cabling Segregation

(OP)
Hi,
My attempts to find an answer on the net has not been successful. Any assistance would be appreciated.
What I am after is:

What is the minimum distance required between an intrinsically safe/instrumentation cable and 440V AC power cable.  Also what should be the minimum spacing between a 6.6kV power cable and the other two?

Thank you.

RE: I.S. and Power Cabling Segregation

Industry practice allows for a separation of 300mm in all cases stated.

RE: I.S. and Power Cabling Segregation

There is no hard and fast rule on spacing and its more of a question of choice and judgement, however practices in the petrochem industry allow for 150mm spacing between all instrumentation cabling and LV power cables (ie upto 100V) and 300mm between instrumentation cables and HV (ie above 1kV)cables. The practice does specify the use of screened instrumentation cables throughout.

RE: I.S. and Power Cabling Segregation

I have been required to to have a minimum of 500mm air gap between IS and non-IS wiring. However, it was allowable to have a solid barrier with an equal amount of creepage distance between them. This was a North Sea application, DNV specs I think.

RE: I.S. and Power Cabling Segregation

The NEC says:
"504.30 Separation of Intrinsically Safe Conductors.
(A) From Nonintrinsically Safe Circuit Conductors.
(1) Open Wiring. Conductors and cables of intrinsically safe circuits not in raceways or cable trays shall be separated at least 50 mm (2 in.) and secured from conductors and cables of any nonintrinsically safe circuits.
Exception:  Where either (1) all of the intrinsically safe circuit conductors are in Type MI or MC cables or (2) all of the nonintrinsically safe circuit conductors are in raceways or Type MI or MC cables where the sheathing or cladding is capable of carrying fault current to ground."

Don

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