Results 1 to 9 of 9

Thread: Temporary MV Cable Type

  1. #1
    Join Date
    Oct 2008
    Posts
    673

    Temporary MV Cable Type

    Does anyone have any recommendations for a type of cable to use for a temporary (6 months) installation? On LV installation I've always seen S.O. cable used so I was curious if there was a similar S.O. equivalent for MV cable? System is a 4.16kV system.

    The cable will only be used for emergency purposes (connecting emergency generators) but if it is put into use it must carry approx. 2000A. I'm looking for the best economical solution for a temporary cable since it will only be used for a short duration of time.

    Temporary cable will be run in free air

  2. #2
    Join Date
    Jul 2007
    Location
    Clark County, NV
    Posts
    1,098
    The NEC defines three types of "temporary:" during construction, 90 days, and emergencies/tests [590.3]

    Services must be installed as if permanent [590.4]. Don't know enough to know what this counts as for you.

  3. #3
    Join Date
    Jan 2016
    Location
    PA
    Posts
    5,697
    you are talking about 15 MW of power
    imo this sounds like a very complex project
    is there an engineer involved?

    you might look at mining duty cable
    or doing your permanent install upfront
    The difference between genius and stupidity is that genius has its limits.

  4. #4
    Join Date
    Jan 2011
    Location
    United States
    Posts
    7,421
    Unshielded red EPR comes provided people will not physically touch the cable.
    I'm in over my head...

  5. #5
    Join Date
    Jun 2017
    Location
    WI, USA
    Posts
    362
    Quote Originally Posted by MAC702 View Post
    Services must be installed as if permanent [590.4]. Don't know enough to know what this counts as for you.
    A worthy highlight, as depending on type of building and function there may be 2-hour ratings to consider.

  6. #6
    Join Date
    Oct 2008
    Posts
    673
    Thanks for the replies.

    We've decided to treat this as a permanent installation and run MV-105 cable in cable tray.

    Does a cable tray require a cover for MV cable?

  7. #7
    Join Date
    Jun 2017
    Location
    WI, USA
    Posts
    362
    Quote Originally Posted by philly View Post
    Thanks for the replies.

    We've decided to treat this as a permanent installation and run MV-105 cable in cable tray.

    Does a cable tray require a cover for MV cable?
    Tray rating for cable, yes. Tray cover, no. In some cases you might consider fire wrapping them.

  8. #8
    Join Date
    Oct 2008
    Posts
    673
    Quote Originally Posted by publicgood View Post
    Tray rating for cable, yes. Tray cover, no. In some cases you might consider fire wrapping them.
    I wasn't aware that some cables have specific tray ratings?

  9. #9
    Join Date
    Jun 2017
    Location
    WI, USA
    Posts
    362
    Quote Originally Posted by philly View Post
    I wasn't aware that some cables have specific tray ratings?
    392.10. It must be listed for use in tray. There are concerns on crushing the cable, for instance. This listing must be printed on the cable.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •