×
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

Abandoned Underground Power Cable at Station

Abandoned Underground Power Cable at Station

Abandoned Underground Power Cable at Station

(OP)
HI all,

Can someone share your practice of dealing with abandoned underground feeder cables from substation to raiser poles on street, which the cable cannot be pulled out due to the ruptured ducts.

Thanks

RE: Abandoned Underground Power Cable at Station

If junk price of copper in the cable is less than cost of excavating the cable, cut it off at each end and abandon in place.

RE: Abandoned Underground Power Cable at Station

NESC: "Lines and equipment permanently abandoned shall be removed or maintained in a safe
condition."

So abandoned lines are not truly abandoned, they must still be maintained.

RE: Abandoned Underground Power Cable at Station

(OP)
rcwilson, should or shouldn't be grounded at each end?
stevenal, the cable cannot be removed without big excavation work due to the rupture of the duct somewhere don't know.

RE: Abandoned Underground Power Cable at Station

Adverise for free copper to anyone who can pull it out.

RE: Abandoned Underground Power Cable at Station

Steven brought up a good point. In our work we abandon direct-buried temporary construction power cables under the completed power plant. Removal would require a lot of excavation. Cables are cut off a few feet below the surface and the area backfilled so there are no accessible ends. The cable route is shown on the client's as-built drawings.

Coming out of a substation, there may be a concern about transfered GPR potentials during a ground fault if you ground the cable at either end.

RE: Abandoned Underground Power Cable at Station

I would earth both ends if possible. That gives you some chance of being able to use an inductive coupler to trace the cable at some point in future.

RE: Abandoned Underground Power Cable at Station

If the duct damage has also damaged the cable, or if you are able to intentionally pull the cable hard enough to damage it where the duct is damaged, it may be possible to locate the damage with a Time Domain Reflectometer.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Abandoned Underground Power Cable at Station

If the cables are multicore & you can expose the ends of cores,
try pulling the cores out one at a time with a Tirfor Winch similar device.
It worked for a scrap copper thief that pulled the 120mmm2 copper cores out of a redundant underground swa cable.
Mind you, he had a steam locomotive at his disposal!

RE: Abandoned Underground Power Cable at Station

(OP)
Hi gattie, that is interesting LoL !
Thanks

RE: Abandoned Underground Power Cable at Station

Try a D-9
"There are no jobs to big, just machines that are to small."

RE: Abandoned Underground Power Cable at Station

Not sure about your local requirements, though in AU, AS3000 requires they are treated as live.

Regards,
Lyle

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