National Electrical Installation Standards

Standards as High as Your Own

Monday, September 9, 2019


How to splice 500 MCM in the middle of a 200 yd placement. They did a direct burial, this is in Cambodia. The cable was damaged by an excavator

Daniel Henry


Hey Daniel thanks for your question. A warning ribbon installed above the direct buried conductors might have helped avoid that from happening so is something to consider for future installations and for this repair. Waring ribbons are required for underground service conductors, under the conditions given, as stated in 300.5(D)(3). Splices are permitted underground without boxes as stated in 300.5(E). The splices must be listed for that use as stated in 110.14(B) and are available for both individual conductors and multiconductor cables with an overall jacket. Similar rules are in place for over 1000 volt applications as stated in 300.50(D). Depending on how much of the conductors are damaged multiple splices and additional short conductors might be needed.

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