Importance of quality compounds for utility cable reliability

When unjacketed medium voltage (MV) extruded power cables were first installed in the late 1960’s, cable manufacturers and utilities expected them to perform reliably for 20 or even 30 years. History has shown that the service life of some of these early cables, whether HMWPE or EPR, could be improved. Since then, utilities in North America have demanded and obtained significant improvements in the performance and reliability of MV underground cables. Improvements in insulation cleanliness and resistance to wet aging, in semiconductive shield smoothness and cleanliness, in cable manufacturing processes, and in specifications and qualification test requirements, have all combined to deliver in modern cables expected service life exceeding 40 years. As cable demand increases, and some utilities are considering off shore cables, it is important to insure that these cables use quality compounds and consistently meet the specification and qualification requirements to insure that these hard earned gains in cable reliability are not sacrificed.