Article Courtesy of Prysmian Group

Prysmian is widely known as the world’s largest cable manufacturer, born out of the merger of Pirelli, General Cable, and Draka. What is not as widely known is that Prysmian has been a manufacturer of underground cable accessories for over 40 years and its accessories have been used on many of the largest energy infrastructure projects across the globe. Being a technology leader in development of both cable and cable accessories provides Prysmian with a unique perspective that inherently focuses on the performance of the overall cable system rather than the individual components in isolation

The Prysmian Elaspeed Splice (Cut Sheet Link, Video Link) is a great example of how this engineered approach has resulted in superior cable system solutions. When developing this splice over 30 years ago, Prysmian made a very simple observation that might be easy for a non-cable manufacturer to gloss over. The best cable system was one that consisted of one continuous length of cable with no splices. This observation led to a design approach that focused on rebuilding the cable over the splice point to replicate as closely as possible a continuous length of cable and thus replicate the cable performance. This extraordinary goal was realized in the Prysmian Elaspeed Splice, a revolutionary splice design which provides best in class cable system performance by following the stated MV Cable design criteria below:

Use The Same Materials Shown to Provide Excellent MV Cable Performance

The Prysmian Elaspeed Splice is insulated with EPR insulation, a common MV cable insulation, unlike competitor offerings which typically use Silicone Rubber insulations that are not used in MV cables. EPR has a vapor transmission rate that is 100 times better than Silicone Rubber which means that EPR provides substantially better protection against water/humidity ingress over the long term.

Use The Same Manufacturing Processes Shown to Provide Excellent MV Cable Performance

Prysmian Elaspeed Splices are produced like a medium voltage cable using a triple extrusion production system. The splice’s insulation system is made in long lengths (1000’s of feet) at a time on a vertical extruder to control dimensions to tight tolerances. Competitor splice offerings are molded and can have seams that lead to failures.

Use The Same Testing Shown to Provide Excellent MV Cable Performance

The Prysmian Elaspeed Splice’s insulation system is extruded in long lengths onto an aluminum rod which allows the entire length of insulation material to be tested for Partial Discharge and AC Withstand just like MV cable. This testing is in addition to the typical industry standard testing for splices. Most competitors only test to meet the industry standard for splices which does not require electrical testing on all splices.

Best In-Class Protection Against Water Ingress

It is well established that water ingress into MV cable and accessories can accelerate aging and lead to failures. The Prysmian Elaspeed Splice has passed external water pressure testing that far exceed the industry standards. The use of expanded EPR provides 30psi of internal pressure against the cable it’s applied to.

Leaders in the industry are beginning to recognize that taking a cable system approach that accounts for the interaction between MV cable and MV accessories is needed in order to improve overall performance. One such leader is the National Electric Energy Testing, Research, & Applications Center (NEETRAC) who recently presented a study on the “Endurance of Medium Voltage Joints under Laboratory Wet Aging Environments” (Link to Study Results). This study uses a methodology similar to the Accelerated Water Tree Test (AWTT) which is typically used for evaluating a single length of MV cable, only in this study it was applied to two (2) lengths of cable spliced together with various splice designs. The AWTT test looks at the AC Breakdown Strength of the cable (or cable system in this case) newly installed, at 120 days, and 180 days and is the most common accelerated test used in North America for MV cable. For comparison, industry standard testing for splices only lasts 30 days. The only splice design in this study that maintained the same AC Breakdown Strength as the Cable Only Control Group was a Cold Shrink, EPR Insulated Splice with Shear Bolt Connector (similar to the Prysmian Elaspeed Splice). All other splice designs had lower AC Breakdown Strengths that declined more rapidly over the 180 day test period. This study seems to validate Prysmian’s design choices and cable systems approach in developing the Elaspeed Splice.

For additional information on the Prysmian Elaspeed Splice or other Prysmian products, please contact your local Gresco Account Manager.