Category Archives: Workmanship
Each year, millions of people and thousands of businesses are impacted by underground cable system failures. IMCORP is dedicated to advancing the understanding of how these failures occur and more importantly, how they can be avoided.
Jun 09 2017
Termination Damaged but Passed by VLF Test
By: Ben Lanz and Bill Corrente
Posted in: Workmanship, Wind, Utility, Solar, Renewable, Generation
Termination Damaged but Passed by VLF Test Our utility client asked us to commission cable systems at a new generation facility after experiencing several termination failures. The installation contractor had already tested the cable syste... Read ArticleOct 27 2015
Low Signal Magnitude (pC) but Serious Cable Defect
By: Ben Lanz and Bill Corrente
Posted in: Workmanship, Wind, Utility, Renewable, Cable
While commissioning new generation project in the multiple defects were identified within the cable system. One particular cable exhibited defects in the dozens of low magnitude partial discharge signals at two times the operating voltage. Th... Read ArticleDec 18 2014
Wind Farm Cable with a Small but Very Serious Defect
By: IMCORP
Posted in: Workmanship, Wind, Renewable
After performing an initial Factory Grade® assessment at a renewable energy plant, a cable was found to have near end termination discharge at operating voltage. The on-site crew attempted to mitigate the Partial Discharge (PD) activity by disa... Read ArticleJul 30 2012
Stone in Cable 176m (578ft) from Termination
By: Ben Lanz and Bill Corrente
Posted in: Backfill, Cable, Facility, Generation, Renewable, Solar, Utility, Wind, Workmanship
IMCORP’s Factory Grade® assessment discovered a substandard location while commissioning the cable systems at a generation facility. The client used IMCORP’s Location Matching service to pinpoint the defect location. N... Read ArticleJul 23 2012
PD Activity in a Y Joint at a Nuclear Facility
By: IMCORP
Posted in: Workmanship, Generation
IMCORP conducted its Factory Grade® assessment on a critical loop at a government nuclear facility in southeast USA. This particular PD occurred at a Y-joint located 185 ft. and had an inception voltage of Uo. PD a... Read ArticleApr 16 2012
Non Radial Cutback on a Cold Shrink Joint at a Wind Farm
By: IMCORP
Posted in: Workmanship, Wind, Generation
This cold shrink joint was a part of a feeder cable system at a wind farm site that failed to pass IEEE 404 specifications. Even after the Factory Grade® assessment found this joint to be substandard, the cable system's contracto... Read ArticleApr 16 2012
Misplaced Stress Relief Material at a Utility
By: IMCORP
Posted in: Workmanship, Utility
This particular open-air termination transitions an underground line to a riser. Although visual inspection indicated that the cable was properly installed (it is difficult to see the mastic placement with the termination installed), the cable ... Read ArticleMar 27 2012
Semicon Defect During Installation
By: IMCORP
Posted in: Workmanship, Wind, Generation, Cable
The cable displayed here was compromised as a result of a semicon cutback error that was not recognized as a defect by the installer. When the cutback was made, the installer created a slight spiral instead of a radial cut leaving a thin slice of... Read ArticleMar 23 2012
Issues Performing Cutback on Out of Round Power Cable at a Wind Farm
By: IMCORP
Posted in: Workmanship, Wind, Generation
Featured here are medium voltage feeder cables at a wind farm substation in South Dakota. These cables are the site’s most critical link, handling the output of 10 to 20 turbines. IMCORP Factory Grade® technology found that ... Read ArticleMar 23 2012
Improper Heat Shrink Application
By: IMCORP
Posted in: Workmanship, Wind, Generation
These images show the development of a medium voltage cable failure in an open-air heat shrink termination. The first image (left) shows the IEEE 48 non-compliant heat shrink at the termination that was located by the IMCORP's Factory ... Read ArticleMar 23 2012
Power Cable Degassing
By: IMCORP
Posted in: Workmanship, Wind, Generation
These images show cross-sections of a medium voltage power cable that was installed at a wind farm in Wyoming. In this case, the IMCORP Factory Grade® technology indicated partial discharge activity on a section of cable. The PD l... Read ArticleMar 23 2012
Cable Manufacturer Defect During Repair
By: IMCORP
Posted in: Workmanship, Wind
IMCORP's Factory Grade® assessment indicated a PD site in an underground medium voltage power cable. Initial inspection of the PD site did not show any evidence of an issue. According to the latest study no visual evidence is reported ... Read ArticleMar 23 2012
Whittled Cutback on Power Cable at a Co-op Utility
By: IMCORP
Posted in: Workmanship, Wind
This image shows a 7.2 kV (medium voltage) power cable system at a co-op utility in rural Missouri that supplies power to a residential area. IMCORP's Factory Grade® assessment indicated PD activity at the separable connector... Read ArticleMar 23 2012
Power Cable Termination Cutback Issues at a Data Center
By: IMCORP
Posted in: Workmanship, Facility
Pictured here are live front terminations of a medium voltage power cable system at a critical data center in Portland, OR. After termination failures began to occur, DC HiPot testing had been utilized but came back inconclusive. At this po... Read ArticleMar 23 2012
Power Cable Insulation Damage (Sabotage) at a Wind Farm
By: IMCORP
Posted in: Workmanship, Generation, Cable
The discovery of this medium voltage power cable defect at a site in Canada provided an opportunity to demonstrate the effectiveness of IMCORP’s cable diagnostics. On a cable of over 1400 feet, IMCORP was able to locate the defect within si... Read Article