Future Proofing Cable Installations and Training
By Mark Franks, AVO Training Institute Senior Consultant
It is well documented that the cable installations in the United States are experiencing significant “service aging”. This is evident in studies conducted in power utility, municipal power and private sector cable installations. The results indicate that over 50% of all cable related outages are a caused by poor workmanship in the original installation of the cable. Splice failures make up the majority of these outages. It is evident that industries utilizing medium voltage power cables take steps ensuring that cable systems are “future proofed” minimizing service outages and costly cable replacement.
Assume that appropriate cables and ancillary products have been selected during the design of the system, and that existing installations were given the same consideration at the time previous selections were made. With this consideration, are led to three major training gears
driving the “future proofing” mechanism; cable splicing and terminating, cable fault location and tracing, and diagnostic testing of cable systems.
2 Cable Splicing and Terminating Training
Training for technicians, linemen and electricians involved in placement of medium voltage cable systems is fundamental in the “future proofing” process.
Technicians should be trained in the latest techniques in cable handling, splicing and terminating to ensure all new installations are devoid of the “historical” problems that have plagued the cable industry. Some of these issues are excessive bending radius, over tensioning cables, prepping issues and cable cleaning during splicing and terminating. Most splices and terminations come in “kit” form and include instructions for assembly of the products. The missing element in this process is how to actually prep the cable package to the dimensions required. Most of this information is either handed down technician to technician or learned using the self-taught method. Without instruction and practice, “critical” steps in the cable prepping and splice assembly process are unknowingly overlooked by the technician. This builds in known failure mechanisms into the cable system, some that may take years to develop into failures!
Training is also critical for service restoral personnel when repairing existing cable systems that have experienced failure. Many times personnel will be splicing or terminating in environments that create contamination in the splicing process. Training in environmental control, cable prepping, and splicing techniques ensures that cables are properly repaired, tested for insulation integrity and placed into service with the confidence that the cable system will provide quality service throughout its remaining life expectancy.
Cable placement crew personnel often place the cable but are not involved in the splicing and terminating efforts. This is common in contract placement projects. Often cable damage is experienced in the pulling operations the will ultimately cause the cable to fail. This type of damage is not readily apparent and most of the time is not sever enough to be exposed during testing. The long term result of these issues result in costly outages and cable replacement. Many times the same types of issues are rebooted into the system by the same personnel installing the cables as before without the knowledge that they are creating cable failure mechanisms. Cable installation and handling training is a key element in “future proofing” the cable system.
3 Cable Fault Location and Tracing Training
Cable Fault Location methods have been in the industry for many years. Studies have proven that cable fault location equipment used incorrectly can trigger failure mechanisms in service aged cable only to cause more costly outages in the near future. Modern cable fault locating technologies, used properly, provide the ability to locate cable failure points without creating these issues providing the technician knows and operates the equipment proficiently. With the microprocessor age well embedded in cable fault location equipment and most of the equipment highly automated via the use of custom software, technicians must be proficient in the use and operation of the equipment. Interpretation of findings and understanding the technologies involved in cable fault location is a must in order to achieve the desired results.
Modern cable tracing and identification equipment can be employed to minimize outage times and restoral efforts by accurately identifying cable circuits, routes and depths. The fault locating process relies on accurate cable location as well for safe, efficient location. Again, as in fault locating equipment, cable tracing equipment can be somewhat complex without proper training and instruction in its use.
Cable identification, fault locating and tracing is by nature an integral part of the “future proofing” process. Older service aged cables offer an opportunity to create failure mechanisms or hasten the growth of these mechanisms when cable fault locating equipment is not used properly by trained personnel.
4 Cable Testing and Diagnostic Training
One of the most difficult questions concerning power cable maintenance is “How Long Will it Last”? This question has plagued the industry for years and has led to the costly replacement of cables without justification and also repair of cable systems that were so deteriorated that they simply failed again causing more outages.
Today, the test equipment industry, along with cable manufacturers and industry standards agencies have developed testing standards and test methods with high-tech equipment to diagnose cable insulation condition. This is enabling the industry to prolong cable replacement, lower costs, reduce outages and overall plan cable expenditures thus “future proofing” the cable systems.
Cable diagnostic test equipment and analysis is by nature somewhat complex and requires technicians to be trained to a much higher understanding level than in the past. Miss-diagnosis costs money and many times lots of it! Technicians have to be expert in cable diagnostic equipment and software as well as an in depth understanding of cable and failure mechanisms.
5 AVO Cable University and Cable Technician Certification
With the critical issues facing the utility and industrial cable industry, it is imperative that training as well as test equipment technology be applied to existing and future cable installations to ensure “future proofing” for improved cable reliability. AVO Training Institute continues to meet the industry needs by providing a comprehensive vehicle to “future proof” cable systems for increased reliability and reduced costs.
AVO Cable University provides training in the three critical areas of the “future proofing” process for new and service aged power cables:
- Cable Splicing and Terminating Medium Voltage Cables--- a comprehensive, hands-on course providing technicians with the skills and knowledge along with practical experience to successfully complete tape, cold shrink, heat shrink and molded technologies of splicing and terminating medium voltage solid dielectric cables. The i’s are doted and the t’s and crossed to ensure the technicians understand the methods and well as common mistakes that lead to failure in splices and terminations.
- Cable Fault Locating and Tracing--- With the completion of the AVO Cable University cable training complex, AVO now has one of the largest and most comprehensive cable training fields in the industry. Cable tracing, fault locating, testing, safety grounding, and switching are key concepts developed into the field. Conduit and well as direct bury cables with an array of fault types are present. Medium voltage cables of various types as well as secondary cables are utilized. This cable complex provides the training environment to allow technicians to use an array of cable test equipment and employ all current industry fault locating and tracing methods with confidence.
- Cable Testing and Diagnostics---Critical to the industry is the need for technicians to be trained in a “real world” environment using the high-tech test equipment now available to perform diagnostic testing of medium voltage cables. The AVO Training Institute via AVO Cable University offers current technologies for testing along with a cable field designed to “stretch” the capabilities and imagination of cable technicians. Cable Diagnosis is critical and AVO offers a comprehensive program ensuring technicians not only know how to perform the tests but also how to interpret the results.
6 Cable Technician Certification
Industry trends require test companies and technicians to provide some level of proof that they have the training and experience in the technical area they are providing the skill. Certification is a method of not only providing the documentation but more importantly ensuring that the technician has demonstrated his proficiency in the technology required. The AVO Training Institute offers its Cable Technician Certification through successful completion of AVO Cable University curriculum. This offering is consistent with the current industry need to provide technicians with the capabilities to “future poof” existing and future medium voltage cable installations.