Transmission cables can provide 40 or more years reliable service, if operated within allowable temperatures and if properly maintained.  Many utilities operate cable circuits that were installed decades ago, and the utility no longer has personnel familiar with the installation, operation, and maintenance of these cables.  Frequently,  O&M procedures have not been properly documented, and present utility operators do not have clear direction for the type and extent of required maintenance.

O&M Manuals: O&M manuals provide guideance to engineering staff, as well as operators, to know how to insure an available, reliable system.  PDC engineers average more than 30 years experience in cable system O&M, and are pleased to share their experience through field work, manual preparation, and training.

Failure Mitigation: Cable electrical failures and hydraulic problems in HPFF and SCFF cables can take a long time to resolve.  PDC has experience that we incorporate into O&M documents to assist the owner with resolving failures on cable systems, minimizing outage time and improving long-term reliability.

Diagnostic Services: PDC has done extensive laboratory and field testing of cable systems, in addition to participating in state-of-the-art diagnostic equipment development and testing.  Many types of diagnostic services can help identify potential problems before they happen, providing for improved system availability.

Fault Location: Although infrequent on transmission cables systems, failures occur, and distribution cable failures are a daily event at many utilities.  PDC engineers have performed fault location on all system types and participated in the development of a reference manual for the Electric Power Research Institute to help in fault location diagnostics.  This topic is critical to include in O&M procedures.

PDC services include:

• SYSTEM CHARACTERIZATION - Perform an audit of the utility's system from manhole floor to termination connections and then prepare procedures suitable for the system.

• OPERATION & MAINTENANCE MANUAL - Generally, a custom manual is prepared for each transmission cable circuit and provides comprehensive guidance for the circuit.    PDC will work to develop a suitable manual, either in conjunction with a new circuit or for existing circuits that need to be characterized.  Topics to consider:

• Allowable loading:  steady-state, contingency
• Pipe / duct inspection and maintenance, including corrosion coating
• Cathodic protection systems; grounding
• Fluid handling plants; standby generators
• Terminal and splice inspection
• Fluid sampling and analysis
• Manhole and other structure inspection
• Surge protection
• Fluid leak detection, location, repair
• Electrical failure detection, location, repair
• Spare parts requirements
• Fluid freezing
• Resources for materials and repair services

• TRAINING - Although the O&M manual will be complete and freestanding, utilities still find that formal training by knowledgeable engineers will be invaluable in instructing field personnel - and engineers - in proper O&M procedures.  PDC has conducted many such seminars.  Length is one or two days, depending upon the amount of background information, system complexity, utility experience, etc.  This training is especially useful if other departments such as substation operators or line crews, will be responsible for O&M and trouble calls on the cable.  Some utilities videotape the courses, for later viewing by other personnel.

• FIELD SERVICES -  PDC has qualified engineers and technicians who can provide scheduled or emergency field services for inspection, failure analysis, supervision, and testing.