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POWER CABLE AS USED IN UNDERGROUND DISTRIBUTION SYSTEM

POWER CABLE AS USED IN UNDERGROUND DISTRIBUTION SYSTEM How are conductor and materials for power cables being specified? Conductor material and insulation type will be specified. Restricting extensions of existing systems to a specific conductor material and insulation type in order to match an existing cable type is permitted only when a need has been established. Neutral cables, where required, will be installed with 600V  insulation unless concentric neutral cable is used. In duct lines, neutrals will be installed in the same conduit with associated phase cables. Conductor material. Since underground conductors are continuously supported, soft-drawn copper or aluminum alloy 5005 provides adequate strength. However, the selection of copper or aluminum will be justified based upon an analysis using life, environmental, and cost factors. The need for mechanical flexibility requires that conducts be stranded, and the NEC makes this mandatory for cables larger than No. 8 AWG instal...

UNDERGROUND DISTRIBUTION LINES USING POWER CABLE IN AN ELECTRIC DISTRIBUTION SYSTEM

UNDERGROUND DISTRIBUTION LINES USING POWER CABLE IN AN ELECTRIC DISTRIBUTION SYSTEM How are power cables being used in an electrical distribution system? Underground distribution lines have been a long known technology used by many electric utilities in delivering power to its customers. This set up can usually be found in highly urbanized areas where space for overhead lines can be scarce. Various pros and cons are known to be associated in using underground distribution lines in a power distribution system. Like any other construction which involves public or private area, distribution system using underground lines installation must at all times coordinate with the installation master plan of the city or with any private properties to avoid conflict with construction of future facilities. For easy access for inspection and maintenance, underground lines are normally installed adjacent to roadways in urban, housing, or industrial plant areas, but may be routed as required to meet ...

WAYS AND MEASURES IN PROTECTING DISTRIBUTION LINE CONDUCTORS FROM DAMAGES

WAYS AND MEASURES IN PROTECTING DISTRIBUTION LINE CONDUCTORS FROM DAMAGES  What are the ways in protecting line from damages that occur in transmission and distribution lines? Gentle Handling of Cable - Careful handling in the field to avoid scratches, cuts or kinks in the conductor is desirable during the field operations of paying out, stringing, and tying or clipping in. Follow Sag-Tension Charts - Sagging conductors at tensions higher than recommended increases susceptibility to aeolian vibration. Sagging in at tensions lower than recommended reduces the probability of aeolian vibration but increases susceptibility to galloping. The Use of Armor Rods on Conductors - Armor Rods are intended for clamp supports, but they can also be used at tied supports. Armor rods are effective in sacrificing their surface to abrasion instead of the conductor’s outside surface. In addition, they provide protection against electrical burning of the conductor from flashovers. Armor rods d...

COMMON LINE DAMAGE IN A DISTRIBUTION SYSTEM FEEDER LINE

COMMON LINE DAMAGE IN A DISTRIBUTION SYSTEM FEEDER LINE   What are the common of line damages that occur in transmission and distribution lines?  The cause of damages to transmission and distribution lines can be attributed to many potential reasons. Conductors are one of the most exposed electric company asset to many unfortunate events. The cost of conductors is one of the major expenses in any overhead power line construction. It is the primary component in the flow of revenue for a utility and the component most exposed to hazards. With the introduction of aluminum conductor, the vulnerability to damage increased due to its easily abraded surface. The four types of motion occurring on overhead power lines are (1) aeolian vibration, (2) galloping, (3) sway oscillation and (4) unbalanced loading. Each is independent in cause and effect. Insulator and conductor damage can be classified into four main points; where lines are seldom inspected, the first indication of damage ...

CIRCUIT PROTECTION FOR DISTRIBUTION SYSTEM FEEDER LINE

CIRCUIT PROTECTION FOR DISTRIBUTION SYSTEM FEEDER LINE How an electric utility protects its distribution system line? An electric utility’s role in an electric power system does not only focus on the delivery of power to its customers. They also need to concentrate in the conservation of their assets in the network. Assets in the system like the transformers, wires, structures, etc., have an equivalent monetary value where the utility must always take care of. The ability of the electric distributor to minimize the damage during failure at the fastest time possible is very important since this means property loss can also be in the minimum. Relaying fundamentals is an important tool that protection engineers must possess in order to carefully analyse their own system. The most common form of distribution system feeder line protection which is also the most important is the overcurrent protection. Its basic application is mostly on substation protection and distribution feeder line p...

DISTRIBUTION SYSTEM MODELING AND ANALYSIS BOOK

DISTRIBUTION SYSTEM MODELING AND ANALYSIS BOOK By William H. Kersting This is the first book dedicated to distribution systems that is truly modern, covers computer applications, and gives a thorough grounding in modeling and analysis techniques. Assuming a basic foundation in transformers, electric machines, transmission lines, and symmetrical components, it serves as both a text for upper-level electrical engineering studies and as an essential reference for practicing engineers. CHECK OUT THIS BOOK

SPATIAL ELECTRIC LOAD FORECASTING BOOK

SPATIAL ELECTRIC LOAD FORECASTING BOOK By H.Lee Willis Containing 12 new chapters, this second edition offers increased coverage of weather correction and normalization of forecasts, anticipation of redevelopment, determining the validity of announced developments, and minimizing risk from over- or under-planning. It provides specific examples and detailed explanations of key points to consider for both standard and unusual utility forecasting situations, information on new algorithms and concepts in forecasting, a review of forecasting pitfalls and mistakes, case studies depicting challenging forecast environments, and load models illustrating various types of demand. CHECK OUT THIS BOOK