Oil Filled Current Transformers From Skipper Voltage Class Up To 220 Kv Construction Type Live Tank Certifications Ce

OIL FILLED CURRENT TRANSFORMERS

SKIPPER manufactures Oil Filled Current Transformers upto 220 kV class. Skipper make Transformers are currently in operation in challenging locations and have been delivering outstanding performance consistently for over 25 years. These transformers comply with international quality & safety standards and environment stipulations.

DESIGN

Oil filled current transformers use current transformation principle to convert highline current (in HV system) to a low current reduced by a fixed ratio. The current transformers are designed generally in live tank construction for optimum performance.

The primary winding is manufactured from copper conductor and is placed in the top housing. The windings are rigid, concentric with uniformly distributed secondary winding to deliver high mechanical strength against short circuit forces.

The secondary windings and the cores are contained in closely fitting rigid shell. The shell is fully insulated from the top housing. The secondary leads are taken to the base passing through a hollow insulator.

Insulation is provided by electrical grade high grade Kraft paper. The fully assembled CTs are dried and oil filled under vacuum in evacuated heating chambers. Optimum insulation and long life is achieved by drying the paper insulation by heat in vacuum. Oil, impregnated under vacuum, complements the insulation.

CONSTRUCTION

Skipper uses brown glazed porcelain insulator with shed profile as per IEC 60815 for the CTs. Optionally grey shade porcelain and other profiles can be offered as per specific requirements. The porcelain insulator is cemented to aluminum alloy flanges on both the sides for maximum mechanical strength. The top housing is of corrosion resistant aluminum alloy to install core coil assembly.

The top of the tank has an oil filling plug. The CT is protected from the vagaries of weather and can withstand extreme temperature variations. Core of wound ring type are manufactured from High quality silicon steel. However, Mu-metal cores are used for select applications. Adequate design, material and process selection ensures that all requirements relating to metering and protection are met.

The secondary winding is uniformly distributed over the circumference of the core to minimize the reactance of the winding. This also ensures accurate transformation ratio. The CT base chamber is fabricated from structural steel. This chamber is provided with secondary terminal box, oil sampling valve and earthling pads.

TESTING

Skipper’s testing laboratories are fully equipped with latest testing equipment and are capable of conducting all routine tests including Partial discharge test.

Skipper oil filled current transformers are tested under stringent conditions for their performance, reliability and durability at NABL accredited labs such as ERDA and CRPI (India). Type tests and special tests are also conducted on all new designs to verify that the product design meets all operational requirements.

QUALITY MANAGEMENT SYSTEM

Our experienced and quality conscious workforce carries out quality control at each stage of production. A series of quality checks are performed on each unit before handing over the same for the next stage. The Quality Assurance department maintains and updates all quality control documents and carries out its own additional inspection at critical hold points. Skipper’s Quality system is in accordance with ISO 9001-2008 and products are CE certified.