An ISO 9001 : 2000 Certified Company
OTHER FEATURES :
i). Insulation - Class A Oil impregnated paper insulation with grading type design. This design results in uniform distribution of stress giving excellent transient stability and low levels of partial discharge.
ii). Processing & Oil Filling - CTs are dried and oil filled under very high vacuum (0.05 torr), after going through rigorous process cycles at high temperatures and vacuum (105 deg. C to 120 deg. C and 0.05 torr).
iii). Ratio Changing - Different ratios can be selected with reconnections on primary or secondary sides.
iv). Hermetic Sealing - The CTs are hermetically sealed using Stainless Steel Bellows OR Nitrogen Cushion which effectively prevents the contamination of Transformer Oil with atmosphere, during its service life.
The CTs are of Dead Tank type with main weight of cores and insulation at bottom giving very good mechanical stability considering the extra height of the equipment. INSULATORS used are Hollow types with ALTERNATE SHED Design as per latest IEC recommendation. They are most suitable for HOT LINE WASHING. The design is indigenous based on 25 years of experience in EHV technology and its implementation in extreme climatic conditions of India, right from the hilly region of North & NE to down South & SW Sea Level. All metal parts exposed to atmosphere are either hot dip galvanized or epoxy painted. The primary windings are wound with EC grade copper tubes or copper strips covered with fiberglass insulation. The primary winding is adequately reinforced to withstand repeated mechanical forces developed during the passage of very high short circuiting currents through the CT, due to various faults developed in the system.
Secondary cores are wound with super enameled hermetic grade or PVA based EC copper rounds. The inter - layer insulation is adequately reinforced to withstand the operating voltages as well as transient over-voltages.
All CTs are tested for routine test as per relevant standards. Type tests are frequently carried out to keep the quality check. Facilities for type tests such as temperature Rise and High Voltage Power Frequency Tests (both Wet & Dry), are available in our Lab.
PACKING & TRANSPORTATION :
The CTs are packed in Wooden Crates suitably so that they can be transported Vertically.