H.T. DISTRIBUTION TRANSFORMS

Maestro make Sealed/Conventional, Single/Three Phase, 50 Hz aluminium/copper double wound, oil immersed, continuous heavy duty transformers are designed with Class A / Class F insulation to withstand short circuit and impulse test standards. These are robust and durable machines which last for many years.

Core used is made from best grade imported cold rolled grain oriented silicon steel laminations with the hi-tech latest technique of annealing. Reduced core losses and magnetizing the current considerably, core is specially designed to sustain over fluxing up to 12.5%. Individual stamping insulated on both side with oil and temperature resistant insulating material. Core is stamped with steel channels rigidly to reduce the sound level and earthed with electrical grade copper sheet.

The winding are of different type 1)Spiral 2)Crossover 3)Helical 4)Disc, designed to withstand the optimum electrical, mechanical, dynamic and thermal stresses depending upon the current and voltage. The coils are wound with electrolytic grade high conductivity, annealed wire and strips covered with high quality insulation. All coils are reinforced, insulated and impregnated with insulating varnish to with stand the effect of short circuits and impulse voltage shocks. Cooling ducts are provided to minimize the hotspot temperature and temperature gradient between winding and oil.

The Insulation material like pre-compressed boards, blocks, corrugated cylinders, Bakelite tubes, insulating tapes, empire sleeves, glass sleeves, varnish, epoxy bushing, porcelain bushing etc. are used of best quality to ensure long life of transformers. Oil used as a coolant and insulating medium is of best quality confirming to IS:335. Before filling in to the transformers, oil is centrifuged, dehydrated and filtered through ’Stream Line Filtration plant’ and tested to ensure free from moisture.

The Tanks are made from prime quality mild steel sheets, plates and pipes by electrical welding. Proper bracing and stiffeners are provided for robust construction. The tanks are tested as specific pressure for leakage at joints. Sufficient cooling radiators are provided for maximum dissipation of heat during extreme ambient temperatures. The radiators are made from best grade presses steel fins or elliptical tubes.

Tank surface exposed to atmosphere is galvanized / painted with two coats of red oxide paint to provide maximum resistance to corrosion and two coats of epoxy based anti-corrosion enamel paint. Surface in contact with oil is treated with two coats of ‘Oil and Heat Resistant paint’. This paint has more effective resistance compared to ordinary enamel paint against corrosion and oil/heat reactions.

Dyn11, Various vector groups can be provided as per requirement.

Designed for maximum temperature rise at full rated load 40⁰C / 50⁰C for oil and winding of aluminium wound transformers and 45⁰C / 50⁰C for oil and winding of copper wound transformers.

Maestro Transformers are designed for overloading more than normal rating as per IS:6600

H. V. - Bare Bushings or Cable Box, L. V. - Bare Bushings or Cable Box. Disconnecting chambers can also be provided on both HV and LV Cable boxes.