The core is constructed from low loss, cold rolled, grain oriented, annealed laminations of electrical sheet steel conforming to the latest international standards. Special frame is built in-house for clamping the core to reduce the magnetic noise as well as making the whole structure rigid & robust.
Coils are wound with electrolytic high conductivity paper covered or synthetic enameled copper conductors. Cooling ducts are provided to keep the hot spot temperature as low as possible. Coils are dried in electric ovens. Rigid connection support and coil clamping is provided to ensure high short circuit strength.
Pre-compressed board PARMALI board and JAPANEESE insulation paper of best quality is used.
Oil is tested for resistivity, dielectric and acidic characteristic conforming to IS-335. Before topping up oil is filtered thoroughly.
The tanks are made of MS steel plates/sheets with adequate bracing & stiffness. Tanks are pressure tested to withstand any type of inside or outside pressure. All the external surfaces are given a primary coat of zinc chromate, red oxide and two finishing coats of grey paint. The inner surfaces are given a coat of heat and oil resisting paint.