FLT winding are designed using electrolytic grade, high conductivity copper / aluminum conductors to meet the electrical, mechanical and thermal requirements. Copper / aluminum wire rods are procured from major producers and care is taken to ensure that its conductivity is as per Indian and International standards.
Suitable, strips / wire sizes are drawn out and the conductor is annealed to the required hardness. The insulation paper used for covering the conductors is tested for low ash content, low moisture absorption thus ensuring compliance to Indian and International standards.
All wound coils are pressed, clamped and dried in a circulating in appropriate oven prior to impregnation in oil. This enhances short circuit ability under fault conditions. Inter-turn and inter-layer insulation reinforcements are provided to withstand surges. Adequate horizontal and vertical ducts are provided to ensure that the temperature gradient between the windings and the oil does not exceed the limit and no hot spots develops.