1250 KVA 11/.433 KV TRANSFORMERS

Product Range

Power & Distribution Transformers from 25 KVA to 5000 KVA upto 33 KV.

Standard

Rosun power  transformers, are designed and tested as per IS : 2026, BS - 171, IEC - 76 & IEC - 726.

Vector Group

Transformers will be connected as per vector group reference Dyn 11. Other vector groups can be offered as per specific requirements.

Terminal Arrangement

H. V - Bare Bushings or Cable Box, L. V-Bare Bushings or Cable Box. Disconnecting

Temperature Rise

Rosun power  transformers, transformers are designed for a maximum temperature rise of 40/50 degree C of oil/winding. Lower temperature rise can be offered on request.

Core

The core is constructed from low loss, cold rolled, grain oriented, annealled lamination 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 and robust.

Windings

Coils are wound with electrolyte high conductivity paper covered or synthetic enamelled 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 shot circuit strength.

Insulation

Pecompressed board PARMALI Board and JAPANEESE insulation paper of best quality is used.

Tapping

A. OFF CIRCUIT TAP CHANGING SWITCH Tappings from + 5% to - 5% in steps of 2.5% for HV variation or as per customer's requirement.
B. ON LOAD TAP CHANGER 16 steps OLTC for HV variation from + 5% to - 15% in steps of 1.25% or as per specific requirements. OLTC for remote/auto/parallel operation can also be offered.

Oil

Oil is tested for resistively, dielectric and acidic characteristic conforming to IS - 335. Before topping up oil is filtered thoroughly.

Tanks

The tanks are made of M.S. 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.