In view of the requirement of Indian Industry, we have already introduced IEC Cast Resin (Dry Type) Transformers. This introduction will supplement our existing products. Dry Type Transformers of both the varieties (Cast Resin type and Vacuum Impregnated Type) are in use in the Indian Industry. IEC manufacturers only Cast Resin Type Transformers as per the IS- IS 11171 / IEC 60726
Ratings 25 KVA to 1,500 KVA.
H.V. Voltages: 11, 22, 33KV. Voltages lower than 11KV on request
433 V and around.
F (90°C Tempe. Rise)
IS 11171 / IEC 60726
Advantage of Cast Resin Transformers
No Fire Hazard
Near Load Center or even near to load
Low Cable Losses as transformer is near to load.
Negligible smoke generation
Suitable for indoor use as no fire risk
Can be installed outdoor in IP 45 enclosure.
Suitable for as low as -25° C ambient temperature
Manufacturing Core Process:
Three limb core constructions are used. Core sheets conforming to drawings are made from Cold Rolled Grain Oriented (CRGO) Silicon Steel sheets. Individual sheets come duly coated with inorganic insulation. Circular Core cross section is used which is obtained by assembling number of steps of different widths. Number of steps and step widths are optimized to gain maximum advantage. Mitred joints are used between the limb plates & yoke plates. Fiber -glass tape banding hold the core tight and reduce the noise level. Treatment given to the completed core protects it from atmospheric corrosion.
Winding And Protection
Both the H.V. and L.V. windings are made from copper conductors. Round wire, rectangular strip is used depending on current to be carried. Layer type or cross over type winding is used depending on current / voltage to be handled.
On the H.V. side, inserts are provided to receive tap changing links. Inter connections between H.V. phases are obtained by links made out of copper tubes with their ends formed into lugs. These links are insulated by means of heat shrinkable tubes.
Protection against Overload/high winding temperature can be provided by Thermistors. ALAAM and TRIP are provided, when required, by means of Thermistors or RTD sensors can be provided with 2 set points.
Rating & diagram plate
Skid under base or truck with bidirectional wheels
Secondary terminal lifting lugs
Enclosure with IP 21,23 or other protection class
Temperature monitoring unit with display
Over current relay
Forced ventilation system
All routine tests list below are carried out at our factory during final testing according to standard IEC 726/ IS 2026 / IS 11171.
Insulation Resistance Test
Winding Resistance Test
Turns Ratio Test
No load Current Test
No load losses Test
Full load losses Measurement Test
Impedance Voltage of Transformer
High Voltage Test
Temperature Rise Test
Induced Voltage Test
Insulation level & Dielectric Test
Polarity Phase Relationship Test
Break down value test of Transformer Oil
Short Circuit withstand Test
Upon request the following type test can be carried out on customer's request