Cast Resin Transformers

In view of the requirement of Indian Industry, we have introduced VOLTAMP Cast Resin (Dry Type) Transformers. This introduction supplements our existing product viz. Vacuum Resin Impregnated Dry Type Transformers. Dry Type Transformers of both the above varieties are in use.

The Company has Resin Impregnated Dry type Transformers up to 5 MVA, 11 KV Class (In Technical collaboration with a leading GERMAN Company) and Cast Resin Dry type Transformers up to 12.5 MVA, 33 KV Class (In Technical collaboration with a leading GERMAN Company).

To offer time proven designs substantiated by reliable field experience, we have entered into Technical Collaboration with M/s. HTT, Hann Munden, GERMANY.

In view of the requirement of Indian Industry, we have introduced VOLTAMP Cast Resin (Dry Type) Transformers. This introduction will supplement our existing product viz. Vacuum Resin Impregnated Dry Type Transformers. Dry Type Transformers of both the above varieties are in use in the Indian Industry. To offer time proven designs substantiated by reliable field experience we have entered into Technical Collaboration with M/s. HTT, Hann Munden, Germany.

M/S. HTT are pioneers in the field of Cast Resin Transformers manufacturing. They have been manufacturing Cast Resin Transformers since 1959. Their range extends up to 16 MVA /36 KV. More than 30,000, HTT Cast Resin Transformers are satisfactorily working in the field comprising of wide range of applications. Repeat orders from several customers reflect the confidence put by them in HTT.

They manufacture Cast resin Power and Distribution Transformers, Converter Transformers, Transformers with On Load Tap Changers (OLTC), Motor - starting Transformers, Testing Transformers, etc. Their specialty is to make special transformers to meet customers' requirements.

Products

Product Range

Ratings :

Ratings 25 KVA to 12,500 KVA. H.V. Voltages :
3.3, 6.6, 11, 22, 33KV. Voltages lower than 3.3kv on request.

L .V. Voltages :

433 V and around. Voltages up to 11KV on request.

Insulation Class :

F (90°C T`emp. Rise), Others on request.

Applicable Standards :

IS1I171 / IEC 60726

Duty :

Distribution & Power Transformers.
Rectifier/ Thyristor duty.
Induction Furnace Duty.
Lighting, Isolation.
Generator Excitation.

Advantage of Cast Resin Transformers

No Fire Hazard.
Near Load Center or even near to load.
Low as transformer is near to load. Also cable drop is reduced.
Negligible smoke generation.
Suitable for indoor use as no fire risk.
Can be fitted outdoor in IP 45 enclosure.
Suitable for as low as -25° C ambient temperature.

Manufacturing Process

Manufacturing Process Core

Three limb core construction is 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. Fibre -glass tape banding hold the core tight and reduce the noise level. Treatment given to the completed core, protects it from atmospheric corrosion.

Windings

Both the H.V. and L.V. windings are made from copper conductors. Round wire, rectangular strip or foil is used depending on current to be carried. Layer type or cross over type winding is used depending on current / voltage to be handled. Windings are cast under vacuum. This is carried out in our state of the art, Automatic Casting Plant manufactured by world leaders M/s. Heidrich, Germany.

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

Protection against Overload/high winding temperature can be provided by Thermistors. ALARM and TRIP are provided, when required, by means of Thermistor or RTD sensors can be provided with 2 set points.