Class F resin encapsulated dry transformers

Nacional de Transformers - TESLA puts at your disposal the local design and manufacture of three-phase transformers encapsulated in epoxy resin with powers up to 5 MVA at voltage levels up to 36 kV according to NTC, RETIE and IEC-EN standards.

Low voltage coils are manufactured on automatic power winding machines, the conductive materials generally used are tape (foil) or rectangular plate, their insulations are of the class F ( 155 ° C ) pre-impregnated type. These coils are cured and dried using the vacuum process.

The medium and high voltage coils are manufactured using automatic winding machines that wrap wire or tape ( foil) in copper or aluminum material with class F insulation ( 155ºC ), the epoxy resin is prepared in vacuum mixing tanks under special conditions of pressure and temperature; the encapsulation process is carried out in an autoclave under the same vacuum conditions, the polymerization and curing cycle is carried out in drying ovens at different temperature ramps.

With the encapsulation system, the characteristics and environmental requirements according to classes E2 , C2 and F1 can be guaranteed.

The magnetic core is made of grain-oriented magnetic steel with high magnetic permeability and low losses. Each sheet of magnetic steel is insulated by a thin layer of organic material (Carlite), the cut is 45 degrees and its columns are stacked using the Step Lap method, reducing hysteresis losses and vacuum currents, guaranteeing a low level. noise.

They are designed with a winding temperature rise of 100 ° C or less, cooled by natural or forced air, winding material: copper / copper , copper / aluminum , aluminum / aluminum , K-factor designs for harmonic control. ( K1 , K2 , K4 , K6 , K9 , K13 , K20 , K30 ), savers in the core and in the windings; also for indoor use with protection cell ( IP 20 , IP 40 ), or for outdoor use with protection cell

NEMA 4 and IP 55 .

On request, a temperature monitor with thermocouples type PT 100 and a connection box for thermal protection of the transformer is supplied. They are delivered or installed SPD for protection against overvoltages and forced ventilation system for power increase of up to 30% of the nominal value; There are also bimetallic connectors for the connection of the TESLA copper-aluminum connection or vice versa.

Transformers suitable to meet the electrical energy requirements in sectors such as: