Dry type distribution transformers

Technical features

DRY TYPE MEDIUM VOLTAGE TRANSFORMERS CLASSE H

The transformers are built in accordance with IEC 60076-11 standards.
For European market ,the calculation is made according to Ecodesign regulation, norms EN 50588-1.

Manufacture: The core is built up of cold rollered oriented grain steel sheet with low specific losses, insulated on both sides by a thin inorganic coating (Carlyte). The sheets composing the core are cut at 45 degrees. Uniform pressing, stiffnes and solidity of the columns assure a low noise level. The low voltage winddings are made of eletrolitic copper plate. This technology assures an excellent resistance to electrodinamic stresses much higher than the one obtained with traditional elix windings. The insulation between turns is obtained by using class H material. The high voltage windings are realized layers, subcoils or disc, depending on the voltage and the power of the transformer. The conductor is NOMEX insulated or class H enamelled. Adeguate axial channels between the layers of windings grant a uniform cooling. Insulation between high and low voltage and core is made by fiberglass. All the windig are dryed in an oven and impregnated under vacuum by using class H insulating varnishes.

Standard accessories

• Skid under base or truck with bidirectional wheels;
• Lifting lungs;
• Earthering terminal.

Optional accessories

• Thermometer dial type with electric contacts;
• Temperature monitoring unit;

Tests: All the transformers are singly tested with routine test, according to standard IEC 60076-11.
Upon request the following type test can be carried out:
- temperature rise test;
- full wave impulse test.
Special test: short circuit test.

DRY TYPE MEDIUM AND LOW VOLTAGE TRANSFORMERS CLASSE F

The transformers are built in accordance with IEC 60076-11 standards.

Applications: Normal use for transforming voltage up or down and for applications which require a partition between primary and secondary voltage. Protects installations and equipment by generating a new system in which any earth faults are eliminated.

Manufacture: The core is built up of cold roller oriented grain steel sheet; the windings are made of conductor in wire or bars, electrolitic copper or alluminium. Insulating components are made of fiberglass or polyester material. The final treatment is an impregnation under vacuum and drying process.
Construction open type protection IP 00 - Thermal insulation class F - Cooling: natural AN - Voltages: from 50 to 1000 V - Frequency: 50 or 60 Hz - Connection: Star/star+n (Yyn0) or Delta/star+n (Dyn11)

Standard accessories

• Skid under base or truck with wheels;
• Lifting lugs;
• Earthing terminal.

Optional accessories

• Thermal resistance PT100;
• Temperature monitoring unit.

Tests: All transformers are singly tested with routine test, according to standard EC 60076-11.