|Windings (reels and cores in contact with them), when insulated with:|
|*material of class A (1)||75|
|*material of class E (1)||90|
|*material of class B (1)||95|
|*material of class F (1)||115|
|*material of class H(1)||140|
|*other materials (2)
exterior cases of fixed transformers (3)
exterior cases, handles and similar parts of mobile transformers (3)
|if these parts are continuously held in hand during normal use:
|If these parts are not held in hand during normal use:
|1) The material classification is in compliance with IEC 85 publication.
2) In case of using materials different from the ones indicated in the IEC 85 publication, under the A, E, B, F and H names, the materials used must comply with the tests mentioned in 13.3.
3) If any element is a part of the transformer external surface, the over-temperature of that element must not exceed the established temperature of its external housing.
4) Table referring to ambient temperature of 25°C.
|POWER TAKEN ACCORDING TO THE AMBIENT TEMPERATURE|
|Obtainable power (%)||100||90||80||72||66||62|
|POWER OBTAINABLE ACCORDING TO ALTITUDE|
|Taken power (%)||100||97,5||95||90||85||80|
|TEST VOLTAGES||Work voltage not exceeding:|
|TEST VOLTAGE APPLICATION POINTS||<50||150||250||440||690||1000|
|a) Between live parts of primary and secondary circuits. (This rule is not applied to circuits separated by an earthed metal shield).||500||2000||3500||4200||5000||5500|
|b) Through the basic or supplementary insulation among:
* the live parts which are or could become of different polarities.
* the live parts under tension and earth, if it (earth) is meant to be connected to the protection conductor.
* the accessible metallic parts and a metal bar with the same diameter as the flexible cable fitted into the input pipes, bushes, anchor devices and similar.
|c) Through a reinforced insulation, between the earth and the live parts under tension.||500||2000||3500||4200||5000||5500|
|1) Test voltage values for intermediate work voltage values can be obtained for the interpolarization of the table values.|