Give the Russian equivalents of the following sentences.

1. Табличка на трансформаторе содержит всю информацию, требуемую для правильной работы и обслуживания трансформатора.

2. Тепло создаваемое в генераторе, определяется током и напряжением.

3. Электроемкость трансформатора ограничивается позволяемым повышением температуры во время его работы.

4. Наиболее важной информацией является киловатт-ампер режим трансформатора.

5. Другая информация, предоставляемая на табличке, первичное и вторичное напряжение, позволяемое повышение температуры, требование охлаждения, частота.

6. В зависимости от типа трансформатора и его применения могут быть указаны другие показатели (идентификации).

Make up the plan to the text and retell it.см.83 стр.

UNIT 17 (PART 4). TRANSFORMERS

Words to remember.

prevent – предотвращать, не допускать

injury – повреждение

agent – вещество

cooling – охлаждение

submerge – погружать

substitute– заменитель

varnish – лак

sealed dry type – запечатанный сухой тип

Read the text.

Methods of Transformer Cooling

The wasted energy in the form of heat generated in transformers due to unpreventable iron and copper losses must be carried away to prevent excessive rise of temperature and injury to the insulation about the conductors. The cooling method used must be capable of maintaining a sufficiently low average temperature. It must also be capable of preventing an excessive temperature rise in any portion of the transformer, and the formation of “hot spots.” This is accomplished, for example, by submerging the core and coils of the transformer in oil, and allowing free circulation for the oil. Sometimes, for reasons of safety, the use of oil as a cooling agent is prohibited. (Oil can be a fire hazard.) In these situations, special fluids, known as “askarels” can be used in place of oil. However, when using these substitutes, the varnishes which are generally applied to the insulation of the coils must be chosen carefully. For indoor use, in clean, dry locations, open dry-type air cooling can be used. For outdoor or indoor, use, a sealed dry type can be obtained.

Some transformers are cooled by other means: (a) by forced air or air blast, (b) by a combination of forced oil and forced air, and (c) in some special applications, by water cooling.

Put questions to the text.

Speak about.

a) The reason of carrying away the wasted energy in the form of heat generated in transformers.

b) Types of cooling and substances (agents) used for cooling.

UNIT 17 (PART 5). TRANSFORMERS