Both static and dynamic voltage drop can be compensated by using both compensation inputs at the same time.
The unit is used for voltage control, where it replaces the tacho generator of the machine. The output signal is used as the actual value for the speed control system.
The unit is also used together with a field supply for controlled field current, in order to obtain automatic field weakening. The unit is connected at the factory for automatic field weakening if a controlled field exciter is ordered: if not, it is connected for voltage control.
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41
Looking through the text draw a flow chart.
Function Description of Automatic Control System of Electrical Power Plants
Part I. Shutting Down
In order to avoid running the sets at excessively low loads, the set which is next in sequence will be shut down when the load has fallen to a value below a predetermined level,
The shutting down instruction can be initiated by the stop push button being depressed, by a critical or поп-critical alarm being initiated, or for diesels by excessive alternator capacity being available. The ordinary shutting down program implies that the set is first unloaded. When the load has fallen below about 10%. the circuit breaker is tripped and the engine is allowed to run for one minute for the temperature to equalize before the stop solenoid is energized for the period normally necessary for the engine to run down. Starting and stopping instructions interrupt each other, except when the stop instruction is caused by an alarm, the stop instruction then having priority.
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Horne exercise. From sentences below pick up those with Attributive Participle constructions and translate them.
1. The first metals used by primitive people were gold, silver and copper as they were found free in nature. 2. Of all the new materials developed by modern technology radioactive isotopes are among the most useful. 3. The Periodic Law stated by Mendeleyev is of great importance for science. 4. A number of new plastics will be developed in the nearest future. 5. Soviet scientists developed electronic computers to control production technology. 6. The developed technology helps to improve the quality of articles produced. 7. This material becomes soft when heated. 8. The voltage changes according to the curve demonstrated. 9. When compressed a gas changes its volume. 10. Each proton is charged positively. The experiment described attracted great attention. 12. The worker repaired the device used. 13. When repaired the automobile moved at high speed. 14. One of the important devices used in the computers is the magnetic core. 15. This energy is greater than that possessed by the original signal. 16. The laboratory was well ventilated. 17. Distilled water used in the laboratory is a colourless and tasteless liquid. 18. The current flowing in a conductor is measured in amperes. 19. We used all the methods recommended. 20. The new instrument being developed in this plant will be tested in two weeks.