Английский язык для судовых электромехаников - [49]

26 2

Translate the following:

the city tram, the City Soviet, the system design, the computer programme, the information processing, institute research, the control process, the process control, power plant, load sharing, alarm conditions, classification societies, start blocking, stationary diesel alternator sets, stop instruction, alternator capacity, control panel switch, programmable digital signal processing.

27 4

Listen to paragraphs 2—4, read sentence by sentence and translate them orally in pauses.

28 5

Respond to the questions. Compare your results with the text.

1. What is the purpose of the automatic control equipment?

2. What are the advantages of the system?

3. What main functions of the automatic control system can you name?

29 2

Fill in the blanks with suitable words.

1. Selection of the ... of diesel alternators is a manual operation.

2. At ... a programmed number of sets will be started and the set which is first to reach frequency will be connected to the ... 3. A special unit in the automatic is available for ... of connection of large loads.

30 4

Using the notes below speak on operations which the automatic control equipment must carry out:

1. full, operation, equipment, carry out, starting, synchronizing, load, sharing, several, diesel alternator, power, demand, increase, disconnect, stop, event, excessive, available. 2. event, fault, set, alternator, automatically, start, connect, main, busbar. 3. black-out, program, number, set, start, first, reach, frequency, connect, busbar. 4. special, unit, available, program-blocking, connection, large, allow, equipment, ensure, always, sufficient, power, load.

31 4

Complete the following sentences according to the text. Compare the results with the text.

1. The only manual operations needed are... 2. The automatic control equipment is designed to meet the requirements made by classification societies on equipment in UER. This implies. . . 3. The automatic control equipment can be connected to the general alarm system on board, provided that. . . 4. A special unit in the automatic is available for programblocking of connection of large loads, thus allowing the automatic equipment to. . .

Give Russian equivalents for the following sentences. Pay attention to the underlined words.

1. We found new routes, the older ones being unsatisfactory. 2. For our purposes we may think of operation principle of the new device as being like one of all the rest. 3. This method is not the one to use. 4. The results were very favourable, especially that of mine. 5. The rates and molecular weights are affected by lowering the temperatures, the former being decreased and the latter increased. 6. Both floating and shore-based storage facilities are needed. The former serve operational needs, while the latter are for long-term storage.

35 3

Read the text, point out the Attributive groups and translate them. Ask each other questions covering the text.

Part III. Synchronizing

As soon as the lower frequency alarm limit has been passed, the synchronizing unit will be switched in and will sense the difference in phase relationship and frequency between the alternator and busbars. On the basis of these parameters, a control signal will be generated and will actuate the speed governor so that the generator will be rapidly brought into synchronism with the busbars. The voltage difference between the alternator and the busbars is detected by a breaker closing unit which will initiate closure of the circuit breaker as soon as the voltage difference tends towards zero at a sufficiently slow rate. If the difference in amplitude is excessively large, closure of the breaker is blocked.

The synchronizing process is supervised so that if it lasts for more than a predetermined period, a synchronizing alarm will be initiated causing the set to be stopped and further starting attempts to be blocked.

36 50

Home exercise. Read the text. Divide it into logical units. Point out in English in written form what main themes are dwelt upon. Then in a few words express the main idea of each passage.

Part IV. Starting Program for Diesel and Turbo Alternators

If the load on the sets in service should exceed a certain percentage of the rated output, a new set must be connected in. That level is normally 80 percent. However, in some systems the levels for starting a new set are detected on the basis of the sum of all the sets then in service, e. g. the total power available. This arrangement allows for better utilization of the sets. In order to avoid starting a new set as a result of the appropriate level being temporarily, e. g. when starting a new consumer with a large starting current demand, the starting instruction is delayed by an adjustable period.

On receipt of automatic starting order, the prelubrication pump will first be started and when its pressure switch delivers a signal to indicate that the oil system is pressurerized, the solenoid of the starting air valve will be energized. The supply of starting air is maintained until the ignition speed has been exceeded or for a predetermined maximum period, normally 5 s. If the engine fails to start, the attempt is repeated, normally twice, at an interval of about 5 s. If all starting attempts have failed, the “starting failure” alarm will be initiated. This alarm will also be initiated if the engine has failed to attain normal speed after a predetermined period, normally 30 s. When the ignition speed has been exceeded preexcitation is initiated by a contact function which persists until the voltage is acknowledged or an alarm is initiated. At this speed a time delay is also initiated for activating certain alarms, e. g. alarms for low voltage, low frequency and low lubricating oil pressure.