Т.Ю.Кущ, М.С.ВоловникАнглийский язык для судовых электромехаников. ENGLISH FOR MARINE ELECTRICAL ENGINEERS. 1986

The single convertor can operate in the first and fourth quadrants. The direction of torque can only be changed by reversing the field current of the machine.

Double convertors. In a double convertor there are two sets of thyristors connected in antiparallel (see Fig. 6,b). Both current and voltage can change sign, and the machine can be braked and reversed without additional equipment; this is known as four-quadrant drive.

23 4

- What is wrong with the computer?

As you know, electronic computers can solve intricate mathematical problems, answer complicated questions, translate articles into a foreign language and what not!

One day Field Marshal Montgomery was given a computer. That unexpected help from the War Office greatly pleased him. It took him about 10 minutes to set the problem. It went something like this: — “The enemy has just opened fire from the South. 12 German tanks have just been sighted on top of the hill in front of our lines.. . Two German planes have been shot down...” And finally came the question: — “Should I attack or withdraw?”

At last came the answer: “Yes”. — “Yes, what?!”

Half an hour later came the next answer: — “Yes, Sir”.

24 7

Listen carefully to the recorded texts. Choose a suitable title for each of them. Give reasons for your choice. Speak on some of the details of automatic control that you know and that are provided by the texts.

An automatic control system is defined as one “in which the value of a controlled condition is compared with a desired value and corrective motion is taken dependent on the deviation, without the inclusion of a human element in the closed loop formed by the comparing and correcting chains of elements”.

An automation control system thus includes: the plant, the detecting or sensing element, the measuring or indicating element, the controller.

Automatic control is now recognized by all industrial organizations as being an essential aid to efficient plant operation. The widespread use of automation control in these industries provides the most convincing proof that it is profitable investment.

The advantages from the application of automatic controls in ships are: a) improved conditions for the seagoing staff by transferring much of the “donkey work” from manual operation to automatic operation;

b) savings due to more efficient use of seagoing staff by transfer from watchkeeping to day work; c) saving in maintenance costs.

31

f) Заказ № 8f>!

The fourth class period 25

Listen to paragraphs 1—4, read sentence by sentence and translate them orally in pauses.

26 8

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

1. What are the electronic and alarm measuring systems designed for?

2. What are in your opinion advantages of the electronic alarm system?

3. How can you tell when there is the occurrence of abnormal conditions?

4. What is the design of the standard modules?

27 6

Dwell on the alarm measuring systems with your fellow-student.

28 1

Fill in the blanks with suitable words.

1. The signals from analog and digital . . . are processed in the system.

2. If necessary, the system . . . can easily be modified by the customer.

3. The electronic and alarm measuring systems are designed for centralized ... of processes on board ship.

29 3

Using the notes below speak on the advantages оГ the electronic alarm system.

1. all, transducer, signal, to process, individual, one, circuit board, measure, alarm, channel. 2. one, channel, fail, rest, system, remain, uneffected. 3. necessary, system, layout, easy, modify, customer, move, transducer, connection, correspond, circuit board, transparent, legend plate, to need, take, program, consideration. 4. channel, equip, separate, lamp, alarm, indication, mimic, analog, instrument, presentation, to measure, value.

30 4

Complete the following sentences according to the text.

1. The electronic and alarm measuring systems arc designed to meet...

2. The signals from analog and digital transducers arc processed in the

system and allow for. . . 3. The design of the aiarm systems comprises a limited number of standard modules, and offers. . . 4. All transducer

signals are individually processed, i. e. . . .

31 5

Give the exact translation to the following definitions and explanations.

Component of automatic systems is the simplest and functionally selfdependent structural item used in automatic systems (e.g. relay, resistor, logic element, sensor, final control element).

Environmental strain is environmental factor which is assumed to have deteriorating influence upon the equipment.

Indicating system is the system intended to indicate values of given physical quantities and significant states.

Monitoring system is the general term for alarm, safety and indicating systems.

Reliability is probability of satisfactory functioning in a given period and under predetermined conditions,

Dwell on the above definitions of automatic systems with your fellow-student.

10

33

Read the text. Write a summary in English. Dwell on the nuclear ships with your fellow-students.

Safe Operation of Nuclear Ships

Ice-breakers and ice-classed transport ships are very important in the Soviet merchant fleet due to the geographical position of the USSR. Over the past 20 years, in the Western Arctic sector alone, the volume of shipping has increased eleven-fold, and the navigation season from 90 to 330 days. This results in the first place from a 2.7-fold increase in the ice-breaker fleet power and a 3.7-fold increase of its utilization factor. Why nuclear?

Many years of experience show that for ice-breakers decisive factors are power and endurance. To achieve both, nuclear power plants were indicated.

The Soviet nuclear ice-breakers have, in fact, an unlimited range and endurance of 500 to 700 days. The endurance of conventional icebreakers does not exceed 50 days.

The operational life of Soviet atomic ice-breakers and thus nuclear reactors falls in two stages: the early “Lenin”, built with an experimental nuclear steam-generating plant of the first generation; and the others of the later “Lenin", “Arktika” and “Sibir" with nuclear plants of the second generation.

34 40

Home exercise. Read the text, point out in English in written form what main themes are dwelt upon. Be prepared to dwell on the themes with your fellow-student.

Modules of Alarm Measuring- System

Alarm and measuring modules. They are designed with space for several analog or on/off channel boards. In front of each channel is a transparent legend plate on which the name of the channel is engraved, and a push-button for visual alarm acknowledgement and manual measuring.

The channel boards, which can be located in these modules according to the customer's requirements, are:

1. On/off alarm board, for adapting the on/off transducer signals.

2. Analog channel board, for adapting the analog transducer signal.

3. Average board, for calculation of mean values.

4. Group alarm board, for generation of group alarm signals.

5. Blocking board, for adapting the blocking transducer signals of internal blocking signals.

Display module. It is designated for presentation of analog values on a digital display. Two switches are mounted in the front, and these can be used to determine whether the measured value or one of the set limits is to be displayed when measuring.

Apart from the electronics for interfacing the display, the module includes circuits for generating start signals to the sirens and the rotating lights. The front is equipped with a push button for audible alarm acknowledgement