Английский язык для судовых электромехаников - [38]

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

Selector module. It is used for the selection of the engine room status, attended or unattended, and an engineer on duty. The module is equipped with one circuit board per engineer, and switches and indicating lamps in the front. The unit also provides call of the engineers.

Central unit. Systems with alarm print-out or data logging include the central unit. The control unit is connected to the system via the system bus.

Such systems are programmable bus-oriented electronic systems comprising a number of standard units. The functions in the system are controlled from a central processing unit based on a microcomputer. The functions are determined by a program — the system software — stored on a PROM semi-conductor memory. In addition to the basic functions of the central unit the use of the microcomputer and software make such alarm systems easily expandable to more complex functions.

Typical optional functions available are: presentation of process data on a display, telex transmission of measured values, trend analyses, condition monitoring of the machinery.

The central unit is fitted in a cubicle. The front of the cubicle includes the printer for alarm print-out.

35 . 20

Home exercise. Check vour reading skills. See ex. 32, Section 1, Unit 2.