Английский язык для судовых электромехаников (Кущ, Воловник) - страница 84

Say some words about thyristor convertors.

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Translate at sight.

Convertor module is used in all systems. It is also available as a non-enclosed function module for the current range 40—1400 A.

The convertor module is a complete unit which has been tested for correct operation. It is made up of thyristor unit and convertor control

Fig 7. Converlor module

equipment. The convertor control equipment, in other words the electronic control circuits, consists of circuit boards mounted on a hinged panel. On convertor module 40—400 A the panel is supplied fixed in position; for the 650—1400 A module it is supplied separately.

The convertor control equipment is located on the inside of the panel. The permanent basic functions are grouped on one circuit board, known as the mother board. A number of optional functions in the form of small circuit boards can be connected to this mother board.

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Home exercise. Write the exact translation of the second part of the text above. Be prepared to dwell on convertor module using Pig. 7.

Part II

Mounted on the outside of the. hinged panel is drive control cquip-

merit. The sub-functions are in the form of circuit boards connected to a mother board which provides all the internal connections between the sub-functions. Drive control equipment communicates with the convertor control equipment via a flat cable.

A convertor module can be fitted with all the options available for the convertor control equipment and the drive control equipment.

N. B. The open-core transformer for earth fault protection is supplied as a separate unit.

For supply voltages up to and including 500 V, the primary voltage of the auxiliary supply transformer is the same as the supply voltage of the convertor module. Where the supply voltage is higher, the transformer must be supplied separately with 500 V 60 Hz or 460 V 60 Hz.

For rated currents 230 A and above, an external supply at ПО V 50 Hz or 115 V 60 Hz is required to power and operate a cooling fan.

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Home exercise. Read the text and then write a summary in English. Speak on some of the details of an electronic system operation that you know and that are provided bv the text. Use Fig. 8.

Fig. 8. Simplified block diagram

Programmable signal processing with the electronic system means that the executive functions of a process control system, e. g., is initiated and controlled by a program stored in a memory. On the basis of measured data collected from the process, the system performs the action laid down in the program. The function is therefore not tied to the electrical wiring of the system; it can be adapted to changed operating conditions simply by changing the program.