CIRCUITS AND COMPONENTS PROFESSIONAL ENGLISH IN USE FOR ENGINEERING

 

PROFESSIONAL ENGLISH IN USE FOR ENGINEERING UNIT 45. CIRCUITS AND COMPONENTS

 

A Simple circuits The circuit diagrams below show lamps connected in a parallel circuit and in a series circuit. The supply has live and neutral conductors. On an alternating current (AC) supply, the difference between live and neutral is that conductors on the neutral side of appliances are earthed – that is, connected to earth (the ground. B Mains AC circuits and switchboards Where an AC supply enters a building, it is connected to a switchboard. This has a number of switches to allow different circuits in the building to be switched on and off. Circuits include power circuits. These supply the power sockets (or sockets) for the plugs on appliances. Usually, a circuit C Printed and integrated circuits The circuits in electrical appliances are often printed circuits, on printed circuits boards (PCBs). These are populated with (fitted with) electrical components. Many appliances also contain small, complex integrated circuits – often called microchips (or chips) – made from silicon wafers (very thin pieces of silicon). They act as semiconductors, which can be positively charged at certain points on their surface and negatively charged at other points. This principle is used to make very small circuits. D Electrical and electronic components There are many types of electrical and electronic components. These can be used individually or combined with other components to perform different tasks. For example: ·       Sensors or detectors can sense or detect levels of – or changes in – calues such as temperature, pressure and light.   APPENDIX XII ELECTRICAL AND ELECTRONIC COMPONENTS Common components and their functions Components and symbols   Logic gates Logic gates are electronic devices generally made from transistors and diodes. All types of logic gate, except NOT gates (see below), have two input terminals. The input terminals receive signals in the form of voltages, and are designed to simply detect whether there is a voltage (considered to be signal ‘I’), or not (considered to be the signal ‘0’)   APPENDIX XIII SENSING, MEASURING AND REGULATING DEVICES EXERCISES 45.1 Make word combinations with circuit using words from A and B opposite. Then match the combinations with the descriptions (1-6) below. 1. a circuit containing one or more sockets 2. a simple circuit where all the components are placed one after the other along the same conductor. 3. a microchip – a very small, often complex circuit 45.2 Complete the task from  an engineering textbook. Sometimes more than one word is possible. Look at B and C opposite and Appendix XIII to help you. In an experiment, the lights in a room are connected to two types of electronic (1)____________. The first is an occupancy sensor, which will (2)____________ the movement of a person entering the room, and the second is some kind of photosensor, which can determine whether it’s daylight or dark. 45.3 Can you answer the question in the text 45.2? look at Appendix XIII to help you.

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