Tiếng Anh chuyên ngành Kỹ thuật điện (Phần 2) - Nguyễn Quốc Hùng

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 Unit 6 Electric Motors 
Vocabulary and Pronunciation 
Exercise 1 Match English terms and Vietnamese translations 
English Vietnamese 
1. mechanical energy Cổ góp 
2. armature Cơ năng 
3. reverse polarity cuộn dây kích thích 
4. impedance đảo cực 
5. pulsating force đầu máy xe lửa 
6. traction motor Động cơ kéo 
7. electric railways Động cơ xén cỏ 
8. locomotives Đường xe điện 
9. torque lực mạch động 
10. compact design Mạch tyristo 
11. commutator mô men xoắn, mô men quay 
12. thyristor circuit nửa chu kỳ 
13. half-wave Phần ứng 
14. revolutions per minute (rpm) Ray tiếp xúc 
15. weed trimmer motors số vòng quay trong một giây 
16. field windings thiết kế nhỏ gọn 
17. third rail Trở kháng 
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Exercise 2 T.S 1 Listen and practise 
1. mechanical energy 7. electric railways 13. half-wave 
2. armature 8. locomotives 14. revolutions per 
minute (rpm) 
3. reverse polarity 9. torque 15. weed trimmer motors 
4. impedance 10. compact design 16. field windings 
5. pulsating force 11. commutator 17. third rail 
6. traction motor 12. thyristor circuit 
Exercise 3 T.S 2 Listen and complete the sentences by selecting the correct 
word from the box to fill in the gap 
mechanical energy electric railways half-wave 
armature locomotives revolutions per minute (rpm) 
reverse polarity torque weed trimmer motors 
impedance compact design field windings 
pulsating force commutator third rail 
traction motor thyristor circuit 
1. An inside rotor attached to the output shaft that 
is given a by the rotating 
field. 
2. An electric motor uses electrical energy to 
produce  
3. Universal motors can rotate at relatively 
..(rpm). 
4. a small fan blade attached to the 
acts as an artificial load to 
limit the motor speed to a safe value. 
5. By changing the connected to the rotor circuit, 
the speed/current and speed/torque curves can be altered. 
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reading: Universal motors
Exercise 4 Read the passage carefully and decide whether the statements 
are true (T) or false (F) 
A variant of the wound field DC motor is the universal motor. The name derives 
from the fact that it may use AC or DC supply current, although in practice they 
are nearly always used with AC supplies. The principle is that in a wound field 
DC motor the current in both the field and the armature (and hence the resultant 
magnetic fields) will alternate (reverse polarity) at the same time, and hence the 
mechanical force generated is always in the same direction. In practice, the 
motor must be specially designed to cope with the AC current (impedance must 
be taken into account, as must the pulsating force), and the resultant motor is 
generally less efficient than an equivalent pure DC motor. Operating at normal 
power line frequencies, the maximum output of universal motors is limited and 
motors exceeding one kilowatt are rare. But universal motors also form the basis 
of the traditional railway traction motor in electric railways. In this application, 
to keep their electrical efficiency high, they were operated from very low 
frequency AC supplies, with 25 Hz and 16 2/3 hertz operation being common. 
Because they are universal motors, locomotives using this design were also 
commonly capable of operating from a third rail powered by DC. 
The advantage of the universal motor is that AC supplies may be used on motors 
which have the typical characteristics of DC motors, specifically high starting 
torque and very compact design if high running speeds are used. The negative 
aspect is the maintenance and short life problems caused by the commutator. As 
a result such motors are usually used in AC devices such as food mixers and 
power tools which are used only intermittently. Continuous speed control of a 
universal motor running on AC is very easily accomplished using a thyristor 
circuit, while stepped speed control can be accomplished using multiple taps on 
the field coil. Household blenders that advertise many speeds frequently 
combine a field coil with several taps and a diode that can be inserted in series 
with the motor (causing the motor to run on half-wave rectified AC). 
1. The universal motor can operate in AC only. 
2. Impedence is not important in designing a universal motor. 
3. It is dificult for a universal motor to produce the output of over one 
kilowatt when operating at normal power line frequencies. 
4. The commutator can work for a short time. 
5. A thyristor circuit is a solution to continuous speed control of a universal 
motor running on AC 
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Exercise 5 Choose a correct word to fill in the gap 
useful rotate limit cost 
into permanent due to exceed 
Universal motors can . (1)at relatively high revolutions 
per minute (rpm). This makes them . (2)for appliances 
such as blenders, vacuum cleaners, and hair dryers where high-speed 
operation is desired. Many vacuum cleaner and weed trimmer motors exceed 
10,000 rpm, Dremel and other similar miniature grinders will often 
.(3)30,000 rpm. Motor damage may occur 
. (4)overspeed (rpm in excess of design specifications) if 
the unit is operated with no significant load. On larger motors, sudden loss of 
load is to be avoided, and the possibility of such an occurrence is 
incorporated  (5)the motor's protection and control 
schemes. Often, a small fan blade attached to the armature acts as an artificial 
load to  (6)the motor speed to a safe value, as well as 
provide cooling airflow to the armature and field windings. 
With the very low  (7)of semiconductor rectifiers, 
some applications that would have previously used a universal motor now 
use a pure DC motor, sometimes with a . (8)magnet field. 
Exercise 6 Complete the sentences by finding the missing letters 
1. The energy acquired by the objects upon which work is done is known as 
m.l energy. 
2. In electrical engineering, an a.e is one of the two principal 
electrical components of an electromechanical machine--a motor or generator. 
3. Electrical ie describes a measure of opposition to a 
sinusoidal alternating current (AC). 
4. A t.n motor is a type of electric motor used to power the 
driving wheels of a vehicle such as a railroad locomotive, electrical multi-unit 
train (such as a subway or light rail vehicle train), a tram, or an automobile. 
5. A le is a railway vehicle that provides the motive power for 
a train. 
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6. A te (τ) in physics, also called a moment, is a vector that 
measures the tendency of a force to rotate an object about some axis. 
7. A c.r is an electrical switch that periodically reverses the 
current direction in an electric motor or electrical generator. 
8. R.ns per minute (abbreviated rpm, RPM, r/min, or 
r·min−1) is a unit of frequency: the number of full rotations completed in one 
minute around a fixed axis. 
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 Unit 7 Batteries 
Vocabulary and Pronunciation 
Exercise 1 Match English terms and Vietnamese translations 
English Vietnamese 
Battery pin sơ cấp 
Charge pin địên phân 
charging current có thể nạp lại 
chemical energy pin thứ cấp 
chemical reaction pin nhiên liệu 
Discharge nạp, sạc 
Disposable dòng điện nạp (sạc) 
electrochemical pin, ắc quy 
electrolytic cell phản ứng hóa học 
fuel cell pin vonta 
irreversible reaction dùng một lần 
primary cell phản ứng không thuận nghịch 
Rechargeable hóa năng 
secondary cell xả, phóng điện 
voltaic pile điện hóa 
Exercise 2 T.S 1 Listen and practise 
1. battery 6. discharge 11. irreversible reaction 
2. charge 7. disposable 12. primary cell 
3. charging current 8. electrochemical 13. rechargeable 
4. chemical energy 9. electrolytic cell 14. secondary cell 
5. chemical reaction 10. fuel cell 15. voltaic pile 
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Exercise 3 T.S 2 Listen and complete the sentences by selecting the correct 
word from the box to fill in the gap 
fuel cell secondary cells irreversible reaction 
Charge electrolytic cell primary cell 
charging current electrochemical rechargeable 
1. A  is an electrochemical conversion device. 
2. An  is an reaction which cannot be changed. 
3. . is the current that flows into a capacitor when a voltage is 
first applied. 
4. A rechargeable battery is a group of two or more . . 
5. The anode of an is positive, and the cathode is negative. 
Reading: 
Battery 
In electronics, a battery is two or more electrochemical cells which store 
chemical energy and make it available as electrical energy. Common usage has 
evolved to include a single electrical cell in the definition. There are many types 
of electrochemical cells, including galvanic cells, electrolytic cells, fuel cells, 
flow cells and voltaic piles. A battery's characteristics may vary due to many 
factors including internal chemistry, current drain and temperature. 
One common division of batteries distinguishes two types: primary 
(disposable) and secondary (rechargeable). Primary batteries are designed to be 
used once only because they use up their chemicals in an effectively irreversible 
reaction. Secondary batteries can be recharged because the chemical reactions 
they use are reversible; they are recharged by running a charging current through 
the battery, but in an opposite direction to the discharge current. Secondary, also 
called rechargeable batteries can be charged and discharged many times before 
wearing out. After wearing out some batteries can be recycled. 
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The name "battery" was coined by Benjamin Franklin for an arrangement of 
multiple Leyden jars (an early type of capacitor) after a battery of cannon. 
Although an early form of electrochemical battery may have been used in 
antiquity, the modern development of batteries started with the Voltaic pile, 
invented by the Italian physicist Alessandro Volta in 1800. Since then, batteries 
have gained popularity as they became portable and useful for many purposes. 
The widespread use of batteries has created many environmental concerns, such 
as toxic metal pollution. Many reclamation companies recycle batteries to 
reduce the number of batteries going into landfills. 
Exercise 4: Are these sentences true (T) or false (F)? 
1. A battery is two or more electrochemical cells which store electrical energy 
and make it available as chemical energy. 
2. Internal chemistry, current drain and temperature are factors that contribute to 
a battery's characteristics. 
3. A primary battery is rechargeable while a secondary is disposable. 
4. In primary batteries, the chemical reactions are reversible while in secondary 
batteries, the chemical reactions are irreversible. 
5. Secondary batteries can be charged and discharged many times before 
wearing out. 
6. An early form of electrochemical battery was invented by the Italian physicist 
Alessandro Volta in 1800 
7. Since the invention of the Voltaic pile, batteries have gained popularity as 
they became portable and useful for many purposes. 
8. One of the environmental concerns caused by use of batteries is toxic metal 
pollution. 
listening: 
Exercise 5 Listen to T.S3 and fill in the blanks with the words given 
Environment chemicals purchase 
Landfills regulations materials 
Services harmful elements 
Mercury 
Batteries - Environmental concerns
Battery manufacture consumes resources and often involves hazardous (1) 
 . Used batteries also contribute to electronic waste. Some areas 
now have battery recycling (2)  available to recover some of the (3) 
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 from used batteries. Batteries may be (4) .. or fatal if 
swallowed. Recycling or proper disposal prevents dangerous (5) .. 
(such as lead, mercury, and cadmium) found in some types of batteries from 
entering the (6)  . In the United States, Americans (7) .. 
nearly three billion batteries annually, and about 179,000 tons of those end up in 
(8) .. across the country. In the United States the Environmental 
Protection Agency’s Mercury-Containing and Rechargeable Battery 
Management Act of 1996, has reduced the amount of (9) . in regular 
household batteries. Recycling programs for lead and cadmium batteries have 
been put in place. Recycling and disposal (10) .. may in the future 
apply to alkaline and nickel-metal hydride batteries. 
Language work 
We use CAN to express possiblity or ability: S + CAN + V infinitive 
E.g 
We can produce electricity using a generator. 
Exercise 6 Match a line in A with a line in B to make meaningful 
sentences. 
A B 
1. We can recharge a. light bulbs to either AC or DC sources. 
2. We can extended b. a simple wet zinc-carbon battery in the laboratory 
using dilute sulphuric acid as an electrolyte solution. 
3. We can make c. the simple half wave rectifier in two versions with 
the diode pointing in opposite directions. 
4. We can connect d. secondary batteries by applying electrical current. 
5. We can build e. battery life by storing the batteries at a low 
temperature. 
When we change the sentence into passive, we can use the fomula: 
S + CAN + BE + PAST PARTICIPAL 
E.g. 
Active: We can produce electricity using a generator. 
Passive: Electricity can be produced using a generator. 
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Exercise 7 Change the following sentences into passive 
1. We can recharge secondary batteries by applying electrical current. 
2. We can extend battery life by storing the batteries at a low temperature. 
3. We can make a simple wet zinc-carbon battery in the laboratory using 
dilute sulphuric acid as an electrolyte solution. 
4. We can connect light bulbs to either AC or DC sources. 
5. We can build the simple half wave rectifier in two versions with the diode 
pointing in opposite directions. 
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 Unit 8 Incandescent light bulb 
Vocabulary and Pronunciation 
Exercise 1 Match English terms and Vietnamese translations 
English Vietnamese 
1. incandescence bóng thủy tinh 
2. filament quang phổ liên tục 
3. glass bulb dây tóc 
4. headlamp đèn huỳnh quang 
5. tungsten nóng sáng 
6. fluorescent light đui cài 
7. high-intensity ánh sáng nhìn thấy 
8. inert gas vonfram 
9. continuous spectrum cường độ cao 
10. visible light đèn pha 
11. screw base khí trơ 
12. bayonet base tiếp xúc 
13. leak (n,v) rò rỉ 
14. insulation cách (điện ... centrically) 
2. directly connected resistor (A resistor which is connected directly) 
3. positively charged atom (An atom which carries positive charge) 
4. electrically operated mechanism (A mechanism which is operated 
electrically) 
5. manually operated bridge (A bridge which is operated manually) 
6. eletromagnetically coupled detector (A detector which is coupled 
eletromagnetically) 
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 Unit 9 Circuit breaker 
Vocabulary and Pronunciation 
Exercise 1 Match English terms and Vietnamese translations 
English Vietnamese 
1. arc lỗi, trục trặc, hư hỏng 
2. circuit breaker bộ biến đổi, biến thế, biến áp 
3. compressed air đoản mạch, ngắn mạch 
4. electrical circuit công tắc 
5. fault không khí nén 
6. fuse mạch điện 
7. latch cắt điện, cầu giao 
8. overload hồ quang 
9. Relay cơ cấu đóng mạch, chuyển mạch 
10. self-contained chốt, then 
11. short circuit độc lập, có đủ các bộ phận 
12. Spring Quá tải 
13. switch rơ le 
14. switchgear lò xo 
15. transformer cầu chì 
Exercise 2 T.S 1 Listen and practise 
1. arc 6. fuse 11. short circuit 
2. circuit breaker 7. latch 12. spring 
3. compressed air 8. overload 13. switch 
4. electrical circuit 9. relay 14. switchgear 
5. fault 10. self-contained 15. transformer 
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Exercise 3 T.S 2 Listen and complete the sentences by selecting the correct 
word from the box to fill in the gap 
Transformer fuses short circuit 
circuit breakers switch spring 
electrical circuit Relay switchgear 
1. An . is a path which electrons from a voltage or current source 
follow. 
2. A  usually consists of two coils of wire wound on the same 
core. 
3. A  allows a current along a different path from the one 
intended. 
4. A  is an electrical . that opens and closes under the control 
of another electrical circuit. 
5. The term  refers to the combination of electrical disconnects, 
.. and  used to isolate electrical equipment. 
Listening 
Exercise 4 Listen to T.S3 and fill in the blanks with the words given 
Operation circuits replaced 
Application switch overload 
fuses short-circuits switchgear 
A 2 pole miniature circuit breaker 
Photo of inside of a circuit breaker 
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Circuit Breakers 
A circuit breaker is an automatically-operated electrical (1)  
designed to protect an electrical circuit from damage caused by (2) . 
or short circuit. Unlike a fuse, which operates once and then has to be (3) 
 , a circuit breaker can be reset either manually or automatically to 
resume normal (4) .. . Circuit breakers are made in varying sizes, 
from small devices that protect an individual household appliance up to large (5) 
. designed to protect high voltage (6)  feeding an entire 
city. 
An early form of circuit breaker was described by Edison in an 1879 patent (7) 
 , although his commercial power distribution system used (8) 
. . Its purpose was to protect lighting circuit wiring from accidental 
(9) . and overloads. 
reading 
Operation of Circuit Breakers
All circuit breakers have common features in their operation, although details 
vary substantially depending on the voltage class, current rating and type of the 
circuit breaker. 
The circuit breaker must detect a fault condition; in low-voltage circuit 
breakers this is usually done within the breaker enclosure. Circuit breakers for 
large currents or high voltages are usually arranged with pilot devices to sense a 
fault current and to operate the trip opening mechanism. The trip solenoid that 
releases the latch is usually energized by a separate battery, although some high-
voltage circuit breakers are self-contained with current transformers, protection 
relays, and an internal control power source. 
Once a fault is detected, contacts within the circuit breaker must open to 
interrupt the circuit; some mechanically stored energy within the breaker is used 
to separate the contacts, although some of the energy required may be obtained 
from the fault current itself. The stored energy may be in the form of springs or 
compressed air. Small circuit breakers may be manually operated; larger units 
have solenoids to trip the mechanism, and electric motors to restore energy to 
the springs. 
The circuit breaker contacts must carry the load current without excessive 
heating, and must also withstand the heat of the arc produced when interrupting 
the circuit. Contacts are made of copper or copper alloys, silver alloys, and other 
materials. Service life of the contacts is limited by the erosion due to 
interrupting the arc. Miniature circuit breakers are usually discarded when the 
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contacts are worn, but power circuit breakers and high-voltage circuit breakers 
have replaceable contacts. 
When a current is interrupted, an arc is generated - this arc must be 
contained, cooled, and extinguished in a controlled way, so that the gap between 
the contacts can again withstand the voltage in the circuit. Different circuit 
breakers use vacuum, air, insulating gas, or oil as the medium in which the arc 
forms. 
Exercise 5: Are the following sentences true (T) or false (F)? 
1. All circuit breakers have common features in their operation, but details 
are not always the same. 
2. In low-voltage circuit breakers a fault condition is detected within the 
breaker enclosure. 
3. The only function of pilot devices is to sense a fault current. 
4. The trip solenoid that releases the latch is self-contained with current 
transformers, protection relays, and an internal control power source. 
5. Contacts within the circuit breaker must open to interrupt the circuit when 
some mechanically stored energy within the breaker is used to separate 
the contacts. 
6. The circuit breaker contacts must withstand the heat of the arc produced 
when interrupting the circuit. 
7. The erosion due to interrupting the arc limits the service life of the 
contacts. 
8. Miniature circuit breakers are usually replaced when the contacts are 
worn. 
9. When a current is interrupted, an arc is extinguished in a controlled way 
by the current. 
10. Vacuum, air, insulating gas, or oil can be used in different circuit 
breakers. 
Language work: Noun phrase (2) 
A noun phrase in English may take the following structure: 
Noun + Past Participle + Noun 
E.g: A hand operated valve 
The noun phrase ‘A hand operated valve’ means “a valve which is operated by 
hand” 
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Exercise 6 Now convert each of the following clauses into a noun phrase 
E.g: 
A valve which is operated by hand 
Æ a hand operated valve 
1. transformer which is cooled by air 
2. engineering which is aided by a computer 
3. switchgear which is insulated by gas 
4. end which is sprayed with metal 
5. valve which is operated by a motor 
6. screen which is coated with phosphor 
Exercise 7 Translate the noun phrases into Vietnamese 
E.g: hand operated valve (valve which is operated by hand) 
Æ van được thao tác bằng tay 
1. air-cooled transformer (transformer which is cooled by air) 
2. computer-aided enginnering (engineering which is aided by a computer) 
3. gas-insulated switchgear (switchgear which is insulated by gas) 
4. metal-sprayed end (metal sprayed end) 
5. motor-operated valve (valve which is operated by a motor) 
6. phosphor-coated screen (screen which is coated with phosphor) 
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 Unit 10 Rectifier 
Vocabulary and Pronunciation 
Exercise 1 Match English terms and Vietnamese translations 
English Vietnamese 
1. alternating current dạng sóng 
2. anode bộ chỉnh lưu, bộ nắn dòng 
3. arc dòng xoay chiều 
4. cathode chỉnh lưu cả sóng 
5. center-tapped hồ quang 
6. direct current phân cực, cực tính 
7. full-wave rectification cực dương 
8. half wave rectification nửa dương 
9. inverter đèn chân không 
10. negative half dòng một chiều 
11. polarity cực âm 
12. positive half nửa âm 
13. rectifier bộ đảo điện, bộ đảo lưu 
14. vacuum tube trích giữa 
15. waveform chỉnh lưu nửa sóng 
Exercise 2 T.S 1 Listen and practise 
1. alternating current 6. direct current 11. polarity 
2. anode 7. full-wave rectification 12. positive half 
3. arc 8. half wave rectification 13. rectifier 
4. cathode 9. inverter 14. vacuum tube 
5. center-tapped 10. negative half 15. waveform 
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Exercise 3 T.S 2 Listen and complete the sentences by selecting the correct 
word from the box to fill in the gap. 
alternating current direct current anode 
arc center-tapped rectifier 
cathode inverter vacuum tube 
1. A  transformer is a transformer with a tap in the middle of 
the secondary winding. 
2. An .. is an electrical device that converts  to 
. 
3. Some special function  are filled with low-pressure gas. 
4. An .. is an electrode through which electric current flows into a 
polarized electrical device. 
5. A  is an electrode through which electric current flows out of a 
polarized electrical device. 
listening: 
Exercise 4 Listen to T.S3 and fill in the blanks with the words given 
detectors convert diodes components arrangement
difference converts rectification development function 
A rectifier is an electrical device that (1)  alternating current (AC) 
to direct current (DC), a process known as (2) .. . Rectifiers have many 
uses including as components of power supplies and as (3) .. of radio 
signals. Rectifiers may be made of solid state diodes, vacuum tube diodes, 
mercury arc valves, and other (4) . . A device which performs the 
opposite (5) .. (converting DC to AC) is known as an inverter. When 
only one diode is used to rectify AC (by blocking the negative or positive 
portion of the waveform), the (6)  between the term diode and the 
term rectifier is merely one of usage, i.e., the term rectifier describes a diode 
that is being used to (7) .. AC to DC. Almost all rectifiers comprise 
a number of diodes in a specific (8)  for more efficiently converting 
AC to DC than is possible with only one diode. Before the (9)  of 
silicon semiconductor rectifiers, vacuum tube (10)  and copper(I) 
oxide or selenium rectifier stacks were used. 
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Reading 
Half-wave rectification
In half wave rectification, either the positive or negative half of the AC wave is 
passed, while the other half is blocked. Because only one half of the input 
waveform reaches the output, it is very inefficient if used for power transfer. 
Half-wave rectification can be achieved with a single diode in a one phase 
supply, or with three diodes in a three-phase supply. 
Full-wave rectification
A full-wave rectifier converts the whole of the input waveform to one of 
constant polarity (positive or negative) at its output. Full-wave rectification 
converts both polarities of the input waveform to DC (direct current), and is 
more efficient. However, in a circuit with a non-center tapped transformer, four 
diodes are required instead of the one needed for half-wave rectification. (See 
semiconductors, diode). Four rectifiers arranged this way are called a diode 
bridge or bridge rectifier: 
For single-phase AC, if the transformer is center-tapped, then two diodes back-
to-back (i.e. anodes-to-anode or cathode-to-cathode) form a full-wave rectifier 
(in this case, the voltage is half of that for the non-tapped bridge circuit above, 
and the diagram voltages are not to scale). 
A very common vacuum tube rectifier configuration contained one cathode and 
twin anodes inside a single envelope; in this way, the two diodes required only 
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one vacuum tube. The 5U4 and 5Y3 were popular examples of this 
configuration. 
Full-wave rectifier, with vacuum tube having two anodes. 
For three-phase AC, six diodes are used. Typically there are three pairs of 
diodes, each pair, though, is not the same kind of double diode that would be 
used for a full wave single-phase rectifier. Instead the pairs are in series (anode 
to cathode). Typically, commercially available double diodes have four 
terminals so the user can configure them as single-phase split supply use, for 
half a bridge, or for three-phase use. 
Exercise 5: Are the following sentences true (T) or false (F)? 
1. In half wave rectification, only one half of the AC wave is passed, while 
the other half is blocked. 
2. Half-wave rectification can only be achieved with a single diode in a one 
phase supply. 
3. Full-wave rectification converts both halves of the AC wave to DC. 
4. Full-wave rectification is more efficient than half-wave rectification. 
5. In half-wave rectification, more diodes are used than in full-wave 
rectification. 
6. A recfifier with a center-tapped transformer requires more diodes than a 
rectifier with a non-center tapped transformer. 
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7. A recfifier with a center-tapped transformer is more efficient than a 
rectifier with a non-center tapped transformer. 
8. A common vacuum tube rectifier configuration contained one anode and 
twin cathodes inside a single envelope. 
9. For three-phase AC, three pairs of diodes are used. 
Language work: Noun phrase (3) 
A noun phrase in English may take the following structure: 
Noun + Present Participle + Noun 
E.g: A current-carrying conductor 
The noun phrase ‘A current-carrying conductor’ means “a conductor which is 
carrying a current” 
Exercise 6 Now convert each of the following clauses into a noun phrase 
E.g: a conductor which is carrying a current 
Æ A current-carrying conductor 
1. radar which can find direction 
2. material which conducts current 
3. material which insulates heat 
4. device which can sense temperature 
5. pump which feeds oil 
6. system which processes data 
Exercise 7 Translate the noun phrase into Vietnamese 
A current-carrying conductor (a conductor which is carrying a current) 
Æ vật dẫn mang dòng 
1. direction finding radar (radar which can find direction) 
2. current conducting material (material which conducts current) 
3. heat insulating material (material which insulates heat) 
4. temperature sensing device (device which can sense temperature) 
5. oil feeding pump (pump which feeds oil) 
6. data processing system (which processes data) 
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REFERENCES 
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