Английский язык для моряков / Труханова Англ для моряков

Principal protective means are those the insulation of which is reliable enough to withstand a working

voltage of an electrical set and makes it possible to touch hot-line current-leading parts. On electrical sets with voltage up to 1,000 V the above mentioned means are the following: insulating gloves, tools equipped with insulated handles, voltage indicators, insulating and clip-on instruments.

Additional protective means are not designed to ensure protect tion against electric shock hazard, but

against a pace voltage and detri-j mental effect of an electric arc and the products of its burning. Sucn means are the following: insulating galoshes and high overshoes, insu-l lating rubber rugs, insulating stands.

There are also auxiliary protective means designed for individu-1 al protection of an operating

personnel against light, thermal and me-j chanical effects. They are protective glasses, gas-masks, special gaunt-] lets etc.

Electricity can be dangerous and even fatal for those who do not understand the simple rules of safety.

There are many fatal accidents involving by a well-trained personnel who violates the basic rules of personal safety.

Currents above 100 milliamperes or only one tenth of an ampere are fatal. A workman who has contacted currents above 200 milliamperes may live to see another day if given rapid treatment. Currents below 100 milliamperes can be serious and painful. A safe rule: Do not place yourself in a position to get any kind of a

shock.

Here are some rules that should be observed to avoid electric shocks.

1.Be sure of the conditions of the equipment and the dangers present before working on a piece of equipment. Many sportsmen are killed by supposedly unloaded guns; many technicians are killed by supposed "dead" circuits.

2.Never rely on safety devices such as fuses, relays and interlock systems to protect you. They may not be working and may fail to protect when most needed.

3.Never remove the grounding prong of a three wire input plug. This eliminates the grounding feature of the equipment making it a potential shock hazard.

4.Do not work on a cluttered bench. A disorganized mess of connecting leads, components and

tools only leads to careless thinking, shortcircuits, shocks and accidents. Develop habits of systemized and organized procedures of work.

5. Do not work on wet floors. Your contact resistance to ground is substantially reduced. Work on a

rubber mat or an insulated floor.

6. Do not work alone. It's just good sense to have someone around to shut off the power, to give artificial respiration and to call a doctor.

7. Work with one hand behind you or on your pocket. A current between two members crosses your heart and can be lethal. A wise technician always works with one hand.

8. Never talk to anyone while working. Don't let yourself be distracted. Also, don't you talk to anyone, if he is working on dangerous equipment. Don't be the cause of an accident.

9. Always move slowly when working around electrical circuits. Violent and rapid movements lead to accidental shocks and short circuits.

QUESTIONS

1.In what case can electricity be dangerous and fatal?

2.What currents are fatal?

Why must a workman not rely on fuses, relays and interlock systems? Why is it so important not to remove the grounding prong of a three wire input plug?

What does a cluttered bench lead to?

Why is it so necessary for an electrician to work on a rubber mat? Should an electrician work alone or have someone around? Why is it important for an electrician to avoid violent and rapid movements?

EXERCISES

/. Check yourself in your vocabulary.

What do you call:

1.the process of taking care of electrical mechanisms on board ship?

2.the actions you fulfill when you want to protect yourself?

3.the tools you can carry from one place to another in your hands?

4.the people who take care of any type of equipment?

5.the things you put on your hands when you want to let yourself touch hot-line?

6.the things you put on your feet to protect yourself against a pace voltage?

7.the means which ensure your individual protection?

8.the things you put on your face to protect your lungs and skin?

II. Make sure you have properly understood the meaning of the text:

1. Electrical traumatism is caused by:

a) electrical safety;

b)portable accessory;

c)formal instructing on safe methods of work.

2. The use of electrical energy is connected with:

a)possible fires;

b)thermal effect of an electric current;

3.

4.

5.

6.

7.

8.

c) environmental conditions.

3.The normal state of shipboard electrical equipment is broken when:

a)you do not put on special gauntlets;

b)insulation can't withstand a working voltage;

c)damages occur.

4.When the normal state of shipboard electrical equipment is broken:

a)clip-on instruments are used;

b)protective glasses are put on;

c)arc and spark discharges emerge.

5.Principal protective means are those which:

a)protect against a pace voltage;

b)help to withstand a working voltage;

c)are designed for individual protection.

6.Additional protective means are those which:

a)protect against light, thermal and mechanical effects;

b)protect against the effect of an electric arc;

c)make it possible to touch hot-line parts.

III.Mind the grammatical construction of Present Simple Passive.

1.Add the Past Participle to the following sentences taken from the text. Choose from the verbs in the box. Use each verb once only:

exceed fixed rates.

2)Additional protective means are n o t . . . to ensure protection from electric shock hazard.

4)If the Rules of electrical maintenance and safety are not . . . , the normal state of the equipment is . . . .

5)The use of electrical energy is not only . . . with danger of injury of an operating personnel.

2. Put the verb in the correct form using Present Simple Active Present Simple Passive:

If the Rules of shipboard electrical maintenance and safety . . (not observe), if damages . . . (occur) and the environment conditions . . . (affect) the electrical equipment, its normal s'

. . . (break).

Isolating gloves . . . (use) as one of the principal protects means.

Insulating rubber rugs . . . (protect) against detrimental effr of an electric arc.

Insulation of principal protective means . . (withstand* working voltage of an electrical set. The operating personnel of an electrical set may . . . (put insulating galoshes.

3.Translate into English using either positive or negative for' of Imperative:

Убедитесь в том, что оборудование исправно.

Никогда не убирайте заземляющий штырь трехфазного вх ного штепселя.

Всегда двигайтесь медленно, когда работаете в окружении эд^ трических цепей.

Ни с кем не разговаривайте во время работы.

Не работайте в одиночку.

Попытайтесь вспомнить правила эксплуатации электрообо дования и техники безопасности.

Никогда не работайте на мокром полу.

UNIT 10 TROUBLESHOOTING

1. TROUBLESHOOTING OF ELECTRICAL COMPONENTS

The causes for electrical equipment to breakdown are heat, moisture, ingress of dirt and other contaminants, vibration, and poor installation.

Heat increases the resistance of the circuit and thus increases the current causing the material to expand, dry out, crack, and wear down much quicker. Sooner or later the device will be broken.

Moisture also causes circuit to draw more current and eventually breakdown. Moisture like water and liquids causes expansion, warping of the material as well as abnormal current flow or short circuit.

Dirt and other contaminants are fumes, vapours, grease, oils etc. They cause electrical device to clog or gum up and operate abnormally until breakdown.

Vibration and poor installation can also cause the above mentioned types of breakdown soon. The breakdown causes listed above result in a number of detrimental effects involving

short circuit, grounded circuit and mechanical breakdowns. These latter are often a result of too

much friction, wear or vibration which moving parts like broken belts, worn contacts, worn bearings, loose

belts etc. cause.

Here are some basic methods used in troubleshooting electrical or electronic devices.

1.Voltage measurement of a circuit, which is usually taken by ing a voltmeter. The electrician must always connect a voltmeter in p allel with the circuit when measuring voltage.

2.Amperage measurement of a circuit, which is usually take by using an ammeter or a clam-on ammeter that locates commq circuit faults, such as short, open or grounded circuits. The electrici must always connect an ammeter in series with the circuit whe measuring current.

3.Resistance measurement with which an ohmmeter is used to m sure the continuity of a circuit or a component. The electrician must r member to shut off the power before using an ohmmeter.

4.Substitution, which is a technique of replacing a suspected faul component with a good spare one.

5.Bridging is employed when an electrician suspects a component like a capacitor to be faulty and places a good component across a sus; pected faulty one from the circuit.

Other methods of troubleshooting are those of heating, freezing) using testers, resoldering, adjusting, bypassing etc. They are all effe tive in locating faults of every component in a circuit.

VOCABULARY

troubleshooti нахождение и устранение

мостовой схеме

freezing замораживание

resoldering перепайка

by-passing шунтирование

QUESTIONS

1.What are the causes for electrical equipment to breakdown?

2.Why does heat cause the material to expand, dry out, crack and wear down?

3.What does moisture cause?

4.Do you know any contaminants? What are they?

5.What arc detrimental ettects that arc caused by heat, moisture, dirt, vibration?

6.What are mechanical breakdowns caused by?

7.What way of connecting a voltmeter does the electrician necessarily use when measuring voltage?

8.What way of connecting an ammeter does the electrician necessarily use when measuring current?

9.What is a clam-on ammeter used for?

10.What must the electrician remember to shut off before measuring resistance?

11.What kind of technique is substitution?

12.What method is called bridging?

13.What are other methods used in troubleshooting electrical devices?

2. TROUBLESHOOTING OF D.C. MOTORS

VOCABULARY