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Метод. пособие англ. яз. СЭ-3.docx
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Vocabulary.

Occasional repair – периодический ремонт

Preventive maintenance schedule плановое профилактическое обслуживание

Split-phase motor – электродвигатель с расщепленной фазой

End bell – конечный конус, раструб

Alignment – выравнивание, регулировка

The ends may be out of the line

Slot - паз

To lock – блокировать, стопорить

Pole piece – полюсной башмак, полюсной наконечник

The end play – осевой зазор, осевой люфт

Pitch - шаг

Exercises.

  1. Find the answers to the questions of the left column.

1. What can troubleshooting and repair motor be eliminated by?

2. What is the preventive maintenance?

3. What procedures does the preventive maintenance include?

4. What is the first check of the troubles in a split-phase motor?

5. What measuring device may be used to check the connections from the terminal block to the frame?

6. What is the reason of the ground in the centrifugal switch?

7. By what sings can the burned winding be recognized?

8. What measuring device is used to check the resistance in the coil?

9. By what can an open circuit be caused ?

10. What can too much end play in the rotor shaft cause?

11. Why mustn’t you touch the terminals after the charging process?

12. What sign should show if the capacitor is good?

a) Grease that has accumulated from over- greasing.

b) A break in a wire in the winding, or by the centrifugal switch not closing properly when the motor is at a standstill.

c) Taking care  of  the  trouble  before  it happens.

d) Proper voltage at the terminal block

e) Cause the rotating part of the centrifugal switch to stop at a point where it allows the contacts on the stationary part of the switch to stand open.

f) A preventive maintenance schedule.

g) A strong spark

h) An ohmmeter or megger.

i) Oiling, greasing, cleaning, keeping the area around the equipment clean, and seeing that the  equipment  has  the  proper  protective fuses   and   overload   protection

j) An ohmmeter

k) Serious injury may result from the stored charge.

l) By its smell and the burned appearance.

  1. Complete the sentences.

1. If you find a ground in this test, …

2. If the first test does not show a ground in the motor,…

3.  If the rotor turns freely…

4. If the rotor turns freely with no voltage applied, but locks when it is applied,…

5. If the trouble is a short, …

6. If the starting winding is burned,…

7. Should the rotor have more than 1/64-inch end play, …

8. If the motor windings are severely damaged, …

9. To test a capacitor …

10. If the fuse does not burn out,…

a)… place fiber washers on the shaft to line the rotor up properly.

b)… remove the end bell with the terminal block and centrifugal switch and separate the starting winding and running winding and make another ground check on each of these windings.

c)… connect the motor to the source of power and again check to see that the rotor turns freely when energized.

d)… you will know that the bearings are worn enough to allow the iron in the rotor to make contact with the iron in the pole pieces.

e)… , leave the capacitor connected to the line for a few seconds to build up a charge. 

f)… remove the motor leads from the capacitor and connect the capacitor in series with a 10-amp fuse across a 110- volt line.

g)… check to see that the rotor revolves freely.  

h)… either the fuse will blow or the winding will smoke when the motor is connected to the line.

i)… the motor must be sent to a motor shop for repairs.

j)… it can usually be replaced without disturbing the running winding, but check closely to be sure that the running winding is not damaged.