Where a thermal-acting breaker is required to be used in an area of unusually high, low, or constantly fluctuating temperatures, an ambient compensating element must be used. This element consists of a ______________. A. cylindrical spring on the contact arm B. conical spring on the contact arm C. second bimetal element D. second electromagnet

Where a thermal-acting breaker is required to be used in an area of unusually high, low, or constantly fluctuating temperatures, an ambient compensating element must be used. This element consists of a ______________. A. cylindrical spring on the contact arm B. conical spring on the contact arm C. second bimetal element D. second electromagnet
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Answer: C
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Related questions

In addition to short circuits and sustained overloads, fuses are likely to blow due to _____________. A. loose fuse clips B. low ambient temperatures C. low contact resistance D. all of the above

Description : In addition to short circuits and sustained overloads, fuses are likely to blow due to _____________. A. loose fuse clips B. low ambient temperatures C. low contact resistance D. all of the above

Last Answer : Answer: A

In addition to testing the calibration of a circuit breaker, maintenance should include all of the following EXCEPT ______________. A. changing out of magnetic elements and thermal heaters yearly B. checking for corrosion, accumulation of dirt and thermal fatigue C. inspecting for loose or missing parts D. making sure foreign matter does not block tripping element

Description : In addition to testing the calibration of a circuit breaker, maintenance should include all of the following EXCEPT ______________. A. changing out of magnetic elements and thermal heaters yearly B. ... for loose or missing parts D. making sure foreign matter does not block tripping element

Last Answer : Answer: A

Which of the following conditions indicates that a lead-acid battery is being charged too rapidly? A. Sparks occurring at the positive terminal. B. Unusually high electrolyte specific gravity. C. Low plate potentials being developed. D. Excessively high temperatures and gassing rates.

Description : Which of the following conditions indicates that a lead-acid battery is being charged too rapidly? A. Sparks occurring at the positive terminal. B. Unusually high electrolyte specific gravity. C. Low plate potentials being developed. D. Excessively high temperatures and gassing rates.

Last Answer : Answer: D

In the illustration, the the device E is the______. EL-0033 A. bimetal strip B. moving contact C. trip bar D. handle

Description : In the illustration, the the device E is the______. EL-0033 A. bimetal strip B. moving contact C. trip bar D. handle

Last Answer : Answer: C

Magnetic controller contacts may become welded together during operating conditions as a result of _____________. A. high spring pressure B. high ambient temperature C. an open coil D. low voltage on operating coil

Description : Magnetic controller contacts may become welded together during operating conditions as a result of _____________. A. high spring pressure B. high ambient temperature C. an open coil D. low voltage on operating coil

Last Answer : Answer: D

A molded-case circuit breaker provides protection against short circuits by using a/an ________________. A. electromagnet B. shading coil C. arc quencher D. burn away strip

Description : A molded-case circuit breaker provides protection against short circuits by using a/an ________________. A. electromagnet B. shading coil C. arc quencher D. burn away strip

Last Answer : Answer: A

A molded-case breaker provides protection against short circuits by using a/an ____________. A. shading coil B. arc quencher C. electromagnet D. holding coil

Description : A molded-case breaker provides protection against short circuits by using a/an ____________. A. shading coil B. arc quencher C. electromagnet D. holding coil

Last Answer : Answer: C

The insulation of electric generators during short idle periods should be _____________. A. allowed to cool slowly to ambient temperatures B. flashed with direct current to remove any residual magnetism C. kept warm by using strip or space heaters D. relieved of all capacitive charge by grounding the conductors

Description : The insulation of electric generators during short idle periods should be _____________. A. allowed to cool slowly to ambient temperatures B. flashed with direct current to remove any residual ... using strip or space heaters D. relieved of all capacitive charge by grounding the conductors

Last Answer : Answer: C

On large generators, space heaters are used to ____________. A. keep the machine at ambient tmperature of the machinery space B. maintain rotor and stator winding temperatures above the dew point to prevent the formation of condensation C. prevent condensation in the lube oil D. prevent electrolysis due to condensation in the bearings

Description : On large generators, space heaters are used to ____________. A. keep the machine at ambient tmperature of the machinery space B. maintain rotor and stator winding temperatures above the dew point ... C. prevent condensation in the lube oil D. prevent electrolysis due to condensation in the bearings

Last Answer : Answer: B

Magnetic controller contacts may become welded together during operation because of _____________. A. excessive magnetic gap B. low contact pressure C. an open coil D. excessive ambient temperature

Description : Magnetic controller contacts may become welded together during operation because of _____________. A. excessive magnetic gap B. low contact pressure C. an open coil D. excessive ambient temperature

Last Answer : Answer: B

Magnetic controller contacts may become welded together during operation due to _____________. A. an open coil B. low contact pressure C. excessive ambient temperature D. excessive magnetic gap

Description : Magnetic controller contacts may become welded together during operation due to _____________. A. an open coil B. low contact pressure C. excessive ambient temperature D. excessive magnetic gap

Last Answer : Answer: B

How will a molded-case circuit breaker react after it has tripped, as a result of an overloaded circuit? A. The breaker will trip again if immediately reset. B. The breaker handle will lock in the OFF position. C. The breaker handle will lock in the tripped position until the thermal element cools down. D. The breaker handle cannot be moved to the OFF position until the thermal element cools down.

Description : How will a molded-case circuit breaker react after it has tripped, as a result of an overloaded circuit? A. The breaker will trip again if immediately reset. B. The breaker handle will lock in ... down. D. The breaker handle cannot be moved to the OFF position until the thermal element cools down.

Last Answer : Answer: A

Consider the following statements 1. Large cold storage plants use ammonia as refrigerant while domestic refrigerators use chlorofluorocarbons. 2. Ammonia can be liquefied at ambient temperatures and at low pressures. 3. Chlorofluorocarbons are air pollutants. The correct statement(s) is/are: (a) 1 and 3 only (b) 2 and 3 only (c) 1, 2 and 3 (d) 3 only

Description : Consider the following statements 1. Large cold storage plants use ammonia as refrigerant while domestic refrigerators use chlorofluorocarbons. 2. Ammonia can be liquefied at ambient temperatures and at low pressures. 3. Chlorofluorocarbons are ... 3 only (b) 2 and 3 only (c) 1, 2 and 3 (d) 3 only

Last Answer : Ans:(a)

During maintenance of circuit breakers, _______________. A. always smooth roughened contact surfaces with a file B. never pass more than rated breaker current through the overload heater element C. inspect for wear and misalignment of main contacts D. assume heater elements installed are of correct size

Description : During maintenance of circuit breakers, _______________. A. always smooth roughened contact surfaces with a file B. never pass more than rated breaker current through the overload heater element C. ... wear and misalignment of main contacts D. assume heater elements installed are of correct size

Last Answer : Answer: C

Electric circuits are protected against overloads and short circuits by means of a/an ______________. A. circuit breaker B. amplifier C. diode D. capacitor

Description : Electric circuits are protected against overloads and short circuits by means of a/an ______________. A. circuit breaker B. amplifier C. diode D. capacitor

Last Answer : Answer: A

Electrical circuits are protected against overheating by means of a/an ______________. A. circuit breaker B. amplifier C. diode D. capacitor

Description : Electrical circuits are protected against overheating by means of a/an ______________. A. circuit breaker B. amplifier C. diode D. capacitor

Last Answer : Answer: A

A low voltage source is being used for testing armature coils. A coil short circuit will be indicated by a _______. A. high voltage reading, while the other coil readings will have an equal or lower value B. low or zero voltage reading, while the other coils will have higher readings C. fluctuating voltmeter reading, while the other coil readings are steady D. steady voltmeter reading, while the other coil readings are fluctuating

Description : A low voltage source is being used for testing armature coils. A coil short circuit will be indicated by a _______. A. high voltage reading, while the other coil readings will have an ... the other coil readings are steady D. steady voltmeter reading, while the other coil readings are fluctuating

Last Answer : Answer: B

Which of the following statements regarding evacuated tube collectors (ETC) are true? i) ETC is used for high temperatures upto 150oC ii) because of use of vacuum between two concentric glass tube, higher amount of heat is retained in ETC iii) heat loss due to conduction back to atmosphere from ETC is high iv) performance of evacuated tube is highly dependent upon the ambient temperature i & iii b) ii & iii c) i & iv d) i & ii

Description : Which of the following statements regarding evacuated tube collectors (ETC) are true? i) ETC is used for high temperatures upto 150oC ii) because of use of vacuum between two concentric glass tube, higher amount of heat is ... upon the ambient temperature i & iii b) ii & iii c) i & iv d) i & ii

Last Answer : d) i & ii

For a given ambient air temperature with increase in the thickness of insulation of a hot cylindrical pipe, the rate of heat loss from the surface would (A) Decrease(B) Increase(C) First decrease and then increase(D) First increase and then decrease

Description : For a given ambient air temperature with increase in the thickness of insulation of a hot cylindrical pipe, the rate of heat loss from the surface would (A) Decrease (B) Increase (C) First decrease and then increase (D) First increase and then decrease

Last Answer : (D) First increase and then decrease

A lead-acid battery cell sustaining a short circuit _______. A. will be indicated by lime accumulation on the terminal posts B. will have unusually high cell voltage C. will become excessively heated while being charged D. cannot be completely discharged under load

Description : A lead-acid battery cell sustaining a short circuit _______. A. will be indicated by lime accumulation on the terminal posts B. will have unusually high cell voltage C. will become excessively heated while being charged D. cannot be completely discharged under load

Last Answer : Answer: C

A concentric spring consists of 2 sprigs of diameter 10mm and 4mm. The net force acting on the composite spring is 5000N. Find the force acting on each of the two springs. (a) 1232.2N and 3767.8N (b) 786.4N and 4213.6N (c) 689.7N and 4310.3N (d) 645.3N and 4354.7N

Description : A concentric spring consists of 2 sprigs of diameter 10mm and 4mm. The net force acting on the composite spring is 5000N. Find the force acting on each of the two springs. (a) 1232.2N and 3767.8N (b) 786.4N and 4213.6N (c) 689.7N and 4310.3N (d) 645.3N and 4354.7N

Last Answer : (c) 689.7N and 4310.3N

If a DC motor runs hot, the cause may be _____________. A. high mica condition B. low ambient temperature C. clogged ventilation ducts D. an open in the shunt field

Description : If a DC motor runs hot, the cause may be _____________. A. high mica condition B. low ambient temperature C. clogged ventilation ducts D. an open in the shunt field

Last Answer : Answer: C

Which of the listed conditions could indicate the need for cleaning electrical insulation? A. Low ambient temperature B. Low operating temperature C. High dielectric strength D. Low megger readings

Description : Which of the listed conditions could indicate the need for cleaning electrical insulation? A. Low ambient temperature B. Low operating temperature C. High dielectric strength D. Low megger readings

Last Answer : Answer: D

When troubleshooting a magnetic controller, it is found that the contacts are welded together. The most probable cause is _____________. A. excessive operation at low load B. high ambient temperature C. low voltage on the operating coil D. high voltage on the operating coil

Description : When troubleshooting a magnetic controller, it is found that the contacts are welded together. The most probable cause is _____________. A. excessive operation at low load B. high ambient temperature C. low voltage on the operating coil D. high voltage on the operating coil

Last Answer : Answer: C

Which of the following statements describes the significance of ambient temperature in relation to the service life of electronic components? A. Ambient temperature should be as high as possible to drive off moisture. B. Increased ambient temperature decreases the service life of electronic components. C. Ambient temperature is not significant as long as the relative humidity is kept low. D. A reduced ambient temperature causes a corresponding reduced service life.

Description : Which of the following statements describes the significance of ambient temperature in relation to the service life of electronic components? A. Ambient temperature should be as high as possible to drive ... is kept low. D. A reduced ambient temperature causes a corresponding reduced service life.

Last Answer : Answer: B

The torque produced by a DC motor armature is the product of the force acting at the armature surface multiplied by _____________. A. work done by the armature in one revolution B. effective armature diameter at which the force acts C. maximum moment arm at the center of rotation of the armature D. perpendicular distance to its center of rotation

Description : The torque produced by a DC motor armature is the product of the force acting at the armature surface multiplied by _____________. A. work done by the armature in one revolution B. effective ... arm at the center of rotation of the armature D. perpendicular distance to its center of rotation

Last Answer : Answer: D

D.C. propulsion motor brush pressure depends on the brush grade used and in practice is set with a ______________. A. multimeter B. manometer C. spring scale D. compound gauge

Description : D.C. propulsion motor brush pressure depends on the brush grade used and in practice is set with a ______________. A. multimeter B. manometer C. spring scale D. compound gauge

Last Answer : Answer: C

The item referred to as a pigtail on a DC motor brush rigging is a/an ______________. A. feather spring B. uninsulated wire C. flexible spring adjuster D. brush holder

Description : The item referred to as a pigtail on a DC motor brush rigging is a/an ______________. A. feather spring B. uninsulated wire C. flexible spring adjuster D. brush holder

Last Answer : Answer: B

Unless it can be shown that a 45°C ambient temperature will not be exceeded, motors within a machinery space must be designed for an ambient temperature of _____________. A. 45°C B. 50°C C. 55°C D. 60°C

Description : Unless it can be shown that a 45°C ambient temperature will not be exceeded, motors within a machinery space must be designed for an ambient temperature of _____________. A. 45°C B. 50°C C. 55°C D. 60°C

Last Answer : Answer: B

In a square and ground helical spring the effective number of turns is incresead by a. 1 b. 2 c. 1.5 d. 0 Ans: b 77. Frequency of the fluctuating load of helical compression spring should be a. lees than natural frequency of vibration b. twenty times the natural frequency of vibration c. slightly greater than the natural frequency d. twenty times less than the natural frequency of vibration

Description : In a square and ground helical spring the effective number of turns is incresead by a. 1 b. 2 c. 1.5 d. 0 Ans: b 77. Frequency of the fluctuating load of helical compression ... vibration c. slightly greater than the natural frequency d. twenty times less than the natural frequency of vibration

Last Answer : d. twenty times less than the natural frequency of vibration

From the standpoint of safety, you should never allow salt water to enter a leadacid storage battery or come in contact with sulfuric acid because ______________. A. the resulting gas is extremely flammable B. the resulting gas is a respiratory irritant that can be fatal C. the primary constituent, sodium, reacts lethally with lead peroxide D. combining salt water with lead-acid creates an invisible gas resulting in severe corrosion

Description : From the standpoint of safety, you should never allow salt water to enter a leadacid storage battery or come in contact with sulfuric acid because ______________. A. the resulting gas is ... peroxide D. combining salt water with lead-acid creates an invisible gas resulting in severe corrosion

Last Answer : Answer: B

If you disconnect and arrange both ends of a three conductor cable, without any contact between the individual conductors, an indicated ohmic value between the ends of a single conductor would indicate ______________. A. continuity of the conductor B. an infinite resistance C. the presence of a partial ground D. that the conductor is not short circuited

Description : If you disconnect and arrange both ends of a three conductor cable, without any contact between the individual conductors, an indicated ohmic value between the ends of a single conductor would indicate ... resistance C. the presence of a partial ground D. that the conductor is not short circuited

Last Answer : Answer: A

What is the purpose of spring charging in 415 V breaker?

Description : What is the purpose of spring charging in 415 V breaker? 

Last Answer : If the breaker is to be closed and tripped manually the closing time and tripping time would vary from person to person. Also it would not be very fast. So spring charging is provided. It ... timings irrespective of the operator and its action is fast and closing and tripping time is very less. 

The schematic diagram shown in the illustration uses symbol 'A' to represent a/an _________. EL-0011 A. non-renewable fuse link B. circuit breaker coil C. overload relay coil D. thermal overload heater

Description : The schematic diagram shown in the illustration uses symbol 'A' to represent a/an _________. EL-0011 A. non-renewable fuse link B. circuit breaker coil C. overload relay coil D. thermal overload heater

Last Answer : Answer: D

The arc resulting from the tripping of a circuit breaker is prevented from damaging the contacts by _____________. A. designing the contacts to open slowly B. directing the arc into an arc chute C. an inverse timed thermal trip for short circuit currents D. instantaneous magnetic trip for overload currents

Description : The arc resulting from the tripping of a circuit breaker is prevented from damaging the contacts by _____________. A. designing the contacts to open slowly B. directing the arc into an ... an inverse timed thermal trip for short circuit currents D. instantaneous magnetic trip for overload currents

Last Answer : Answer: B

Fuses placed in series with a thermal trip-type circuit breaker are used for _____________. A. time-delay protection B. short-circuit protection C. short duration surge protection D. sustained overload protection

Description : Fuses placed in series with a thermal trip-type circuit breaker are used for _____________. A. time-delay protection B. short-circuit protection C. short duration surge protection D. sustained overload protection

Last Answer : Answer: B

What does the arrangement at coordinates '62E' shown in the illustration represent? EL-0099 A. Position recording drum and stylus B. Temperature compensating thyristor C. Miniature bridge rectifier D. Twisted wire pair within a shield

Description : What does the arrangement at coordinates '62E' shown in the illustration represent? EL-0099 A. Position recording drum and stylus B. Temperature compensating thyristor C. Miniature bridge rectifier D. Twisted wire pair within a shield

Last Answer : Answer: D

Silicon diodes designed for a specific reverse breakdown voltage, become useful as an electronic power supply voltage regulator, called _____________. A. tunnel diodes B. hot-carrier diodes C. compensating diodes D. Zener diodes

Description : Silicon diodes designed for a specific reverse breakdown voltage, become useful as an electronic power supply voltage regulator, called _____________. A. tunnel diodes B. hot-carrier diodes C. compensating diodes D. Zener diodes

Last Answer : Answer: D

Which one of the following statements for a dc machine which is provided with inter pole winding (IW) as well as compensating winding (CW) is correct a) Both IW and CW are connected in series with Armature winding b) Both IW and CW are connected in parallel with Armature winding c) IW connected in series but CW is connected in parallel with Armature winding d) CW connected in series but IW is connected in parallel with Armature winding

Description : Which one of the following statements for a dc machine which is provided with inter pole winding (IW) as well as compensating winding (CW) is correct a) Both IW and CW are connected in ... parallel with Armature winding d) CW connected in series but IW is connected in parallel with Armature winding

Last Answer : Ans: Both IW and CW are connected in series with Armature winding

If a magnetic controller contact fails to pick up when the operating coil is energized, one possible cause may be _______________. A. low spring pressure B. low voltage to the coil C. the residual magnetism of the contact faces D. dirty contact faces

Description : If a magnetic controller contact fails to pick up when the operating coil is energized, one possible cause may be _______________. A. low spring pressure B. low voltage to the coil C. the residual magnetism of the contact faces D. dirty contact faces

Last Answer : Answer: B

The main difference between a motor control circuit containing low voltage protection and low voltage release is that the latter contains _____________. A. a magnetic operating coil B. normally open line contacts C. thermal-overload protection D. a momentary-contact start button

Description : The main difference between a motor control circuit containing low voltage protection and low voltage release is that the latter contains _____________. A. a magnetic operating coil B. normally open line contacts C. thermal-overload protection D. a momentary-contact start button

Last Answer : Answer: D

Second glass plate in Michelson ‘s Interferometer is known as A. Extra glass plate C. Simple Glass Plate B. Compensating glass plate D. None of these

Description : Second glass plate in Michelson ‘s Interferometer is known as A. Extra glass plate C. Simple Glass Plate B. Compensating glass plate D. None of these

Last Answer : B. Compensating glass plate

In a faceplate-type motor starter, the starting arm is held in the 'OFF' position by a/an _____________. A. cotter pin B. magnet C. electrical circuit D. strong spring

Description : In a faceplate-type motor starter, the starting arm is held in the 'OFF' position by a/an _____________. A. cotter pin B. magnet C. electrical circuit D. strong spring

Last Answer : Answer: D

In the illustration, the purpose of part B is to _________. EL-0033 A. increase resistance in series with the contacts as they close to prevent arcing B. create a magnetic field in the steel plates that interacts with the arc to cool and extinguish the arc C. cause the contacts to open in the event of an overload D. provide ventilation to the contact when the breaker is close to rated capacity

Description : In the illustration, the purpose of part B is to _________. EL-0033 A. increase resistance in series with the contacts as they close to prevent arcing B. create a magnetic field in the steel ... event of an overload D. provide ventilation to the contact when the breaker is close to rated capacity

Last Answer : Answer: B

An important factor in reducing D.C. motor commutator wear is _______________. A. keeping the ambient humidity as low as possible B. ensuring a very low brush current density C. establishing the copper oxide surface film D. all of the above

Description : An important factor in reducing D.C. motor commutator wear is _______________. A. keeping the ambient humidity as low as possible B. ensuring a very low brush current density C. establishing the copper oxide surface film D. all of the above

Last Answer : Answer: C

Propulsion DC motor brush pressures can be calculated by _____________. A. dividing the brush contact area by the spring pressure B. subtracting the brush contact area from the spring pressure C. dividing the spring force by the brush contact area D. subtracting the spring pressure from the brush contact area

Description : Propulsion DC motor brush pressures can be calculated by _____________. A. dividing the brush contact area by the spring pressure B. subtracting the brush contact area from the spring pressure C. ... force by the brush contact area D. subtracting the spring pressure from the brush contact area

Last Answer : Answer: C