1. The ratio of the amount of electricity in the cross section of the conductor to the time required to pass the amount of electricity refers to (a) a, three-phase short circuit b, two-phase short circuit c, two-phase ground short circuit d, single-phase short circuit a, three-phase short circuit b, two-phase short circuit c, two-phase ground short circuit d, single-phase short circuit a, three-phase short circuit b, two-phase short circuit c, two-phase ground short circuit d, single-phase short circuit a, three-phase short circuit b, two-phase short circuit c, two-phase ground short circuit d, single-phase short circuit a, knife switch b, iron shell switch c, transfer switch d, low voltage circuit breaker a, knife switch b, iron shell switch c, transfer switch d, low voltage circuit breaker a, knife switch b, iron shell switch c, transfer switch d, low voltage circuit breaker a, knife switch b, iron shell switch c, transfer switch d, low voltage circuit breaker a, porcelain plug-in fuse b, spiral fuse c, unfilled tube fuse d, with filler fuse a, porcelain plug-in fuse b, spiral fuse c, unfilled tube fuse d, with filler fuse a, porcelain plug-in fuse b, spiral fuse c, unfilled tube fuse d, with filler fuse a, porcelain plug-in fuse b, spiral fuse c, unfilled tube fuse d, with filler fuse 66. The power outage sequence is (d) Off-Grid Solar Inverter,Home Use Solar Inverter,Single Phase Off Grid Inverter,Off Grid Inverter 5Kw JIANGSU BEST ENERGY CO.,LTD , https://www.bestenergy-group.com
a, current b, voltage c, resistance d, electrical work
2. The difference between any two potentials in the electric field is (b).
a, resistance b, voltage c, current d, electrical work
3. Rated voltage: The maximum allowable working voltage that the insulating part can withstand for a long time means (c)
a, current b, voltage c, rated voltage d, electrical work
4. The work done by the current means (d)
a, current b, voltage c, resistance d, electrical work
5. The work done by the current per unit time means (d).
a, current b, voltage c, electrical work d, electric power
6. Equipment rated power The power consumed by the electrical equipment when operating at rated voltage is (b).
a, rated voltage b, rated power c, current d, electrical work
7. An alternating current with only one phase of sinusoidal alternating electromotive force is called (a)
a, single-phase AC b, single-phase current c, single-phase voltage d, single-phase resistance
8. An alternating current with a three-phase sinusoidal alternating electromotive force is called (a)
a, three-phase alternating current b, three-phase current c, three-phase voltage d, three-phase resistance
9. The meaning of red in the security color is (a)
a, prohibit / stop b, instructions must comply with the rules c, warning / attention d, prompt security status
10. The meaning of blue in the security color is (b)
a, prohibit / stop b, instructions must comply with the rules c, warning / attention d, prompt security status
11. The meaning of yellow in the safety color is (c)
a, prohibit / stop b, instructions must comply with the rules c, warning / attention d, prompt security status
12. The meaning of green in the safe color is (d)
a, prohibit / stop b, instructions must comply with the rules c, warning / attention d, prompt security status
13. Equipment that must be constantly moved during work, or that does not need to build a special foundation and often change its working place when it is installed (b)
a, hand-held electrical equipment b, mobile electrical equipment c, fixed electrical equipment d, leak detection device
14. Electrical equipment that must be manually held and moved by the mobile device body or work together is (a)
a, hand-held electrical equipment b, mobile electrical equipment c, fixed electrical equipment d, leak detection device
15. Electrical equipment installed on a special basis other than mobile and hand-held is (c)
a, hand-held electrical equipment b, mobile electrical equipment c, fixed electrical equipment d, leak detection device
16. When the leakage current in the power network reaches a dangerous value, the device that can automatically cut off the power supply is (d)
a, hand-held electrical equipment b, mobile electrical equipment c, fixed electrical equipment d, leak detection device
17. The operation of moving (moving) the installation position of the equipment under the charged state is (a)
a, live relocation b, no live relocation c, dangerous operation d, safe operation
18. Compared with general-purpose equipment, general-purpose electrical equipment for mines (abcd) have requirements for adapting to specific conditions of coal mines, and can prevent direct contact and charging of parts from the outside and prevent vertical dripping of water droplets, and creepage distance of terminal blocks and There are special regulations for air gaps.
a, medium temperature b, moisture resistance c, shell material and strength d, line device
19. Explosion-proof electrical equipment specially used for coal mine underground production according to GB3836.1-2000 standard means (d)
a, hand-held electrical equipment b, mobile electrical equipment c, leak detection device d, mine explosion-proof electrical equipment
20. When the power supply voltage is as low as the specified limit value, the relay protection device that can automatically cut off the power supply is (a)
a, under voltage release protection device b, leak detection device c, mobile electrical equipment d, grounding device
21. The total grounding and grounding conductors and grounding leads are collectively referred to as (b)
a, leak detection device b, grounding device c, under voltage release protection device d, incoming line device
22. The grounding poles that are buried separately in a centralized or single location with electrical equipment (including junction boxes that connect the power armored cables) are (a)
a, local grounding pole b, grounding resistance c, incoming line device d, leak detection device
23. In the process of transportation of electric energy from the power plant to the user, power and energy loss will inevitably occur, and the power generated corresponding to this loss is (b)
a, power load b, line loss load c, power supply load d, power load
24. In the classification of electric load, sudden interruption of power supply will result in the greatest loss and damage (a)
a, one type of load b, two types of load c, three types of load d, four types of load
25. In the power load classification, the power supply is suddenly interrupted, and the loss and harm caused by it will be minimal ( c )
a, one type of load b, two types of load c, three types of load d, four types of load
26. The purpose of which type of protection is to prevent the overhead line entering the substation from being subjected to direct lightning strikes in the near area, and to limit the overvoltage value of the lightning intruding wave input from a remote place to a lightning arrester or cable line, series reactor, etc. Smaller values ​​that are not dangerous to electrical equipment. (a)
a, substation line protection
b. Install the valve type arrester on the busbar of the substation
c. Install the valve type arrester at the neutral point of the main transformer
d. Install a valve type arrester at the terminal of the power cable directly connected to the overhead line.
27. What type of short circuit belongs to the following figure ( a )
28. What type of short circuit belongs to the following figure ( d )
29. What type of short circuit belongs to the following figure ( b )
30. What type of short circuit belongs to the following figure ( c )
31. Thundercloud directly discharges electrical equipment or power lines. When lightning current flows through these devices, an impulse voltage is generated on the impedance of the lightning current flow path (including the grounding resistance), causing an overvoltage. This overvoltage is called (a)
a, direct lightning strike voltage b, lightning strike counter overvoltage
c, inductive lightning overvoltage d, lightning intrusion wave
32. Thundercloud discharges the top of the tower of the power overhead line, or the thundercloud discharges the lightning line at the top of the power overhead linear tower. There is a high potential at the top of the tower. This high potential acts on the wire insulator of the line. If the voltage is high enough, it may cause breakdown and discharge the wire. This condition is called (b).
a, direct lightning strike voltage b, lightning strike counter overvoltage
c, inductive lightning overvoltage d, lightning intrusion wave
33. Lightning occurs not far in the vicinity of electrical equipment (such as overhead power lines). Although lightning does not directly hit the line, a large amount of bound charge opposite to the thundercloud is induced on the wire, forming (c)
a, direct lightning strike voltage b, lightning strike counter overvoltage
c, inductive lightning overvoltage d, lightning intrusion wave
34. A rapidly flowing charge in a transmission line conductor due to a direct lightning strike or an induced lightning strike is called (d)
a, direct lightning strike voltage b, lightning strike counter overvoltage
c, inductive lightning overvoltage d, lightning intrusion wave
35. The overvoltage that is generally caused by an unbalanced fault in the line no-load, single-phase grounding or three-phase system and may last for a long time is (a)
a, power frequency overvoltage b, resonant overvoltage
c, operating over voltage d, inductive lightning overvoltage
36. When the integrated impedance in the circuit is very small, a large current will occur at a low power supply voltage. This extremely large current produces a high voltage drop in the inductor and capacitor, which is (b)
a, power frequency overvoltage b, resonant overvoltage
c, operating over voltage d, inductive lightning overvoltage
37. In the power system, due to operation or accident, the operating state of the equipment changes, and the electric field and magnetic field energy on the capacitance and inductance of the related equipment are mutually converted. The mutual conversion of the electric and magnetic energy may cause the overvoltage generated by the oscillation. (c)
a, power frequency overvoltage b, resonant overvoltage
c, operating over voltage d, inductive lightning overvoltage
38. When a misoperation occurs, a strong arc can cause arc burns, which can cause redness, blistering, tissue scorching, and necrosis. This is the following type of electrical injury (a)
a, electric burn b, electric imprint c, skin metallization d, electric shock
39. The following type of electrical injury occurs at a good contact point between the human body and the charged body (b)
a, electric burn b, electric imprint c, skin metallization d, electric shock
40. The following type of electrical injury is caused by the high temperature arc causing the surrounding metal to melt, evaporate and splash into the skin surface ( c )
a, electric burn b, electric imprint c, skin metallization d, electric shock
41. Among the following current types, the current that can be felt by the human body but not damaged is (a)
a, sense current b, get rid of current c, lethal current d, detection current
42. Among the following current types, the human body can get rid of it after electric shock, and the current with pain and heart rate disorder is (b)
a, sense current b, get rid of current c, lethal current d, detection current
43. Among the following current types, the life-threatening current of the human body after being shocked is (c)
a, sense current b, get rid of current c, lethal current d, detection current
44. The human body is on the ground or other grounding conductor, and an electric shock accident in which a part of the human body touches a phase charged body is (a)
a, single-phase electric shock b, two-phase electric shock c, strid voltage electric shock d, contact voltage electric shock
45. The electric shock accidents of two human bodies touching the two-phase charged body at the same time are (b)
a, single-phase electric shock b, two-phase electric shock c, strid voltage electric shock d, contact voltage electric shock
46. ​​When the charged body has a ground fault, a fault current flows into the earth, and a current voltage drop occurs in the soil around the ground point. When a person is around the grounding point, there is a stride voltage between the two feet, and the electric shock caused by the voltage is (c)
a, single-phase electric shock b, two-phase electric shock c, strid voltage electric shock d, contact voltage electric shock
47. The electric shock caused by the contact voltage is (d)
a, single-phase electric shock b, two-phase electric shock c, strid voltage electric shock d, contact voltage electric shock
48. Under different environmental conditions, the following safety voltages specified in China are (d)
a, AC 220V b, AC 110V c, AC 55V d, AC 36V
49. Under different environmental conditions, the following safety voltages that I have specified are ( abcd )
a, AC 42V b, AC 36V c, AC 12V d, AC 6V
50. DC safety voltage upper limit is (c)
a, 220V b, 110V c, 72V d, 80V
51. What type of low voltage switch is shown in the figure below ( a )
52. What type of low voltage switch is shown in the figure below ( b )
53. What type of low voltage switch is included in the figure below ( c )
54. What type of low voltage switch is shown in the figure below ( d )
55. The following fuses belong to the low-voltage fuse: (abcd)
a, porcelain plug-in fuse b, spiral fuse c, unfilled tube fuse d, with filler fuse The fuse below is the kind of low-voltage fuse (a)
57. The fuse below is the kind of low voltage fuse (b)
58. The fuse below is the kind of low voltage fuse (c)
59. The fuse below is the kind of low voltage fuse (d)
60. The pointer multimeter operation technique is: (c)
1. Carefully check the position of the test leads before measurement
2. According to the measurement object, turn the transfer switch to the corresponding gear position.
3. When reading, read the data according to the measured object at the corresponding scale.
4, measurement
a, 1324 b, 1423 c, 1234 d, 3241
61. Grounding resistance measuring instrument The specific steps of measuring the grounding resistance of the line are: (c)
1. Disconnect the grounding mains from the grounding body or disconnect the grounding points of all the grounding lines on the grounding mains.
2. Install a temporary grounding wire at the disconnected ground wire.
3. Insert the two measuring ground rods into the ground 20m away from the grounding body and 40m away. Both should be inserted vertically into the depth of the ground for 400mm.
4. Place the grounding resistance meter in a flat place near the grounding body and then wire it.
5. After the measurement, remove the insulation resistance meter to measure the wiring, connect the connection point between the grounding trunk and the grounding body, and remove the temporary grounding wire.
a, 13245 b, 23451 c, 12345 d, 52314
62. ETCR2000 clamp type grounding resistance meter operation steps are (c)
1. After pressing the POWER button, the meter is energized and the clamp is in self-test state; at this time, the natural static state of the clamp should be maintained. The clamp should not be turned over. The clamp should not apply any external force in any direction, otherwise the test accuracy will be affected.
2. After the power-on self-test status is over, the night crystal display “OL†can be tested. If “E†is displayed, the self-test is incorrect and cannot enter the test state.
3. Test once with a random test loop. The value displayed at this time should be consistent with the standard value of the test loop.
4, the horizontal hand holding the pliers table, open the jaws, put the tested wire, flat iron, etc. into the jaws, the jaws closed, observe the liquid crystal display.
5. The data recorder records the location and data, and always pays attention to the top of the building to prevent foreign objects from falling and injuring people.
6. After the test is finished, gently open the jaws, remove the clamp, and press the POWER button.
a, 123465 b, 154236 c, 123456 d, 546321
64. The use of DC single-arm bridge is (c)
1. Open the galvanometer lock first, then adjust the zero adjuster so that the pointer is at zero.
2. Connect the measured resistance Rx to the two terminals labeled “Rxâ€. According to the estimated value of the measured resistance, put the measurement magnification of the bridge to the appropriate position and adjust the variable resistance to a certain position. The right place.
3. When measuring, first press the power button “Bâ€, then press the galvanometer button “G†to adjust the variable resistance according to the direction of the galvanometer pointer. If the galvanometer pointer is deflected to “+â€, it indicates that it should be added. Large comparator arm resistance; if the pointer is deflected toward "-", the comparator arm resistance should be reduced. Repeat the adjustment of the arm resistance until the galvanometer is zero and the bridge is fully balanced.
4. At the end of the measurement, the galvanometer button “G†should be released before the power button “B†can be released. If the power button "B" is released first, when measuring the resistance with a large inductance, the self-induced electromotive force will be generated due to the disconnection of the power supply. This electromotive force acts on the galvanometer circuit, causing the galvanometer pointer to collide and damage, even Burn out the coil of the galvanometer. The galvanometer pointer should be locked after the bridge is used.
a, 1324 b, 1432 c, 1234 d, 4321
65. The normal operation of the test for fixed equipment is: (a)
1. When conducting test work on a normal operating fixture, you must contact the driver on duty and explain the driver's precautions during the test. If there is any change, ask the driver to explain clearly.
2. When testing on a normal operating device, the device must be taken out of the normal operating system. The test can only be carried out after the standby device is in normal operation.
3. When testing without backup equipment, before the test, measures must be taken on the equipment system to make the equipment meet the normal operation requirements, in case there is a critical situation after the power failure and shutdown during the test.
4. When testing in an abnormal state, there must be safety technical measures, and the test can only be carried out after approval by the technical person in charge.
5. Mine hoist winch dynamic test After emergency braking, the wire rope must be inspected. When the wire rope meets the requirements, the winch can be put into normal operation.
6. When testing the mine pump, the pump gate should be closed before the pump starts, so that the motor starts in the light load state, then gradually open the gate to increase the motor load.
a, 123456 b, 123654 c, 256314 d, 654321
1. The power failure operation of the transformer (distribution) should be carried out by two people. One of them is monitored and operated by one person. According to the content and sequence of the operation of the switch operation, the simulation operation is first performed on the operation simulation board, and the switch device can be operated without any error. .
2. The switch on both sides of the transformer, the power failure operation sequence is to stop the load side and then stop the power supply side; first stop the low voltage, then stop the high voltage.
3. When there is a capacitor device, the capacitor group switch should be stopped first, and then each outlet switch should be stopped.
4. When operating the switchgear, stop the circuit breaker first, then stop the isolating switch. When stopping the circuit breaker, stop the circuit breaker first, then stop the total circuit breaker; when stopping the isolation switch, pull the load side first and then pull the power side.
a, 3214 b, 4321 c, 2314 d, 1234
67. The voltage is below 110kV, the voltage is lower, the transmission power is smaller, the transmission distance is shorter, and the main power is supplied to the local load, which is called local network. With the development of the national economy, the voltage level has gradually reached 220kV. Such grids are: (a)
a, local network b, regional network c, city network d, rural network
68. The voltage of 110kV and above, the voltage is higher, the transmission power is large, the transmission distance is long, and the main power is supplied to the large regional substation, called (b)
a, local network b, regional network c, city network d, rural network
69. The main part of the transformer includes (c).
a, a closed core b, two coils (often called windings)
c, a closed core and two coils d, winding
70. The power transformer can be divided into (b) according to the cooling medium.
a, oil immersed b, oil immersed and dry type c, dry d, special transformer
71. The ratio of the primary and secondary voltages of the single-phase transformer to the turns ratio of the primary and secondary windings is (a).
a, proportional b, inverse ratio c, 1:1 relationship d, uncertain
72. The ratio of the primary and secondary currents of the single-phase transformer to the turns ratio of the primary and secondary windings is (b).
a, proportional b, inverse ratio c, 1:1 relationship d, uncertain
73. The iron core of the power transformer is composed of (b) two parts.
a, core column b, core column and iron yoke c, iron yoke d, winding
74. The structure of the transformer core is generally divided into two categories: (d).
a, heart b, shell c, winding d, heart and shell
75. The power transformer adjusts the voltage by setting a tap on one of the side windings and changing (d) to achieve a stepwise adjustment of the voltage ratio.
a, current b, voltage c, winding d, number of turns of the winding
76. The temperature of each component is different when the transformer is running, and (c) the temperature is the highest.
a, core b, transformer oil c, winding d, outer casing
77. In order to facilitate monitoring the temperature of various components of the transformer during operation, (a) is specified as the allowable temperature.
a, upper oil temperature b, core temperature c, winding temperature d, case temperature
78. Parallel operation of the transformer is to connect the primary side and secondary side windings of two or more transformers to (a) and supply power to the load.
a, common bus b, two coils c, neutral point d, winding
79. The isolating switch has no special structure (c), and it is not allowed to use it to carry out the pulling or closing operation.
a, core b, neutral point c, arc extinguishing device d, winding
80. The operation sequence when the isolating switch and the circuit breaker are closed is (b):
a, first cut off the load circuit with a circuit breaker, then disconnect the isolating switch
b. Close the isolation switch first, then connect the load circuit with a circuit breaker.
c. At the same time as the isolating switch is closed, the load circuit is connected by a circuit breaker.
d, the above are all wrong
81. The operation sequence when the isolating switch and the circuit breaker are opened is (a):
a, first cut off the load circuit with a circuit breaker, then disconnect the isolating switch
b. Close the isolation switch first, then connect the load circuit with a circuit breaker.
c. At the same time as the isolating switch is closed, the load circuit is connected by a circuit breaker.
d, the above are all wrong
82. Vacuum circuit breaker refers to (c) a circuit breaker that divides and combines circuits in a high vacuum.
a, isolation switch b, core c, contact d, winding
83. The high voltage circuit breaker is a special electrical appliance for the high voltage circuit under normal or fault conditions.
a, turn on b, turn on or off c, turn off d, all of the above are wrong
84. The main part of the vacuum circuit breaker is a vacuum interrupter, which is composed of (d) and other parts.
a, moving contact and static contact b, static contact and shield
c, moving contact, static contact, shield d, moving contact, static contact, shield, insulating shell
85. Sulfur hexafluoride circuit breaker is a high voltage circuit breaker that uses (d) gas as insulation and arc extinguishing medium.
a, SF2 b, SF3 c, SF5 d, SF6
86. A power device consisting of multiple high-voltage switchgears installed in a power plant, substation or power distribution station is called (a).
a, complete power distribution device b, control device c, power distribution device d, substation
87. Insufficient reactive power will cause (c), thus damaging the electrical equipment, which will seriously cause the grid to collapse, causing the system to collapse and causing large-scale power outages.
a, the system voltage rises b, the system power decreases
c, system voltage decreases d, system current decreases
88. The direct function of the phase shifting capacitor is to increase the line (d) in parallel on the line.
a, current size b, voltage size c, power level d, power factor
89. The ambient temperature of the capacitor should not exceed (c).
a, 20 ° C b, 30 ° C c, 40 ° C d, 50 ° C
90. The relative humidity of the air around the environment where the capacitor is located should not be greater than (d).
a, 50% b, 60% c, 70% d, 80%
91. The altitude of the environment where the capacitor is located should not exceed (b).
a, 900m b, 1000m c, 1100m d, 1200m
92. High-voltage capacitors with a total oil quantity (a) or higher shall be installed in a separate explosion-proof room.
a, 300kg b, 400kg c, 500kg d, 600kg
93, high voltage capacitors can use (b) as the discharge load;
a, the low voltage winding b of the voltage transformer, the high voltage winding of the voltage transformer
c, lighting equipment d, electric motor
94. The internal three-phase capacitor is (c) when the rated voltage of the delta connection capacitor matches the line voltage.
a, series b, parallel c, delta connection d, star connection
95. The internal three-phase capacitor is (d) when the rated voltage of the delta connection capacitor matches the line phase voltage.
a, series b, parallel c, delta connection d, star connection
96. The current in the capacitor operation should not exceed (c) times the rated current of the capacitor for a long time.
a, 1.1 b, 1.2 c, 1.3 d, 1.4
97. Under normal circumstances, the parallel capacitor should be put into or out according to the height of the line (d) and the level of the voltage.
a, current size b, voltage size c, power level d, power factor
98. When the power factor is lower than (a) and the voltage is low, the capacitor bank should be put into operation.
a, 0.9 b, 0.8 c, 0.7 d, 0.6
99. When the power factor approaches 1 and there is a leading trend, (b) should exit the capacitor bank.
a, the current is high b, the voltage is high c, the current is low d, the voltage is low
100. When the total capacity of the high voltage capacitor bank does not exceed 100kvar, (b) is available.
a, load switch protection and control
b, fall fuse protection and control
c, vacuum circuit breaker or other circuit breaker protection and control
d, AC contactor, knife switch, fuse or knife fuse switch protection and control
101. When the total capacity is 100~300kvar, (a) should be adopted.
a, load switch protection and control
b, fall fuse protection and control
c, vacuum circuit breaker or other circuit breaker protection and control
d, AC contactor, knife switch, fuse or knife fuse switch protection and control
102. When the total capacity is above 300kvar, (c) should be used.
a, load switch protection and control
b, fall fuse protection and control
c, vacuum circuit breaker or other circuit breaker protection and control
d, AC contactor, knife switch, fuse or knife fuse switch protection and control
103. When the total capacity of the low-voltage capacitor bank does not exceed 100kvar, (d) is available.
a, load switch protection and control
b, fall fuse protection and control
c, vacuum circuit breaker or other circuit breaker protection and control
d, AC contactor, knife switch, fuse or knife fuse switch protection and control
104. When the total capacity is above 100kvar, (d) should be used.
a, load switch protection and control
b, fall fuse protection and control
c, vacuum circuit breaker or other circuit breaker protection and control
d, low voltage circuit breaker protection and control
105. The 10kV power capacitor without fuse inside should be protected by the fuse of the stage. The fuse current should be selected according to the rated current of the capacitor (c).
a, 0.5~1 times b, 1.0~1.5 times c, 1.5~2 times d, 2~2.5 times
106. Under normal circumstances, when the whole station is powered off, it should be (a).
a, first open the switch of the capacitor, then pull open the switch of each line
b. First close the switch of each line, then close the switch of the capacitor line
c. Close the switch of each line and close the switch of the capacitor line.
d, the above are all wrong
107. Under normal circumstances, when the whole station resumes power transmission, it should be (b).
a, first open the switch of the capacitor, then pull open the switch of each line
b. First close the switch of each line, then close the switch of the capacitor line
c. Close the switch of each line and close the switch of the capacitor line.
d, the above are all wrong
108. In order to check and repair, after the capacitor is disconnected from the power supply, the worker must use (b) for manual discharge before the worker approaches, regardless of whether the capacitor is equipped with a discharge device.
a, lighting equipment b, portable special discharge load
c, motor d, reactor
109. The static dynamic reactive power compensation device is abbreviated as (d).
a, SUC b, SVB c, SUB d, SVC
110, SVC working principle description The