1.The leakage protector cannot protect the two-phase electric shock, nor can it protect the short circuit between the phases. （√
2.The voltage tester is the main tool for low-voltage electrical testing, which is used for the detection of 500V and 1000V voltages. （×
3.Generally, for low-voltage equipment and circuits, the insulation resistance should not be less than 05m, the lighting line should not be less than 025 mω。（
4.In the grounding grid, when the phase wire hits the shell fault, if the human body touches the shell of the equipment, an electric shock accident will still occur. （√
5.When the single-head knife switch is installed, the static contact is placed on it and the power supply is connectedThe moving contact is placed underneath to receive the load. （√
6.When accessing the knife switch, you can ensure safety by simply pulling the knife switch open. （×
7.Small-capacity AC contactors mostly use the method of arc elongation to extinguish the arc. （√
8.For lines with multiple motor loads, the rated fusing current of the fuse should be greater than or equal to 15~2.5 times the sum of the rated currents of each motor. （×
9.The capacitor current in the row exceeds 13 times, should be out of operation. （√
10.After the melt is blown off, the cause of the failure can be found by fusing the melt, but the specifications of the melt cannot be easily changed. （×
11.The motor housing must have reliable protective grounding or zero connection. （√
12.When the power supply is out of phase, the motor continues to run, but the current increases. （√
13.High pile tie wires are used to cross highways and channels, etc. （√
14.The wire is in the same plane, if there is a porcelain bead or porcelain bottle when bending, it must be installed on the outside of the zigzag corner of the wire. （×
15.Non-armoured cables are not allowed to be buried directly. （√
16.The surface brightness of a normal bulb is less than that of a fluorescent lamp. （×
17.The number of lamps and lanterns in each lighting branch should not exceed 10. （×
18.The outer bridge wiring is suitable for situations where it is necessary to cut off or put into the transformer frequently. （√
19.In order to avoid the influence of short-circuit current, the current transformer must be equipped with a fuse. （×
20.Verbal appointments can be made for power outage and power transmission operations. （×
21.When the transformer is in a power outage, the load side is stopped first, and then the power supply side is stopped, and the opposite is true when the power is transmitted. （√
22.* Hazardous places, according to the state of the substance, are divided into two categories: gas hazardous places and dust hazardous places. （√
23.*Hazardous locations do not have special requirements for grounding (zeroing). （×
24.The down lead of the lightning protection device should meet the requirements of mechanical strength, corrosion resistance and thermal stability. （√
25.The down conductor should be treated with anti-corrosion, and aluminum wire or copper wire should be used as the down conductor. More than 30% of the down conductor section should be replaced. （×
26.In order to prevent high voltages generated by electrostatic induction, metal pipes in the building, steel bars of metal equipment structures, etc., should be grounded, and the grounding devices can be shared with other grounding devices. （√
27.The best shielding is a sealed metal shielded case, which should be well grounded. （√
28.As the wavelength of electromagnetic waves shortens, the damage to the human body increases. （√
29.When measuring DC high current, the method of meter series shunt is generally used to expand the range. （×
30.When measuring resistance with a multimeter, it must be carried out without a power outage, while measuring resistance with a shake meter does not have to be blackout. （×
31.The internal resistance of the micro-ampere meter should not be directly measured with the resistance of the multimeter, but the internal resistance of the galvanometer and standard battery can be directly measured. （×
32.Electrical safety inspections are generally conducted once a quarter. （√
33.Electrical safety inspections are necessary to prevent accidents before they occur. （×
34.The rubber cover knife switch cannot directly control the motor. （×
35.When the power load is less than 60A, the spiral fuse is generally selected instead of the tubular fuse. （√
36.When using an RL spiral fuse, the center contact of the base is connected to the load, and the spiral is partially connected to the power supply. （×
37.The capacitor voltage in the row should not exceed 1 of the rated value2 times. （×
38.For long-term operation of the motor, the bearing should be inspected and changed once every two years. （×
39.After the overhaul, the insulation resistance of the high-voltage motor should be greater than 0 per kilovolt voltage5 mω。（
40.The copper wire has the smallest resistance and poor electrical conductivity. （
41.Porcelain column and porcelain vase wiring are not suitable for indoor and outdoor wiring. （×
42.Steel pipe wiring is generally suitable for indoor and outdoor places, but it is not suitable for places with serious corrosion of steel pipes. （√
43.Accident lighting fixtures should be powered by a separate line. （√
44.The voltage of the general lighting power supply to the ground should not be greater than 250V. （√
45.The pull wire switch is generally 2m 3m from the ground. （√
46.The high-voltage fuse has a time-limited characteristic. （×
47.The valve-type resistance plate of a valve-type arrester is a non-linear resistor. （√
48.When the bus is in power failure operation, the voltage transformer should be powered off first, and the voltage transformer should be closed first when power is transmitted. （×
49.In electrical test work, it must be carried out by two people. （√
50. "Normal condition refers to the normal start, stop, normal operation, and maintenance of the equipment. An abnormal condition is a situation in which a device failure is possible"。（×
51.To maintain the normal operation of explosion-proof electrical equipment, it mainly includes keeping the voltage and current parameters not exceeding the allowable value, and the electrical equipment and lines have sufficient insulation capacity. （×
52.1. on the ground7m to 0 below ground levelA section of 3m down conductor should be added with a protection tube, and when a metal protection tube is used, it should be connected with the down conductor to reduce the reactance when passing through the lightning current. （√
53. 53；The main measures to prevent direct lightning strikes are to install lightning rods, lightning cables, lightning arresters, and lightning belts. （×
54.The internal overvoltage of the substation includes the operating overvoltage, power frequency overvoltage and lightning overvoltage. （×
55.Sex is most sensitive to electromagnetic radiation. （×
56.The greater the strength of the electromagnetic field, the less harmful it will be to the human body. （×
57.The "*" end of the electric power meter current coil must be connected to the power supply and the other end to the load. （√
58.The highest and lowest settings are not allowed when testing transistor components with a multimeter ohm. （√
59.In order to ensure safety, hand-held power tools should be selected as much as possible. （×
60.Hand-held power tools should be managed by a special person and checked for safety and reliability frequently. Classes and classes should be used as much as possible. （√
61.The secondary winding of the voltage transformer is not allowed to open the circuit, and the secondary winding of the current transformer is not allowed to be short-circuited.
62.DC ammeters can be used in AC circuits. （×
63.Clamp-on ammeters can be made to measure both AC and DC currents. （×
64.Use a multimeter to measure the resistance, and zero the pointer every time you change the ohm. （√
65.The greater the internal resistance of the ammeter where the current is measured, the better. （×
66.Whether it is measuring direct current or alternating current, the neon lamp emitting of the electroscope is the same. （×
67.The protective terminal of the soldering iron can be wired or unwired. （×
68.When installing the temporary grounding wire, the three-phase line end should be installed first, and then the grounding terminal should be installedOn the contrary, remove the grounding terminal first, and then disassemble the three-phase line end. （×
69.Welding machine.
The length of the primary and secondary wiring should not exceed 20m. （
70.Both the AC ammeter and the voltmeter indicate valid values. （√
71.Insulated boots can also be used as acid, alkali and oil resistant boots. （×
72.The safe ampacities of the conductor should have different values at different ambient temperatures, and the higher the ambient temperature, the greater the safe ampacity. （×
73.When the steel-core aluminum stranded wire passes through the alternating current, due to the skin effect of the alternating current, the current actually only flows through the aluminum wire, so its effective cross-sectional area is only part of the area of the aluminum wire. （√
74.Bare wires must be laid indoors at a height of 3More than 5m, less than 35m is not allowed to be erected. （×
75.The wires are laid in the ceiling or ceiling, and can be protected without pipes. （×
76.All pipe-through lines must have no more than 1 in-pipe connection. （×
77.The cable core is sometimes pressed into round, semicircular, fan-shaped and other shapes, which is to reduce the cable size and save raw materials. （×
78.When the power failure of the substation, pull the isolation switch first, and then cut off the circuit breaker. （×
79.During the operation of the high-voltage disconnector, if it is found that the surface of the insulator is seriously discharged or the insulator is broken, the high-voltage disconnector should be immediately disconnected and withdrawn from operation. （×
80.The high-voltage load switch has an arc extinguishing device that can disconnect the short-circuit current. （×
81.The degree of risk of electric shock depends entirely on the amount of electric current passing through the body. （×
82.For experienced electricians, it is not necessary to use a voltage tester to test after a power outage. （×
83.After using the 36V safety voltage, it is guaranteed that there will never be an electric shock accident again. （×
84.If the installation of low-voltage temporary lighting is very reliable, it can also use the "one line, one place" power supply method. （×
85.Rubber shoes worn on rainy days can also be used as insulated shoes when performing electrical work. （×
86.The specific provisions in the electrical safety regulations should be flexibly adjusted according to the specific situation in practice. （×
87.In the factory with flammable and explosive hazards, it is forbidden to use aluminum core insulated wire wiring. （√
88.When using a 1 1 safety isolation transformer, its secondary end must be reliably grounded. （×
89.Usually, after the shunt capacitor bank is cut off the circuit, it discharges itself through the voltage transformer or discharge bulb, so the substation does not need to be manually discharged after the power failure and can be repaired. （×
90.The leakage protector cannot protect the two-phase electric shock, nor can it protect the short circuit between the phases. （√
91.The primary current of the current transformer depends on the secondary current, and the larger the secondary current, the larger the primary current. （×
92.Generally, the knife switch cannot cut off the fault current, nor can it withstand the electrodynamic and thermal effects caused by the fault current. （×
93.Motors that are frequently forward, reversed and frequently started are suitable for protection by thermal relays. （×
94.The voltage tester is the main tool for low-voltage electrical testing, which is used for the detection of 500V and 1000V voltages. （×
95.Lighting fixtures in flammable and explosive places should be used closed or explosion-proof lamps, and waterproof and dustproof lamps should be used in dusty, humid and corrosive gas places. （√
96.Lighting switches in dusty, humid places or outdoor places should be made of porcelain waterproof cable switches. （√
97.Generally, for low-voltage equipment and circuits, the insulation resistance should not be less than 05m, the lighting line should not be less than 022mω。（
98.For lines with multiple motor loads, the rated fusing current of the fuse should be greater than or equal to 15~2.5 times the sum of the rated currents of each motor. （×
99.When using an RL spiral fuse, the center contact of the base is connected to the load, and the spiral is partially connected to the power supply. （×
100.The rated capacity of a transformer refers to the apparent power output of the transformer. （√