When a fire breaks out in electrical equipment, what kinds of equipment can be put out by electricity? Answer: 12 1 1 carbon dioxide and carbon tetrachloride dry powder (the two answers are correct) 2. According to the frequency of electric shock accidents, which months of the year are the most concentrated months of electric shock accidents? A: What is the maximum voltage in safe voltage from June to September 3rd? Answer: 42 volts. 4. What is a safe DC current through people? Answer: 50mA 5. What is the safe AC current through human body? Answer: 10A6. What should I do first to get an electric shock? And then do what right away? Answer: electric shock rescue; Artificial respiration. 7. How many kinds of protective devices are there to prevent direct lightning in our factory? Answer: lightning rod; Lightning protection network; Lightning eliminator. 8. When the conductor is grounded, the closer the human body is to the grounding point, the higher the step voltage, and the farther the distance, the lower the step voltage. Generally speaking, the step voltage can be regarded as zero. A:/kloc-within 0/0 meter b: over 20 meters c: over 30 meters A: B 9. Low-voltage test pens are generally suitable for AC and DC voltages below () V A: 220b: 380c: 500 A: C 10. The lighting facilities on the construction site should take measures to prevent electric shock (). A: Wear insulating gloves B: Cut off the power C: Stand on the insulating board A: B 1 1. Whether the person who gets an electric shock can be rescued depends on () A: How to get an electric shock B: The magnitude of human body resistance C: The voltage of electric shock D: Can you leave the power supply as soon as possible for emergency rescue A: D 12: What is the main purpose of eliminating static electricity on the pipeline? Answer: Grounding 13, what is safe voltage? Answer: Under various environmental conditions, when the human body comes into contact with a charged body with a certain voltage, its tissues (such as skin, heart, viscera, respiratory organs and nervous system, etc. ) will not be damaged, and this voltage is called safe voltage. 14. What are the main factors that affect the harm of current to human body? A: The main factors are: current, human body resistance, duration of power-on, current frequency, voltage, current path and human body condition. 15, start the motor after it stops running. How many times does the hot state allow hot start? How many times is it allowed to start continuously in cold state? A: 1 time; 16, 2~3 times that of electric machinery and equipment used for construction, what protective measures should be taken? Answer: Protective grounding must be adopted and grounding must be repeated at the same time. 17, what are the two parts of electrical safety measures? A: Organizational measures and technical measures. 18, what are the main ways to get rid of low-voltage power supply? Answer: (1) cut off the power supply; (2) cut off the power cord; (3) Pull down the power cord; (4) Pull away the person who gets an electric shock; (5) Take corresponding rescue measures. When taking the above measures, pay attention to the use of insulation tools that meet the corresponding voltage level. 19, what is the sequence of disconnectors during power transmission? Answer: Connect the bus side first and then the line side. 20. Can the switch of distribution box switch be opened with load? A: No.21. What kind of power tools must be used when using hand-held or mobile power tools in places with explosion and fire danger? A: There are explosion-proof measures. 22. How many volts of safe voltage should be used when using portable appliances or lighting lamps in wet workplaces or metal containers? Answer: 12V. 23, motor test run, can you move together and immediately press the stop button? Why? Answer: No, the starting current is 6~7 times of the rated current. Stopping immediately will burn out the switch. 24. Most motors in our factory are explosion-proof motors. What is the explosion-proof grade? Answer: dIIBT4 25. Is the explosion-proof motor in our factory waterproof? Answer: No.26, when the tool load does not reach the rated load, the motor will not be overloaded, will it? Why? A: No, medium change, pump failure and motor failure will all lead to overload. 27, why not do fire tickets, temporary electricity tickets are not allowed to pick up temporary electricity? Answer: Temporary power consumption is the power consumption that generates sparks, which easily leads to electric shock safety accidents and fire and explosion accidents. You must apply for fire tickets and temporary electricity tickets, and take certain safety measures at the construction site before you can receive temporary electricity. 28, indoor lighting circuit electrical equipment, the total capacity of each circuit should not exceed how many kW? ( 1 ) 1 ; ( 2 ) 2 ; ( 3 ) 3 。 A: (2) 29. The capacity of the socket should be adapted to the power load. How many electrical appliances are allowed to be connected to each socket? Answer: 1 30, when the relative humidity in the workplace is more than 75%, the working environment is easy to get an electric shock: (1) dangerous; (2) Particularly dangerous; (3) General answer: (1) 3 1. In order to prevent accidents caused by electrostatic sparks, all equipment metal pipelines and non-conductive materials pipelines used for processing, storing and conveying various combustible gases, liquids and powders must have (1) sufficient resistance; (2) It has a sufficiently small resistance; (3) Answer of grounding gas: (3) 32. The power cord and wires of electric tools should be yellow-green double-color wires. (1) phase; (2) working zero line; ③ Protective grounding. Answer: (3) 33. The most effective measure to ensure the personal safety of electrical maintenance personnel is. (1) hang a signboard; (2) placing obstacles; (3) Maintenance equipment grounding and short circuit. Answer: (3) 34. From a safety point of view, there must be an obvious. (1) signboard: (2) grounding position; (3) the disconnection point. Answer: (3) 35 The confirmation that the equipment or line has no electricity shall be subject to the instruction manual. (1) voltmeter; (2) electroscope; (3) Disconnect the signal. A: (2) 36. It is forbidden to get close to various electrical equipment such as distribution boards (boxes), switches and transformers. (1) Set fire extinguishers; (2) setting up fences; 3) Stack inflammable, explosive, damp and other items that affect the operation. Answer: (3) 37. In ordinary houses and offices, if the main purpose is to prevent electric shock, the leakage protection switch with leakage action current of mA should be selected. ( 1 ) 6 ; ( 2 ) 15 ; ( 3 ) 30 。 Answer: (3) 38. The power cord of portable electric tools and its switch board (box) must be used. 1) double-layer plastic copper-core insulated conductor; (2) Double-stranded copper-core plastic cord; (3) Copper-core rubber insulated sheath or copper-core PVC insulated sheath cord. Answer: (3) 39. In general, the power cord length of portable electric tools should not exceed 100 m. (1) 2; ( 2 ) 3 ; ( 3 ) 4 。 A: (2) 40. For hand-held electric tools that have not been used for a long time, the insulation resistance must be measured before use. It is required that the insulation resistance between the live parts of Class I hand-held power tools and the shell shall not be lower than mω. ( 1 ) 2 ; ( 2 ) 0.5 ; ( 3 ) 1 。 Answer; (2) 4 1, what is a short circuit? Answer: Short circuit refers to the phenomenon that the phase lines collide with each other, and the phase lines collide with the neutral line or the ground in the electrical circuit without passing through the load or the resistance is very small, resulting in a substantial increase in the current in the electrical circuit. 42. What are the hazards of short circuit? Answer: Short-circuit current will cause short circuit and even the whole circuit to overheat, so that the insulation layer of the conductor will burn and ignite the combustible materials in the surrounding buildings. 43, mobile fans, lighting and mobile electric welding machine and other electrical equipment, should be under what circumstances? A: Cut off the power supply. 44, any electrical equipment in the absence of electricity, all want to think, can't blindly touch. A: There is electricity. 45, 1kW iodine tungsten lamp lamp surface temperature can reach how many degrees? A: 500~800 degrees Celsius. 46. Why do incandescent lamps break easily when they are turned on? Answer: The filament is cold and the resistance is small. When electrified, the current is large (about 10 times), and it is easy to break after a long time. 47. Both ends of the fluorescent lamp are red and not bright. Can it run continuously? Why? Answer: No, at this time, the current is greater than the rated current, which will lead to (1) filament aging and damage quickly; (2) If the ballast temperature is too high, it will cause a fire. 48. Which is more harmful to people, alternating current or direct current with the same voltage? A: alternating current. Especially 50-60 Hz alternating current. 49, electrical equipment on fire, what is the first measure that must be taken? A: There is a power outage. 50, in the process of production, temporary maintenance device shall not be near the cable trench, why? Answer: In case of deflagration caused by combustible gas in the ditch. 5 1 In case of electrical equipment operation, operators should take emergency measures to start the standby unit, stop using the abnormal unit, and notify professionals to check and handle it. Answer: (1) The load current suddenly exceeds the specified value or misrecognizes the phase operation state; (2) the motor or switch suddenly appears high temperature or smoke; (3) The motor or other equipment rubs due to loose parts, making noise or sparks; (4) Serious mechanical load failure or endangering electrical safety.