Common sense of on-site electricity safety inspection 1. What are the main contents of on-site electricity safety inspection?
I. External protection
1. 1 Below the external high-voltage line, there are no living facilities, work sheds, stacked materials and construction work areas.
1.2 The outer edge of the crane or hanging object shall keep a safe operating distance from the project under construction (scaffolding) and external overhead lines. (Voltage level, distance)
1.3 If the safe operating distance is not reached, there should be a protection scheme, and a wooden scaffold should be erected. The facade should be protected with thermal insulation materials, and the top should be covered with a scaffold with a thickness of 5cm.
Second, the distribution line.
2. 1 overhead conductors, poles and cross arms meet the specifications and design requirements, and the distance from the ground: construction site > 4m, expressway > 6m.
2.2 The laying depth of directly buried cables meets the design requirements, and crossing the road and wearing pipes are adopted for protection from 0.2m underground to 2m on the ground.
2.3 when laying overhead, it shall be fixed with insulators, and the outdoor height shall be >; 2.5m, indoor height >1.8m.
2.4 Use five-core cable as required.
2.5 indoor wiring should be laid through pipes or connected with insulators, with the height above the ground >; 2.5m, neatly arranged.
Third, the way of protection.
3. 1 Adopt TN-S system. Working grounding and repeated grounding resistance meet the requirements, and PE line and N line shall not be mixed separately.
3.2 Equipment components with a height of > 32m shall be grounded by lightning protection and repeatedly grounded, and the resistance shall meet the requirements.
Fourth, the distribution box
4. 1 meets the secondary protection requirements of three-level distribution.
4.2 There are main isolating switch, main air switch and shunt air switch in the distribution box.
4.3 The switch box shall be equipped with isolating switch, 30mA leakage switch, and 15 mA in damp and other special places, so as to make one switch leak one box at a time.
4.4 Equipment larger than 5.5KW shall be controlled by contactors.
4.5 The distribution box layout meets the requirements, the road is unobstructed, and there is enough space for two people to operate, and the height is1.3-1.5m..
4.6 The electrical appliances in the cabinet are in good condition and reliable, and the loop identification is clear. The terminal board is used for wiring and supports the chicken feet connector.
4.7 The box has doors and locks and rainproof measures.
Verb (abbreviation of verb) on-site lighting
5. 1 Lighting has a separate switch box and leakage switch.
5.2 The metal shell of lamps and lanterns should be connected with zero protection, and lamps and lanterns should keep a safe distance from the ground, flammable top surface and wires.
5.3 The conductor has no skin aging phenomenon, and it shall be fixed with insulators or protected by wearing pipes.
5.4 Use safe voltage as required.
2. What specific contents should be checked for temporary electricity consumption on the construction site?
1. Whether the rainproof and smash-proof facilities of the auxiliary box are perfect.
2. The selection of leakage protectors for secondary box, tertiary box and switch box is reasonable (leakage current and leakage action time).
3, scaffolding, tower crane, etc. Whether there is lightning protection device.
4. Whether the grounding resistance values such as working grounding and lightning protection grounding are qualified.
5. Whether the welding machine has a switch box and whether the AC welding machine is equipped with a special leakage protector for the welding machine. The wiring length of the primary side of the welder is not more than 5m, and the wiring length of the secondary side is not more than 30m. There is a special grounding wire, and steel bars shall not be used as grounding wires.
6. Whether the workers' dormitory is privately connected and whether low-voltage lighting is used for lighting.
7. On-site machines and tools must ensure one brake, one leakage and one insurance. Cables must be three-core or five-core cables, and twisted pairs are not allowed. All lines shall not be laid on the floor, and there must be reliable insulation protection with the overhead laying of existing metal objects.
8. There are not less than two repeated grounding points in the whole temporary distribution system.
A lot. I'll talk for a while.
3. Those should be paid attention to when using electricity safely on the construction site.
Attention should be paid to the safe use of electricity in the construction site:
1. Check and maintain all distribution boxes and switch boxes on the construction site once a month. Maintenance and repair personnel must be professional electricians. When working, you must wear insulating articles and use electrical insulating tools.
2. When inspecting and repairing the distribution box and switch box, the corresponding power switch at the next higher level must be switched off, and a power-off sign should be hung. It is forbidden to work with electricity.
3, the disk in the distribution box should indicate the name and purpose of each circuit, and make a shunt mark.
4, the total distribution box door should be equipped with a lock, distribution box and switch box should appoint someone who's in charge. When the construction site stops working for more than 1 hour, the power switch box should be locked.
5, all kinds of electrical boxes are not allowed to put any sundry, and should be kept clean. No other temporary electrical equipment shall be hung in the box.
6, all kinds of electrical box fuse melt replacement, it is forbidden to use the melt does not conform to the specifications instead.
Extended data
Operators and maintenance personnel of electrical equipment on the construction site must meet the following requirements:
A, the construction and maintenance of temporary electricity on the construction site must be completed by a trained professional electrician who has obtained a license, and junior electricians are not allowed to carry out intermediate or advanced operations.
B, all kinds of electricity personnel should do:
First, master the basic knowledge of safe electricity use and the performance of the equipment used.
B, before using the equipment, you must wear and equip the corresponding labor protection articles according to the regulations; And check whether the electrical devices and protection facilities are in good condition. It is forbidden to operate the equipment "with illness".
C, stop using the equipment must switch power, lock the switch box;
D, responsible for protecting the load line of the equipment used, protecting the zero line and the switch box, and solving problems in time when found.
E. When handling or moving electrical equipment, an electrician must cut off the power supply and properly handle it.
Sogou Encyclopedia-Temporary Power Consumption on Construction Site
4. Common sense of safe electricity use
1, the power cord and electrical equipment must be well insulated, and the live parts such as lamp holders, sockets and switches shall not be exposed to prevent electric shock.
2, don't pull the wire, to prevent electric shock or fire.
3, don't stand on the wet ground to move charged objects or try to clean charged household appliances with a wet rag to prevent electric shock.
4, fuse selection should be reasonable, avoid using copper wire, aluminum wire or iron wire instead, in case of fire.
5, the use of household appliances such as refrigerators, freezers, washing machines, etc. , should be equipped with grounding wire socket according to the requirements of product use.
6. When repairing or replacing the lamp holder, even if the switch is turned off, do not touch it directly by hand to prevent electric shock.
The peak of electricity consumption in summer is coming. With the improvement of living standards and the increase of household appliances, faults caused by overload electricity use frequently occur. In order to ensure the safety of electricity consumption in summer, users should calculate their total electricity consumption before the summer comes and compare it with the maximum rated current of electric meters and power lines. If it is not enough, they should report to the power supply department in time to increase the capacity of the meter. It is best not to start high-power appliances such as air conditioners and microwave ovens at the same time, otherwise the instantaneous surge current will be too large, which will burn out the electric meter.
In areas with complex lines, the power supply should be installed by professionals, otherwise it will cause serious consequences. Copper wire and aluminum wire are prohibited. Replace the fuse; Signal transmission lines cannot be used instead of power lines; Medical leucorrhea and transparent belt cannot be used instead of insulating black belt.
Residents should actively guard against human invasion of lightning in thunderstorm season. There are four ways for induction lightning to invade: power lines, telephone lines, cable TV lines, external walls of houses or pillars. Therefore, it is very important to check the grounding wire regularly. Because if lightning strikes, the current generated by lightning will be led to the ground along the grounding lead to avoid electrical damage.
Many families keep the TV on standby or off after watching it. In fact, from the perspective of electricity safety, these two practices are unsafe. After watching TV, you should unplug the power cord while turning off the power supply, which can effectively prevent the TV from being struck by lightning in the human room. Similarly, all electrical appliances should be unplugged after use.
Electrical equipment must be placed in a dry, clean and ventilated place. It is best to electrify and heat electrical equipment once a week for a long time to prevent fainting, moisture and rust. Many people like to wipe the surface of TV screen with a wet rag when watching TV. This is not correct. Never wipe household appliances with a wet rag when electricity is on. It is best to adjust the electrical equipment to the energy-saving state, the air conditioning temperature should not be too low, and the number of refrigerator doors should be reduced as much as possible. Don't be too bright on TV or computer.
In summer, people are prone to sweating, so their resistance is correspondingly reduced, and the safety factor against electric shock is relatively weakened. Therefore, more attention should be paid to safety when touching electrical equipment to avoid electric shock accidents. If you find abnormal noise, smell, smoke, fire, etc. When, should immediately disconnect the power.
Consciously improve the awareness of safe use of electricity, adhere to the idea of "safety first, prevention first", ensure the safety of life and property, truly attach importance to safety from the heart and promote safe production.
2. Be familiar with the location (such as toll plaza, construction site, office, dormitory, etc.). ) air switch, the owner of the production site or dormitory. In case of fire, electric shock or other electrical accidents, cut off the power supply at the first time to avoid causing greater property losses and personal injury.
3. Do not connect wires without permission, do not hang clothes and sundries on wires or other electrical equipment, and do not install high-power or electrical equipment that does not meet national safety standards without permission. If necessary, it shall apply to the relevant departments for approval and be installed by electricians.
4. Do not disassemble lamps, switches, sockets and other electrical equipment without permission. Don't use the lamp to bake clothes or for other purposes. When there are abnormal phenomena such as smoke, arcing and burning smell inside the equipment, immediately cut off the power supply of the equipment and notify the electrician to carry out maintenance to avoid expanding the fault range and causing electric shock accidents; When the leakage protector (commonly known as leakage switch) trips, it shall not be reclosed without permission.
5. When using electrical equipment (such as hair dryer) in the bathroom or in a place with high humidity, it is necessary to ensure good indoor ventilation and avoid electric shock accidents due to poor electrical insulation.
6. Ensure good heat dissipation of electrical equipment (such as TV sets, electric water heaters, computers, stereos, etc.). ), don't pile up inflammable and explosive articles and sundries around, to prevent bad heat dissipation from damaging equipment or causing fire.
7. Cherish the power resources and form a good habit of using electricity safely and economically. When leaving or not using for a long time, please be sure to cut off the power supply (especially the electric heating appliances) before leaving.
8. Electrical appliances and electrical equipment with mechanical transmission devices must be protected by protective covers, shields or fences. Hands or body cannot enter the mechanical transmission position of the running equipment. When cleaning the equipment, it must be carried out when the power supply is cut off and the machine stops working and safety is ensured to prevent personal injury and death.
9. Don't climb high-voltage towers, fly kites or do other activities near high-voltage lines.
10, without the permission of the relevant departments, shall not enter the electrical room or electrical construction site without authorization.
That's basically it. I hope I can help you.
5. Power knowledge and safety
1. Why does the lighting switch have to be connected to the live wire? If the lighting switch is installed on the zero line, although the light is not on when it is turned off, the phase line of the lamp holder is still on, and people will think that the light is not on and will mistakenly think that it is in a power-off state.
In fact, the ground voltage of each point on the lamp is still a dangerous voltage of 220 volts. If people touch these actually charged parts when turning off the lights, it will cause an electric shock accident.
Therefore, all kinds of lighting switches or switches of single-phase small-capacity electrical equipment can only be connected in series on the live line to ensure safety. 2. How to correctly install the single-phase three hole socket? Why? Usually, single-phase electrical equipment, especially mobile electrical equipment, should use three-core plug and its supporting three hole socket.
There is a special protective zero (grounding) jack in three hole socket. When using zero protection, it is very dangerous for someone to directly connect the wiring pile head of this hole with the zero line that only leads into the socket at the bottom of the socket. Because in case the zero line of the power supply is disconnected, or the fire (phase) line and the zero line of the power supply are connected reversely, its shell and other metal parts will also bring the same voltage as the power supply, resulting in electric shock.
Therefore, when wiring, the special grounding jack should be connected with the special protective grounding wire. When zero protection is adopted, the zero line should be led out from the power supply side, and the zero line introduced into the socket should not be used nearby.
3. Why is it forbidden to bury plastic insulated wires directly in the wall? (1) Plastic insulated conductor will age and crack after long-term use, and the insulation level will be greatly reduced. When the line is overloaded or short-circuited, it is easier to accelerate the insulation damage. (2) Once the wall is damp, it will cause a large area of leakage and endanger personal safety.
(3) Plastic insulated wires are directly buried, which is not conducive to line maintenance and repair. 4. Why should I use a leakage protector? Leakage protector, also known as leakage protection switch, is a new type of electrical safety device. Its main purpose is: (1) to prevent electric shock accidents caused by leakage of electrical equipment and electrical lines.
(2) To prevent single-phase electric shock accidents in the process of electricity utilization. (3) Cut off the single-phase grounding fault in the operation of electrical equipment in time to prevent electrical fire accidents caused by leakage.
(4) With the improvement of people's living standards, the number of household appliances is increasing. In the process of using electricity, personal electric shock and fire accidents caused by defects in electrical equipment, improper use and unfavorable safety technical measures have brought undue losses to people's lives and property. The appearance of leakage protector provides a reliable and effective technical means for preventing all kinds of accidents, cutting off power supply in time and protecting equipment and personal safety. 5. What is the main cause of electric shock accident? Statistics show that the main causes of electric shock accidents are: (1) lack of knowledge about electricity safety, flying kites near high-voltage lines and climbing high-voltage poles to dig nests; After the low-voltage overhead line is disconnected, connect the fire line by hand without power failure; Touch the charged body by hand for live wiring at night; Touch the broken rubber knife switch with your hand.
(two) in violation of the operating rules, without taking necessary safety measures, unauthorized connection of lines or electrical equipment; Touch damaged equipment or wires; Wrong installation of live equipment; Electrified lighting; Online maintenance of power tools; Live mobile electrical equipment; Twist a light bulb, etc with wet hands. (3) The equipment is unqualified and the safety distance is not enough; The grounding resistance of two-wire and one-ground system is too large; The grounding wire is unqualified or disconnected; Insulation damage to wires, etc.
(4) The equipment is in disrepair, the line is blown off by strong wind or the pole is not repaired in time; Rubber breaker bakelite is damaged and not replaced in time; The damage of the motor lead makes the shell charged for a long time; The porcelain bottle is damaged, which makes the phase wire and the pull wire short-circuited, and the equipment shell is charged. (5) Due to other accidental reasons, I walked at night and ran into a broken live wire on the ground.
6. What rescue measures should be taken in case of electric shock? When an electric shock accident occurs, while ensuring the rescuer's own safety, we must first try to make the electric shock victim quickly get rid of the power supply, and then carry out the following emergency repair work. (1) Untie the tight clothes that hinder the breathing of the electrocuted person.
(2) Check the mouth of the person who gets an electric shock and clean up the mucus in the mouth. If there are any dentures, remove them. (3) immediately on-site rescue. If breathing stops, rescue with mouth-to-mouth artificial respiration. If the heart stops beating or vibrates irregularly, use artificial chest compression to rescue it.
Never interrupt for no reason. If there is a second person besides the rescuer at the scene, the following work should be done immediately: 1) Provide first aid tools and equipment.
2) convince others at the scene. 3) Keep sufficient lighting and air circulation at the site.
4) Report to the leader and ask the doctor to come to the rescue. Experimental research and statistics show that 90% patients can be saved if treatment is started from 1 min after electric shock. Only 10% chance can save lives if rescue is started 6 minutes after electric shock; But from 12 minutes after electric shock, the possibility of saving lives is extremely small.
So if you find someone getting an electric shock, you should race against time and take all possible measures. 7. What measures are there to use electricity safely at home? With the popularization and application of household appliances, it is very important to correctly master the knowledge of safe electricity use and ensure the safety of electricity use.
(1) Don't buy fake and shoddy "three noes" household products. (2) When using household appliances, there should be a complete and reliable power cord plug.
Household appliances with metal shell should be protected by grounding. (3) Switches and fuses cannot be installed on the ground wire and zero wire.
It is forbidden to connect the ground wire to the tap water and gas pipeline. (4) Don't touch the live equipment with wet hands, and don't wipe the live equipment with wet cloth.
(5) Don't connect wires privately, and don't move live equipment casually. (6) When repairing household appliances, you must first disconnect the power supply.
(7) When the power cord of household appliances is damaged, it should be replaced immediately or wrapped with insulating cloth. (8) When household appliances or wires catch fire, disconnect the power supply first, and then put out the fire.
8. How to prevent burning household appliances? The rated voltage of common household appliances is 220 volts, and the normal power supply voltage is around 220 volts. If the power supply voltage in the power supply line rises instantly due to natural disasters such as lightning strike, the zero line of the three-phase unbalanced household line is broken due to years of disrepair, or the phase voltage rises due to human misconnection, the current will increase, and household appliances will burn out due to overheating.
To prevent the burning of household appliances, we should start from the following aspects: First, try to disconnect the power supply when the electrical equipment is not in use; The second is to transform the old and disrepair connecting lines; The third is to install with overvoltage.
6. Pay attention to the people who use electricity safely on the construction site.
Precautions for safe electricity use in construction site: 1. All distribution boxes and switch boxes on the construction site shall be inspected and maintained once a month.
Maintenance and repair personnel must be professional electricians. When working, you must wear insulating articles and use electrical insulating tools.
2. When inspecting and repairing the distribution box and switch box, the corresponding power switch at the next higher level must be switched off, and a power-off sign should be hung. It is forbidden to work with electricity. 3, the disk in the distribution box should indicate the name and purpose of each circuit, and make a shunt mark.
4, the total distribution box door should be equipped with a lock, distribution box and switch box should appoint someone who's in charge. When the construction site stops working for more than 1 hour, the power switch box should be locked.
5, all kinds of electrical boxes are not allowed to put any sundry, and should be kept clean. No other temporary electrical equipment shall be hung in the box.
6, all kinds of electrical box fuse melt replacement, it is forbidden to use the melt does not conform to the specifications instead. Extended information: fire prevention measures for electricity consumption in the construction site 1, reasonable and correct conductor section selection, theoretically eliminating the overload use of the line, and careful selection of protection devices can protect the line within the specified time when the line is overloaded for a long time.
2. In summer, in view of the characteristics of rising temperature, easy fatigue of construction workers and great mood fluctuation, timely safety warning shall be given to remind all construction workers to take a rest and maintain vigorous energy. 3. Electric furnaces are strictly prohibited in the construction site. When using iodine tungsten lamp, the distance between lamps and combustible materials should be more than 30cm, and lamps with power exceeding 100w are not allowed indoors.
Bedside lamps are strictly prohibited. 4. When using electric welding machine, it is necessary to implement the system of using fire certificate, and have special supervision to check the carrying and intact conditions of construction equipment, safety equipment and labor protection articles.