Basic knowledge of safe use of electricity

1、 Overview of Electricity
Use and maintain electrical equipment while taking necessary safety measures. Electricity is a convenient source of energy, and its widespread application has led to the second technological revolution in modern human history. It has effectively promoted the development of human society, created enormous wealth for humanity, and improved human life.
2、 The hazards of electricity
If electricity safety is not taken into account in production and daily life, it can also lead to disasters. For example, electric shock can cause personal injury, electrical sparks generated by equipment leakage may cause fires and explosions, and high-frequency electrical equipment can generate electromagnetic pollution.
3、 Electricity safety
1. How to use electricity safely
The scorching heat of summer is unbearable, and the air conditioning and electric fans are also turning on. Fire and electric shock accidents caused by the use of these appliances occur every year. How to use electricity safely and scientifically is a major issue that every household must pay attention to. Firstly, it is necessary to consider the load-bearing capacity of the energy meter and low-voltage lines. The power that an energy meter can withstand is approximately equal to the value of voltage multiplied by current. The voltage of household electricity is 220 volts. If a 2.5-ampere energy meter is installed at home, the power it can withstand is 550 watts, while a 600 watt rice cooker cannot be used. Based on this calculation, the power that a 5-ampere energy meter can withstand is 1100 watts.
Secondly, it is necessary to consider how many electrical appliances can be plugged into a socket. If the sum of the high power of all electrical appliances does not exceed the power of the socket, there is generally no problem. When using sockets with three or more pairs of sockets and simultaneously using high-power appliances such as air conditioners, rice cookers, rice cookers, and water heaters, the total power of these appliances should be calculated first. If the power limit of the socket is exceeded, the socket will heat up and burn out due to excessive current. In this case, the number of appliances used simultaneously should be reduced to keep the total power within the allowable range of the socket.
In addition, the installed knife switch must use corresponding standard fuses. Do not use other metal wires as substitutes, otherwise it may cause fires and damage electrical appliances. If a fire is caused by a household appliance catching fire, the power must be cut off first before putting out the fire to avoid electric shock and injury.
2. Safe use of electricity methods
The popularity of household appliances such as refrigerators, televisions, washing machines, and air conditioners has brought many conveniences to people's lives. However, it is important to pay attention to the safe use of the power supply to avoid unnecessary harm.
Electrical appliances with metal casings should use a three pin power plug. When some household appliances malfunction or become damp, the casing may leak electricity. Once the shell is charged and a two pin power socket is used, there is a possibility of electric shock upon contact with the human body. Household appliances with high power consumption should use separate power sockets. Because both wires and sockets have a specified current carrying capacity, if multiple electrical appliances use the same power socket, when the current exceeds its rated capacity, the wires will heat up and the plastic insulation sleeve may melt, leading to combustion.
When there is a large voltage fluctuation, a protector should be used. In daily life, sudden power outages or significant fluctuations in power supply voltage often occur, which poses a threat to refrigerators. If power is restored within a short period of time (3-5 minutes) after a power outage, the starting current borne by the compressor of the refrigerator will be several times greater than the normal starting current, which may burn out the compressor.
3、 Principles of Safe Electricity Use
(1) Not close to high-voltage charged bodies (outdoors, near high-voltage lines, transformers), and not in contact with low-voltage charged bodies.
(2) Do not use wet hands to turn the switch, insert or remove the plug.
(3) When installing and repairing electrical appliances, one should wear insulated shoes, stand on insulators, and cut off the power supply.
(4) It is prohibited to use copper wire instead of fuses and rubber tape instead of electrical insulation tape.
(5) Install electric shock protectors in the circuit and regularly check their sensitivity.
(6) During thunderstorms, do not use radios, recorders, or televisions, and unplug the power plug and television antenna plug. Do not use the phone temporarily. If necessary, use the hands-free function key.
(7) It is strictly prohibited to connect wires privately or randomly, and students are prohibited from using electric stoves, "fast heating" and other electrical appliances in the dormitory.
(8) Do not fly kites or engage in ball games under electric cables or wires.
4、 Other precautions
(1) The safe voltage for humans is not higher than 36 volts.
(2) Do not touch the metal rod of the pen tip when using a test pen.
(3) Electrical appliances with high power must be grounded.
(4) Cannot connect the live and ground wires with the body.
(5) The total power of the electrical appliances used should not be too high, otherwise it may cause excessive current and trigger a fire.
(6) When someone is electrocuted, do not pull them with your body. Immediately turn off the main switch and use a dry wooden stick to separate the person from the wire.