1、 What is the safe voltage of human body?
The safe voltage of the human body is actually based on the maximum current allowed to pass through the human body is 32mA, because the greater the current on the human body, the greater the harm to the human body. But the resistance of the body is certain when the human body is dry. According to u = 1R, it can be calculated that u is 36 V, but the safe voltage may be reduced to 24 V or 12 V when the human body or the environment is wet, and the safe voltage will be higher than 36 V when the human body is dry. For example, the output voltage of the welding machine is 60v-70v. In short, we should pay attention to observe whether the human body, the ground and the environment are moist in our work or life. If the drying conditions are not met, even if the safe voltage is 36V, do not touch it, and corresponding measures shall be taken.
2、 How much harm does 220 volt voltage do to human body electric shock?
In our daily life, the most exposed voltage in our work is 220 v. Such as home lighting, home appliances. In industrial and mining enterprises, the most common 220 V voltage, such as lighting, electric hand drill, angle grinder, sewing machine, computer, printer, electric stove, etc.
There are three ways of electric shock to human body: 1. Single phase electric shock, electric shock when a person touches a phase electrified body on the ground or other grounding body. 2. Two phase electric shock refers to the electric shock when two parts of human body touch two-phase electrified bodies at the same time. 3. Step voltage electric shock refers to the electric shock when the human body enters into the scattered flow field of the grounding current. Because of the uneven potential distribution on the ground and the different potential between two feet, the two potential differences are called step voltage. The step voltage is related to the distance between the person and the grounding body. When one foot of a person crosses the grounding body, the step voltage is the maximum. The farther away the person is from the grounding body, the smaller the step voltage is. When the distance from the grounding body is more than 20 meters, the step voltage is close to zero.
Electric shock can cause different degrees of damage to human body and internal tissues. This kind of injury can be divided into electric shock and electric injury. Electric shock refers to the serious damage of internal tissue caused by electric current passing through human body. Electric injury will make people feel hot and numb all over the body, and the muscles will twitch involuntarily and gradually lose consciousness. If the current continues to pass through the human body, the heart, ventilator energy and nervous system of the electrocuted person will be injured until the breathing stops, and the cardiac activity will stop to die. Electric injury refers to the local injury caused by electric current to the outside of human body. From the appearance of electric injury, there are generally electric arc burns, electric branding and molten metal penetrating into the skin (called skin metallization) and other injuries. In a word, when people get electric shock, because of the electric current passing through the human body and the occurrence of electric arc, they often burn the human body and cause death in serious cases.
Except for the safe voltage below 36V, it will be dangerous if people touch it above this voltage. It can be imagined how much 220 volts is 6 times of 36 volts and how serious the damage is.
Power Department of Yadong company