What is the safe voltage on the passenger ropeway support

The correct answer is: Option A Answer Analysis: A

The level of the rated value of the safety voltage specified in our country is volts. When the voltage used in electrical equipment exceeds the safe voltage, protective measures must be taken to prevent direct contact with live bodies according to regulations.

The safe voltage is the voltage that does not directly cause death or disability, and the "safe extra low voltage" that allows continuous contact under normal environmental conditions is 36V.

The industry stipulates that the safety voltage is not higher than 36V, the continuous contact safety voltage is 24V, and the safety current is 10mA. The degree of harm to the human body of electric shock mainly depends on the size of the current passing through the human body and the length of the power on time.

According to China's national standard GB3805-83 "Safety Voltage", there are five levels of safety voltage value. At the same time, it is also stipulated that when the electrical equipment is paralyzed by more than 24V, protective measures against direct contact with the charged body shall be taken.

The so-called safety voltage mainly refers to the voltage that is not harmful to personal safety. The regulations on safety voltage vary slightly from country to country, including 50V, 40V, 36V or 24V (referring to power frequency alternating current). According to the different specific environmental conditions, China stipulates the safety voltage as:

65V in buildings where there is no high risk of electric shock;

36V in buildings with a high risk of electric shock;

12V in buildings with a particular risk of electric shock.

The safety voltage is not absolutely safe, and there have been accidents where electrocution has occurred at voltages such as 36V. This is because the resistance of the human body varies from person to person and is affected by environmental conditions, etc. If the operation site is narrow and wet, or if people are working in metal containers, mines, and pipelines, it is difficult to get rid of the charged body after an electric shock, and even if a safe voltage of 36V is used, there is still a possibility of death from electric shock.

Therefore, when using a safety voltage, the corresponding safety voltage should also be used depending on the environment. Usually 12V is the absolute safety voltage.

The national standard "Safety Voltage" (GB3805-83) stipulates that the rated value of safety voltage in China is 42V, 36V, 24V, 12V and 6V, which should be selected according to factors such as the special place of the operation site, the conditions of the operator, the use mode, the power supply mode, and the line condition. For example, hand-held power tools used in particularly hazardous environments should use 42V ultra-low voltage; Hand-held lights and spot lights used in environments where there is a risk of electric shock should be used at 36V or 24V ultra-low voltage; The hand-held lights used in particularly dangerous environments such as metal containers and particularly humid places use 12V ultra-low voltage; Underwater operations and other places should use 6V ultra-low voltage.

If it is not required to have a special working environment, the general safety voltage refers to 36V, because in the power frequency current, the current value of the human body can get rid of the power supply is about 30mA, and the human body resistance is generally in the range of 1000 2000 in a dry environment.

Delixi safety voltage is AC 30 volts, DC 50 volts.

A safety voltage is a series of voltages used to supply power from a specific power source to prevent electric shock. The upper limit of this voltage series, i.e. the voltage between two conductors or between either conductor and ground, does not exceed the AC RMS of 50 volts in any case. China stipulates that the level of the rated value of the safety voltage is volts.

When the voltage used in the electrical device exceeds the safe voltage, protective measures must be taken to prevent direct contact with the live body according to the regulations.

Excerpt from State Grid.

Industry regulations The safety voltage is 36V and the safe current is 10mA for the following reasons:

The degree of harm to the human body of electric shock mainly depends on the size of the current passing through the human body and the length of time it is on. The greater the current intensity, the greater the fatal danger; The longer it lasts, the more likely it is to die. The minimum value of current that can be perceived by a person is called the perceived current, which is 1 mA for AC and 5 mA for DC; The maximum current that a person can get rid of after an electric shock is called getting rid of the current, which is 10mA for AC and 50mA for DC; The current that is life-threatening in a relatively short period of time is called a lethal current, such as a current of 100mA passing through the human body for 1s, which can be enough to make a person fatal, so the lethal current is 50mA.

In the case of protection against electric shock, the current allowed by the human body can generally be considered as 30mA.

The human body's response to electric currents:

8 10mA hands have difficulty getting rid of the electrodes and have a sharp pain (finger joints).

20 25mA hands quickly paralyzed, unable to get rid of electrodes automatically, breathing difficult.

50 80mA is difficult to breathe, and the atria begin to tremble.

90 100mA respiratory paralysis, after three seconds the heart begins to paralyze and stops beating.

According to Ohm's law (i u r), it can be known that the magnitude of the current flowing through the body is related to the applied voltage and the resistance of the body. In addition to the human body's own resistance, the human body resistance should also be attached to the human body other than clothing, shoes, pants and other resistance, although the human body resistance can generally reach 5000, however, there are many factors that affect the human body resistance, such as damp sweating, conductive dust, increasing the contact area and pressure with the charged body, as well as the wet oil stain of clothes, shoes, socks, etc., can reduce the human body resistance, so usually the size of the current flowing through the human body can not be calculated in advance. Therefore, in order to determine the safety conditions, the safety current is often not used, but the safety voltage is used to estimate

Under normal circumstances, that is, in a dry and dangerous environment with a greater risk of electric shock, the safety voltage is specified at 36V, and for wet and electric shock environments (such as metal containers, pipeline welding and maintenance), the safety voltage is specified as 12V, so that the current through the human body during electric shock can be limited to a small range, which can ensure personal safety to a certain extent.

Taken from Yahoo.

Upstairs is right, but, in fact, it is also divided into people, when the voltage is close to 36, it is best not to move if the body is bad

Below 36V is a safe voltage and will not cause harm to the human body.

Generally speaking. Less than or equal to 36....

.If it's a rainy day. The air humidity is high. It's a different story.

Below 36V is the safe voltage 0-36V.

It is stipulated that the level of safety voltage rating in China is 42V, 36V, 24V, 12V and 6V, which should be selected according to the workplace, operator conditions, use mode and power supply mode.

Expansion: The safe voltage refers to the voltage that does not cause direct death or disability, and the safe ultra-low voltage that allows continuous contact under general environmental conditions is 36V. The industry stipulates that the safety voltage is not higher than 36V, the continuous contact safety voltage is 24V, and the safety current is 10mA. The degree of harm to the human body of electric shock mainly depends on the size of the current passing through the human body and the length of the power on time.

Introduction: The greater the current intensity, the greater the fatal danger; The longer it lasts, the more likely it is to die. The minimum current value that can cause a person to feel is called the perceived current, AC is 1 mA, DC is 5 mA, the maximum current that can get rid of itself after an electric shock is called the escape current, AC is 10 mA, DC is 50 mA, and the current that endangers life in a relatively short period of time is called a fatal current.

The safety voltage is generally referred to as a voltage of 36 volts or less. Because when a person is electrocuted, the current is the direct factor that causes the injury, and the larger the current, the more serious the injury.

Experience has proved that when the current passing through the human body exceeds 50 milliamperes, the electric shock injury will endanger the life of the person, and it is not easy for the electrocuted person to get out of the power supply by himself.

The resistance of the human body is generally between 800 ohms and 10,000 ohms. Calculate the resistance of the human body at 800 ohms, and add 40 volts to the human body through a current of 50 milliamps. Therefore, in general, a voltage of less than 36 volts is specified as a safe voltage.

But it should be noted that the resistance of the human body drops dramatically in some cases. If the workplace is very humid or has corrosive gases; ** Sweat or splashed wet by conductive solution; There are conductive dust, etc. At this time, 36 volts is not a safe voltage, and the voltage added to the human body is not more than 12 volts, so the 12 volt voltage is called absolute safe electricity.

Within 36 volts is the safe voltage.

The safety voltage is the voltage that does not endanger life safety under certain conditions and for a certain period of time. The limit of the safe voltage is the voltage value that must not be exceeded between any two conductors under any circumstances. China's standard stipulates that the limit of the effective value of power frequency safety voltage is 50V.

The rated values of power frequency effective value in China are 42V, 36V, 24V, 12V, and 6V. Portable power tools used in particularly hazardous environments should use a safe voltage of 42V; Hand-held lights and local lights used in environments with electric shock hazards should use 36V and 24V safety voltages; 12V safe voltage should be used in narrow and inconvenient environments such as metal containers, tunnels, wells and surrounding areas with large grounding conductors; A safe voltage of 6V should be used in special places such as water operations.

The safety voltage is the voltage that does not endanger life safety under certain conditions and for a certain period of time. The limit of the safe voltage is the voltage value that must not be exceeded between any two conductors under any circumstances. China's standard stipulates that the limit of the effective value of power frequency safety voltage is 50V.

The rated values of power frequency effective value in China are 42V, 36V, 24V, 12V, and 6V. Portable power tools used in particularly hazardous environments should use a safe voltage of 42V; Hand-held lights and local lights used in environments with electric shock hazards should use 36V and 24V safety voltages; 12V safe voltage should be used in narrow and inconvenient environments such as metal containers, tunnels, wells and surrounding areas with large grounding conductors; A safe voltage of 6V should be used in special places such as water operations.

What is Safe Voltage? Star Awareness Project

Safety voltage refers to the voltage that does not directly cause death or disability to a person.

Under normal circumstances, that is, in a dry environment with a greater risk of electric shock, the safety voltage is specified at 24V, and for wet environments with a greater risk of electric shock (such as metal containers, pipeline welding and maintenance), the safety voltage is specified as 12V.

A voltage not higher than 36V is a safe voltage.

Safety voltage refers to the voltage that does not directly cause death or disability to a person. The safety voltage is related to the resistance of the human body. The resistance of the human body is composed of two parts: the resistance in the body and the resistance.

The internal resistance is about 500 ohms, independent of the contact voltage. **Resistance varies with the dry and wet cleaning conditions of the surface and the contact area. The lower limit of the human body resistance is generally 1700 ohms, and the average value is 2000 ohms.

Since the safety current is 30mA, multiply the two to about 50V, which is called the "safe floor voltage" that allows continuous contact under normal environmental conditions, and the current national standard GB 50054-1995 "Low-voltage Power Distribution Design Code" also stipulates: "The environment where the equipment is located is a normal environment, and the safety voltage limit for personal electric shock is 50V".

220V household single-phase voltage, +

5% is within the normal value (209V - 231V).

AC 36V or less is the safe voltage. 42V is not DC voltage?

Definition: A series of voltages powered by a specific power source for the purpose of preventing electric shock. The upper limit of this voltage series, in any case, between two conductors or between either conductor and ground shall not exceed the AC (50-500Hz) RMS value of 50V.

Note: In addition to the use of independent power supply, the input circuit and output circuit of the power supply of safety voltage must be isolated from the circuit. Circuits operating at safe voltages must be electrically isolated from other electrical systems and any unrelated conductive parts. The upper limit of direct current will be supplemented at a later date.

The national standard safety voltage rating is 42, 36, 24, 12, 6V.

When electrical equipment uses a safe voltage of more than 24V, protective measures must be taken against direct contact with live bodies.

It's 36v, absolutely.

The industry stipulates that the safety voltage is not higher than 36V, and the safe current is 10mA, and the degree of harm to the human body by electric shock mainly depends on the size of the current passing through the human body and the length of time of energizing. The greater the current intensity, the greater the fatal danger;

The "safe extra low voltage" that allows continuous contact under normal ambient conditions is 50 V

Under normal circumstances, that is, in a dry and high risk of electric shock, the safety voltage is specified as 36V

Safety voltage: 36 volts, 24 volts, 12 volts, (6 volts).

12v At least on the car, 12 is used