-
Anonymous users2024-02-10According to the general human body resistance value, environmental resistance value, ergonomics of the comprehensive factors to determine: less than 50V AC and DC voltage does not cause substantial harm to the human body, and sensitive people do not appear "numb" feeling.
-
Anonymous users2024-02-09It should be no higher than 36V to call it a safe voltage! Because the voltage below 36 volts is not harmful to the human body, to be correct, there are five safe voltages: 6v12v24v36v42v
-
Anonymous users2024-02-08The safe voltage for the human body is 36V.
-
Anonymous users2024-02-07The human body can withstand the power supply of 36V, how can it be 24V.
-
Anonymous users2024-02-06First of all, the industry stipulates that the safety voltage is not 24V, but 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 an anti-electric shock protection device, the pure flow of electric intelligence allowed by the human body can generally be considered as 30mA.
The human body's response to electric currents:
8~10ma
The hand has difficulty getting rid of the electrodes, and there is a sharp pain (finger joints).
20~25ma
The hand is quickly paralyzed, does not automatically get rid of the electrodes, and has difficulty breathing.
50~80ma
Difficulty breathing, atria begin to tremble.
90~100ma
Breathing is paralyzed, and 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 buried, 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 large front 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.
-
Anonymous users2024-02-05The real reason for the electric shock of the human body is not the high voltage (the electrostatic voltage on the sweater is often higher than 36V, but the electricity does not kill people), but the large current passing through the human body.
The safe current that the human body can withstand is about 30mA, and the minimum resistance of the human body under wet conditions is about 800 ohms, according to Ohm's theorem, the safe voltage is.
-
Anonymous users2024-02-04The current flowing through the human body after a person is exposed to a 24V voltage will not cause harm to the human body and can be voluntarily removed by the person, so the 24V voltage is a safe voltage.
-
Anonymous users2024-02-03In general, voltages not higher than 36V are called safe voltages. This is in line with the results of simulation experiments, and of course this theory is suitable for the vast majority of people. Due to the air humidity of different environments, the characteristics of contact are different, and it is divided into 24V and 12V as the safety voltage.
-
Anonymous users2024-02-02Safety voltage refers to the voltage that does not directly cause death or disability to a person.
The "safe extra low voltage" that allows continuous contact under normal ambient conditions is 50 V.
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.
According to the characteristics of the production and work site, the use of the corresponding level of safety voltage is the fundamental measure to prevent the occurrence of electric shock accidents. The national standard "Safety Voltage" (GB3805-83) stipulates that the safety voltage rating in China is 42V, 36V, 24V, 12V and 6V, which should be selected according to factors such as the workplace, operator conditions, use mode, power supply mode, and line conditions.
-
Anonymous users2024-02-01It is the maximum voltage that the human body can withstand under normal circumstances, which is less than 36V, and it should be 36V in your question) because they are all less than 36V safe voltage, in order to ensure safety!
-
Anonymous users2024-01-31Less than 36V is a safe voltage, it does not mean that it is absolutely safe for the human body, but it is relative.
-
Anonymous users2024-01-30Safety voltage refers to the voltage socks that do not directly cause death or disability to people. The "safe extra-low voltage bleed" that allows continuous contact under normal environmental conditions is 24 V.
According to the different specific environmental conditions in China, the safety voltage value is specified as follows: 65V in buildings without a high risk of electric shock; 24V in buildings with a high risk of electric shock; 12V in buildings with a particular risk of electric shock.
-
Anonymous users2024-01-29Not higher than 36V is the safety voltage, the safety voltage is determined according to the resistance value of the person and the clothes worn by the person, and then it is higher than the person's tolerance.
CPU AMD440 3 Core 480 Motherboard Yingtai TA870+ 599 RAM Kingston 2G DDR3 1333 180 HDD WestJet 500G 7200rpm 270 Graphics Card Ӱ GT240 Black Edition X5 599 Monitor Samsung E1920N 759 You can choose a larger power supply Huntkey Calm King Diamond Version 228
Thanks to the inverter.
The internal MOSFETs are turned off when not working, and only the internal parasitic diodes. >>>More
The genes of the Han nation are originally high, all kinds of real history proves that people in ancient times are very tall, when Cao Cao was about 1.7 meters tall in the Three Kingdoms is considered short, the previous people were short because of the war (before the founding of New China), famine, (49 years later) physical labor and other problems, with the course of reform and opening up for decades, people's lives have been greatly improved, there has been a qualitative change, for example, now 10 children as long as they are willing to drink milk, the parents are very happy, It's annoying that children don't drink milk, they can't even eat milk before, and everyone says that Sichuan people are short, but in fact, from a historical point of view, Sichuan people also immigrated from the Central Plains, and the same gene can't be particularly short, look at the vast majority of men in Sichuan who are now more than 1.7 meters tall, and people who are more than 1.75 meters tall also account for a large proportion. Then why the people before Sichuan are generally shorter than other parts of the country, I think there are certain historical reasons, in the past, during the Anti-Japanese War, there were millions of Sichuan troops out of Sichuan, and in the end there were only hundreds of thousands left, plus very few came back from settling abroad, we all know that the soldiers are either strong or tall, so the remaining adult men in Sichuan can be imagined. Then there are 49 years later, Sichuan was once the top three provinces in the domestic economy, and there was a history of Sichuan grain ** Beijing (the older generation knows it), not to put more food ** Beijing, but Sichuan people themselves tighten their belts ** Beijing, many Sichuan people are hungry and can't eat yellow mud (that kind of yellow mud). >>>More
I think Lin Chong was the head of the 100,000 forbidden army guns and sticks before he went to Liangshan, so his force value must be very high.
Why is the yield of GMOs higher than that of non-GMOs? For the corn and soybean that are now being promoted, it cannot be said that the high yield of genetically modified organisms is not transferred, because it does not transfer to the yield increasing factor, it is to select a high-yield variety, and then transfer to the insect resistance or herbicide resistance factor.