In the electric water heater industry, the anti-electric wall has become synonymous with the safety of electric water heaters, and even some manufacturers want to include the anti-electric wall in the national standard. So can the electricity-proof wall be as safe as the electric water heater product advertised? Why around 2003, European and American countries said that the listing of a brand in China was purely a terrorist sale? Let's analyze the instructions for the use of the electricity-proof wall:
I. Use
Suitable for safety protection products of any electric water heater. After the water heater is equipped with the electricity-proof wall, no matter what kind of leakage accident happens to the water heater, no matter whether the water heater has a ground wire or not, there is no danger of electric shock under the electricity-proof wall, which ensures the personal safety during bathing.
Analysis:
1, "No matter what kind of leakage accident happens to the water heater"
Is the water heater with metal shell leaking? What about the electricity on the button? Can the electricity-proof wall be protected? If our users still think that it is safe to operate the water heater in this case, they will be negligent because of the electricity-proof wall, resulting in serious consequences.
2. "Is the water heater grounded?"
Is the good grounding required by the state a joke? So, are the products of our factory still grounded? If there is no ground wire, it is the same as the first result. Grounding means charging the shell, charging the button, and taking away the current wherever the product can be charged. If it is only isolated, and only the effluent is not charged, is it safe to leak electricity? Who can guarantee that users will not touch it? Just like when the flood rises, we just want to block up the flood without considering how to discharge it, and the consequences can be imagined.
3. "There is no danger of electric shock in the following parts of the electricity-proof wall."
Just like the above two. What about the one above the electricity-proof wall? Who can guarantee that users will not touch it? Just like our car, isn't it necessary to reduce vibration to keep the car from bumping? Maybe the vibration reduction is increased, the car shakes more, the road is not repaired well, and the tires are more likely to burst. Can our safety be guaranteed?
4. "To ensure personal safety during bathing"
In the above case, the water heater can also ensure the personal safety in the bathing process, which means that the water heater itself has no leakage protection device and can still take a bath normally in the case of leakage? Then, of course, it is impossible for us users to know that the water heater has leakage. They will operate buttons, water valves and touch any part of the water heater with confidence. Even if the water dies, are our users safe at this time? This is a concern about "personal safety in the shower", and the rest are not safe.
Therefore, it is very important to truly use electricity safely, not by the anti-electricity wall, but by the safety and protection function of the water heater itself. When leakage occurs, it can automatically protect and cut off all power supplies in the machine and give an alarm to remind to ensure safety. If the protection fails, you can't just rely on the electricity-proof wall, which will lead to the above dangers. It depends on the structural safety of our products. In the case of protection failure, the shell can't be charged, the buttons can't be charged, and the water inlet and outlet must be made of non-metallic materials. As long as the air gap and creepage distance between each charged body and the charged shell, keys and other parts that may contact the human body are standard, it can not only ensure the safety of electricity use, but also be foolproof.
Two. principle
"Electrical insulation wall" is a kind of abbreviation, and the accurate expression should be "water resistance attenuation isolation method".
Generally speaking, water is a conductor, and it is very dangerous to contact electricity. In fact, any object has resistance, so under the premise of economy, it may be transformed into a tool to meet human needs and benefit mankind. This is the case with the "insulation wall".
"Thermal insulation wall" (that is, water resistance attenuation isolation method) uses the resistance of water itself (for example, the national standard stipulates that the resistivity of tap water should be greater than1300 Ω. Cm 15℃), and the "insulation wall" is formed by selecting materials (insulation materials) and determining the diameter and distance of water pipes in the electric water heater. When the electric water heater is electrified, even if there is electricity, the water in the heating water tank will be attenuated by the resistance of the water itself when it passes through the "insulation wall", so as to achieve the purpose of isolating electricity, so that the water inlet and outlet ends of the water heater can reach almost zero voltage and extremely weak current below 0.02mA/kw.
Using the "insulation wall" technology can not only block the possible leakage of the electric water heater itself, but also block the security threat to the shower caused by the live ground wire or water pipe. Therefore, the water heater adopts the technology of "insulation wall", which fully ensures the safety of people's bathing.
Analysis:
1, "Water resistance attenuation isolation method"
Water-H2O itself is an insulator, because there are impurities, metal substances and other conductive substances in water, which makes water no longer pure H2O, so it has certain conductivity. The resistance of water is related to the conductive substances in water. The resistance of water is different in different parts of China. So how big should I use the electricity-proof wall? I don't think anyone can make it clear. In fact, the electricity-proof wall we are afraid of is to open a small water channel in the plastic body to increase the length of the channel and extend the distance of the waterway in the insulating plastic body to increase the water resistance. According to the water quality characteristics, how long is this distance? There is no definitive conclusion. Generally, the length of the tunnel in the electricity-proof wall is 30 to 50 cm, and the two halves are combined into one, separated by a sealing film. If the sealing membrane is aged and perforated, water will flow directly from the entrance to the exit of the electricity-proof wall, with a distance of less than 5 cm. Can you prevent electricity at this time? In fact, if the water nozzle of our water heater is plastic, and the water pipe is about 1.5m, and the inside of the hose is insulated by plastic, then it is an electricity-proof wall about 1.5m, which is several times longer than the feared electricity-proof wall, and the water resistance is greater and safer. Therefore, when choosing an electric water heater, never choose a metal faucet for beauty.
2. "Using the technology of' insulation wall' can not only block the potential leakage of the electric water heater itself, but also block the security threat to the shower caused by the electrification of the ground wire or water pipe."
As mentioned above, the water leakage of the electric water heater itself indicates the quality problem of the water heater itself. The ground wire is charged, so are the shells of other electrical appliances, and even the shells of all electrical appliances dare not touch it. I want to ask: shall we take a bath or turn on the water first? Of course, there is a chance first, that is, first contact with the shell. Can the electricity barrier work at this time? Moreover, the air in the home has jumped from the beginning, and the user does not use electricity at home; Is the water pipe charged? In the same way, let's boil the water first and then take a bath when the water comes out. Can the electricity-proof wall stop the electricity on the water pipe valve? Can our washing machine work? Are all the taps working? Can you "fully ensure the safety of people taking a bath"? It probably happened before the shower. Just like someone jumped on the 10 floor, the lifeguard installed an air cushion on the 1 1 floor. Therefore, our water heater should consider safety from its own structure and quality, rather than relying on safety issues. You can't solve the problem of live ground wire and water pipe by installing 10 thousand anti-electricity walls. That's an environmental problem and can only be solved by relevant departments.
3. As many people know, a well-known brand first threatened users with the danger of electric water heater leakage, and then launched an anti-electric wall for users to snap up. This is what European and American countries call terrorist sales, but everyone ignores a problem. He sold the electric water heater so horribly and the electricity-proof wall was so good. Why didn't he inform the previous users to install the anti-electricity wall when he introduced it? Why didn't his washing machine and other electrical appliances have anti-electricity walls, and didn't his previous users live well?
Three. Installation and use
1. Wrap the raw material belt around the water inlet and outlet of the water heater for 2-3 times.
2. Pad the sealing ring in the hole of the insulating wall.
3. Installing insulation walls on the inlet pipe and outlet pipe can prevent the risk of electric leakage inside and outside the water heater.
4. After the installation, test the water heater to see if the insulation wall leaks. If there is water leakage, tighten it moderately until there is no leakage. If it leaks, stop using it.
Four. preventive measure
1. The insulation wall has been sealed in the factory. In any case, the user shall not disassemble it by himself, otherwise the user shall be responsible for all the consequences.
2. What kind of leakage accident happened when the user abides by the rules of use, and whether there is a ground wire, as long as the insulation wall does not leak electricity; When in use, it does not touch the upper joint of the insulation wall and the main body of the water heater on it, so as to ensure personal safety.
Analysis:
From the above second point of view, it can completely confirm the results of the previous analysis, "as long as the insulation wall does not leak; When in use, personal safety can be ensured without touching the upper joint of the insulation wall and the main part of the water heater above. " What about water leakage? If you don't touch the place above the electricity-proof wall, how can you not turn on the water heater? In a word, we can only guarantee that the water is free of charge, but if the user thinks it is safe, he can feel free to touch other places, and the result will be more dangerous. The leakage of the electricity-proof wall includes external leakage and internal leakage, the external leakage is visible, and the internal leakage, that is, the leakage in the middle of the sealing film, is invisible. Access is connected, that is, the above-mentioned waterway with insulation less than 5 cm, so the safety of the water outlet cannot be guaranteed.
Main technical indicators of verb (verb abbreviation)
Under the voltage of 1.220 V, the leakage current is less than 1mA (international standard 5mA), and you can take a bath if it leaks. Through the above analysis, can you still? )
2. The bearing capacity is 1.5MPa.
3. Temperature resistance 100 degrees Celsius
4. The water resistance is greater than or equal to 1mω.
5. Standard 4-tap
Therefore, water heaters with electricity-proof walls may not be really safe. What is truly safe must be products that pay attention to quality, internal structure, technology and materials. Electricity protection can only be an auxiliary protection configuration at most. Can not be used as the safety dependence of water heater products.
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