Bathroom Business School
In recent years, the bathroom bath electric shock accidents occur repeatedly. According to statistics, the number of casualties caused by electrocution accidents in bathrooms in China is no less than 1000 per year, which has given us a wake-up call. Bathroom electric shock safety accidents occur frequently, tragedy after tragedy staged, the basic reason is due to the lack of installation of equipotential devices. What is equipotential? Come with the editor today to understand.
Must be indispensable bathroom equipotential details
According to the survey, nearly 90% of households are not clear about the concept of equipotential, not to mention the importance of installing equipotential devices in the bathroom. In order to prevent problems before they occur, we need to take the initiative to learn why to install the bathroom equipotential device.
First, residential bathroom should be equipped with equipotential
According to the latest “Residential Design Code”, residential bathrooms should be equipotential linkage. However, the actual survey shows that 70% of the owners do not install equipotential devices at home. Despite the regulations, the market penetration rate of equipotential connection protection is very low, and many owners do not even know the concept of equipotential.
Second, the concept of safety bathroom equipotential
As the name suggests, equipotential is the potential is equal, if the potential is not equal, there is a potential difference that voltage, coupled with the bathroom humid environment, people can be very electrical equipment and exposed metal electric shock. Therefore, the bathroom electrical devices, metal objects and conductive parts of all conductors linked together to reduce the potential difference to eliminate harm, which is the role of the bathroom installation equipotential.
Third, equipotential can defend against lightning induction
Thunderstorm, the building suffered a lightning strike. All metal objects in the building will generate induction electricity, especially the bathroom downpipes, heating pipes. If you take a shower in the bathroom at this time, you will be struck by induction electricity if you touch a metal object. If there is equipotential, the probability of suffering an induction attack will be greatly reduced.
Fourth, equipotential needs to be installed by the owner
Equipotential devices are usually reserved by the developer, but the need for professional master installation, including ancillary facilities may need to be purchased separately by the owner. In the electrical equipment generally into the bathroom today, the installation of equipotential is a guarantee of life safety. New homeowners should take the initiative to consult with professional decorators.
Avoid misconceptions Common misconceptions of bathroom equipotential
The installation of equipotential construction is more professional and requires an experienced electrician to be in charge. If owners have prior knowledge of the relevant knowledge, they can minimize construction misconceptions and reduce the threat to home security.
Misconception 1: Any bathroom does not need to do local equipotential linkage
Many people believe that the bathroom electrical appliances have been grounded through the PE line, and leakage protector protection, so metal appliances do not need to do local equipotential linkage.
Solution: Local equipotential connection and leakage protector are two different safety protection measures, can not replace each other. The role of equipotential is to ensure that a potential is basically equal, so as not to produce a large voltage injury to the human body. And the role of the ground is to ensure that the resistance between the leakage part and the earth is relatively small, thus ensuring that the current flowing through the human body is small. One is to ensure that the voltage is smaller, one is to ensure that the current is smaller.
Misconception 2: As long as the bathroom will have to do local equipotential
The human body impedance will be lowered when bathing, in the bathroom is particularly easy to electrocution. If the bathroom is installed with an electric water heater, or configured with a number of electrical equipment, the bathroom must do local equipotential linkage. And for some traditional neither electric water heater, and no additional electrical appliances in the bathroom, according to the situation can decide whether to do local equipotential.
Misconception 3: Local equipotential can lead to electric shock accidents
Local equipotential will bring the external high voltage into the room, resulting in electric shock accidents. It is better to introduce the potential from the grounding line to the grounding device to be safe.
Solution: As long as the potential is equal and no potential difference is generated, no electric shock accident will occur and there is no need to introduce potential into the grounding device. Local equipotential requirements in the local area of contact resistance is not greater than 3Ω, as long as the bathroom penetration into an equipotential body. Even if there is a high voltage outside, people in the bathroom can not touch the external high voltage conductor, it is also safe.
Misconception 4: with other measuring instruments instead of equipotential tester
Because there are fewer equipotential testers on the market, measurement work often encountered with grounding resistance meter, multimeter, etc. instead.
Solution: It is wrong to use measuring instruments other than the special tester for equipotential. Although an insulation resistance tester can test its conductivity, it cannot measure the resistance of an equipotential below 3Ω. The measurement current of multimeter is usually small and does not meet the national requirement of testing current not less than 0.2A. In order to prevent safety hazards, a special tester must be used for testing or voltammetric measurement.
Pay attention to the details of equipotential construction and acceptance specifications
Understanding the importance of the bathroom equipotential and some misconceptions about equipotential, let’s take a look at the construction of the bathroom equipotential installation considerations.
First, bathroom equipotential construction requirements
Bathroom local equipotential linkage, must be metal drainage pipes, metal bath, metal heating pipes and ground reinforcement network through the circuit connected to the equipotential terminal block. When the wall is a concrete wall, the reinforcement network in the wall should also be connected to the equipotential connection line. Metal floor drains, handrails, towel racks, soap boxes and other isolated things can be made according to the situation whether to do equipotential.
Second, equipotential terminal box installation location
Equipotential terminal box installed in the bathroom interior, generally buried in the tile can be, the circuit in the wall underground laying wire must use plastic pipe for protection. If the bathroom to pick up the transformation to move the inner wall, the equipotential also need to be re-modeled.
Third, pay attention to whether the bathroom has PE lines
Note that if the original bathroom does not have PE lines, local equipotential linkage shall not be connected to the PE lines outside the bathroom. Because the PE line may be due to the fault elsewhere and the electric potential, but can introduce the potential elsewhere. On the contrary, if there is a PE line in the bathroom, the local equipotential connection in the bathroom must be connected to the PE line.
Fourth, local equipotential construction acceptance
If the resistance between the terminal board and the metal conductor within the equipotential connection is not greater than 3 ohms, the equipotential connection can be considered effective. If poor conduction is found, jumper cables should be made. In the whole bathroom construction process, should always ensure that the equipotential conduction.