Identification of strong electricity 1. Strong electricity is not equal to power consumption. A lot of strong electricity is used for power, such as motors, air conditioners and elevators, but it is also used to power computers, TVs and other equipment. For another example, the power of an electric vehicle is a 12V battery, which cannot be called strong electricity. 2. It cannot be demarcated by frequency or AC and DC. For example, 800KV DC transmission must belong to strong electricity. 3. It cannot be demarcated by the magnitude of the current. The working current of many high-voltage devices can be very small, but the communication power supply is low-voltage and high-current. The difference between strong electricity and weak point Strong electricity and weak electricity are relative concepts. Conceptually, the main difference is the difference in use, and the relationship between the two cannot be simply defined by the size of the voltage (if you have to specify the voltage to distinguish, then the 36V (human body safety voltage) ) above is classified as strong electricity, and below 36V (human body safety voltage) is classified as weak electricity.), both are related and different. The general principle of distinction is: the processing object of strong electricity is energy (electricity), which is characterized by voltage High, large current, high power and low frequency, the main consideration is to reduce loss and improve efficiency. The processing object of weak current is mainly information, that is, the transmission and control of information, which is characterized by low voltage, small current, low power and frequency. The main consideration is the effect of information transmission, such as the fidelity, speed, breadth and reliability of information transmission. They roughly differ as follows: (1) The AC frequency is different The frequency of strong electricity is generally 50Hz (Hz), which is called "power frequency", which means the frequency of industrial electricity: the frequency of weak electricity is often high frequency or ultra-high frequency, measured in KHz (kilohertz) and MHz (megahertz). (2) Different transmission methods The strong electricity is transmitted by transmission lines, and the weak electricity transmission is divided into wired and wireless. Radio transmits by electromagnetic waves. (3) The power, voltage and current are different Strong electric power is measured in KW (kilowatt), MW (megawatt), voltage is in V (volt), KV (kilovolt), current is in A (ampere), kA (kiloampere); weak current power is in W (watt) , mW (milliwatt) meter, voltage in V (volt), mV (millivolt), current in mA (milliampere), uA (microampere), so its circuit can be composed of printed circuits or integrated circuits. There are also high-frequency (hundreds of KHz) and intermediate-frequency equipment in strong electricity, but the voltage is higher and the current is also larger. Due to the development of modern technology, weak electricity has penetrated into the field of strong electricity, such as power electronic devices, wireless remote control, etc., but these can only be regarded as the weak electricity control part of strong electricity, which is different from the controlled strong electricity. According to the fundamental principle of weak electricity conduction signal and strong electricity conduction electric energy, we can easily distinguish strong electricity from weak electricity. For example, although electric shavers, flashlights, etc. only use two dry batteries (3V), we cannot consider them to be weak currents because the voltage and current of the electrical appliances are small, because they conduct electricity instead of signals, so they should belong to the strong current category. . From the above description, the relationship between the four can be roughly explained as follows: High voltage must include strong electricity, and strong electricity does not necessarily belong to high voltage; Low voltage must include weak current, and weak current must belong to low voltage; Low voltage is not necessarily strong electricity, and strong electricity is not necessarily low voltage.