Electrical system composition
The basic return route of commonly used control circuits consists of the following parts.
(1) Power supply circuit. There are various power sources for the power supply circuit, including AC380V and 220V.
(2) Protection circuit. There are various working power sources for the protection (auxiliary) circuit, including single-phase 220, 36V or DC 220, 24V, etc., which provide various protections for electrical equipment and circuits such as short circuit, overload, and voltage loss. They are composed of protective components such as fuses, thermal relays, voltage loss coils, rectifier components, and voltage stabilizing components.
(3) Signal circuit. A circuit that can timely reflect or display the normal and abnormal working status information of equipment and circuits, such as signal lights of different colors, audio equipment with different sounds, etc.
(4) Automatic and manual circuits. In order to improve work efficiency, electrical equipment generally has automatic links. However, in installation, debugging, and emergency handling, manual links need to be set in the control circuit to achieve automatic and manual conversion through combination switches or transfer switches.
(5) Brake parking circuit. The control process of cutting off the power supply of the circuit and taking certain braking measures to quickly stop the motor, such as energy consumption braking, power reverse connection braking, reverse pull reverse connection braking, and regenerative power generation braking.
(6) Self locking and locking are the same path. After the start button is released, the circuit remains energized and the electrical equipment can continue to work, which is called a self-locking link. For example, the moving and closing contacts of a contactor are connected in series in a coil circuit. Two or more electrical devices and components, in order to ensure the safety and reliability of equipment operation, can only be started with one device powered on, and the other cannot be started with the other device powered on, which is called the locking link. If the dynamic break contacts of two contactors are connected in series in the other coil circuit.
In general, the flow meter is a metering product that conforms to the general value law. The higher the accuracy, the higher the price, the higher the weight, the higher the price, the more functions, and the higher the price. The imported products are more expensive than domestic ones. expensive.
Automatic furnace temperature control --- refers to automatically turning on or off the heat source energy supplied to the furnace according to the deviation of the furnace temperature from a given temperature, or continuously changing the amount of heat source energy to stabilize the furnace temperature within a given temperature range. Meet the needs of heat treatment process.
China's metallurgy, machinery, building materials and other industries have about 10,000 flame furnaces for industrial heating and heat treatment, which consume a large amount of fossil fuels each year, accounting for about 8% of the total energy consumption of China's industrial enterprises. Although China is a large energy producing country, it is also a large energy consuming country. The effective use of energy has become an important link restricting China's economic development. Among them, especially fossil energy is a non-renewable energy. A large amount of carbon dioxide and harmful gases emitted after combustion have seriously polluted the atmosphere and damaged our living environment. Therefore, saving energy and protecting the environment are great achievements for the benefit of mankind and future generations.