Views: 3 Author: Site Editor Publish Time: 2021-05-22 Origin: Site
According to the requirements of power supply system:
(1) Power distribution equipment, collectively referred to as power distribution center. They are installed in the substation of the enterprise and distribute the power to the lower level distribution equipment in different places. The equipment is close to the step-down transformer, so the requirements of electrical parameters are high, and the output circuit capacity is also large.
(2) Secondary distribution equipment is the general name of power distribution cabinet and motor control center. The power distribution cabinet is used in the situation where the load is scattered and the circuit is less; Motor control center is used in the situation of concentrated load and more circuits. They distribute the electric energy of a certain circuit of the power distribution equipment to the nearest load. This class of equipment shall provide protection, monitoring and control for the load.
(3) The final power distribution equipment is called lighting power distribution box. They are far away from the power supply center and are distributed small capacity distribution equipment.
According to structural features and uses:
(1) Fixed panel switch cabinet, often called switch board or distribution panel. It is a kind of open type switch cabinet with panel barrier. The front side has protective effect, and the back and side can still touch the live parts. The protection level is low. It can only be used in industrial and mining enterprises with low requirements for continuity and reliability of power supply for centralized power supply in Substation.
(2) Protective (i.e. enclosed) switch cabinet refers to a low-voltage switch cabinet with all sides closed except the mounting surface. The switch, protection, monitoring control and other electrical components of the cabinet are all installed in a closed shell made of steel or insulating materials, which can be reliably installed on or off the wall. Each circuit in the cabinet can be isolated without isolation measures, or with grounded metal plate or insulating plate. Generally, the door is mechanically interlocked with the main switch. In addition, there is a protective platform type switch cabinet (i.e. console), which is equipped with control, measurement, signal and other electrical appliances. The protective switch cabinet is mainly used as the power distribution device in the process site.
(3) Drawer type switch cabinet. This kind of switch cabinet is made of steel plate with a closed shell, and the electrical components in and out of the line circuit are installed in the extractable drawer, forming a functional unit that can complete a certain type of power supply task. The functional unit and bus or cable are separated by grounded metal plate or plastic functional plate to form three areas: bus, functional unit and cable. There are also isolation measures between each functional unit. Drawer type switch cabinet has high reliability, safety and interchangeability. It is a relatively advanced switch cabinet. Most of the switch cabinets produced are drawer type switch cabinets. They are suitable for industrial and mining enterprises and high-rise buildings that require high reliability of power supply, as the distribution center of centralized control.
(4) Power and lighting distribution control box. Most of them are closed vertical installation. Due to different use occasions, the degree of protection of the shell is also different. They are mainly used as power distribution devices in the production site of industrial and mining enterprises.
Features and functions:
1. It is convenient for management and maintenance when circuit failure occurs.
2. Distribution box, distribution cabinet, distribution panel, distribution panel, etc. are complete sets of devices for centralized installation of switches, instruments, etc.
3. There are two kinds of commonly used distribution boxes: wooden and iron.
4. Purpose of distribution box: convenient to stop and transmit power, play the role of measuring and judging stop and transmit power.