Low-voltage switchgear is one of our common electrical equipment, but there are some things inside the switchgear, what are its main components, what is the role, many people are not too understanding. Today, Tongyida Xiaobian will introduce the main components and functions of the low-voltage switchgear.

First, the main components of low-voltage power distribution cabinet

The low-voltage power distribution cabinet is mainly composed of an incoming line cabinet, an outlet cabinet, a capacitor cabinet, a metering cabinet, and the like.

Incoming cabinet: Also known as the receiving cabinet, it is used to receive electrical energy from the grid (from the incoming line to the bus), and is generally equipped with circuit breakers, CT, PT, isolation knives and other components.

Outlet cabinet: also called feeder cabinet or power distribution cabinet, is the equipment used to distribute electric energy (from bus to each outlet), and is generally equipped with circuit breaker, CT, PT, isolation knife and other components.

Busbar connection cabinet: also called busbar branching cabinet, which is used to connect two busbars (from busbar to busbar). In single busbar section and double busbar system, busbar connection is often used to meet different operating modes. The requirements or guarantees a selective removal load in the event of a fault.

PT cabinet: The voltage transformer cabinet is usually installed directly on the busbar to detect the bus voltage and realize the protection function. Internally, the main voltage transformer PT, isolation knife, fuse and lightning arrester are installed.

Isolation cabinet: It is used to isolate the busbars at both ends or to isolate the power receiving equipment from the power supply equipment. It can provide the operator with a visible end point for maintenance and repair work. Since the isolation cabinet does not have the ability to interrupt and switch the load current, the handrail of the isolation cabinet cannot be pushed and pulled in the case where the matching circuit breaker is closed. In general applications, it is necessary to set the interlock between the auxiliary contact of the circuit breaker and the isolated handcart to prevent the operator from misoperation.

Capacitor cabinet: also called compensation cabinet, used to improve the power factor of the power grid, or reactive power compensation, the main components are the group of capacitor banks, switching control loops and fuses in parallel Use electrical appliances. Generally installed side by side with the incoming line cabinet, one or more capacitor cabinets can be operated side by side. After the capacitor cabinet is disconnected from the grid, since the capacitor bank needs a period of time to complete the discharge process, it is not possible to directly touch the components in the cabinet, especially the capacitor bank; within a certain period of time after the power failure (according to the capacitor bank) Depending on the size of the capacity, such as: 1 minute), re-closing is not allowed to avoid overvoltage damage to the capacitor. When making automatic control functions, it is also necessary to pay attention to the reasonable number of switching times of each group of capacitor banks, so as to avoid a group of capacitors being damaged, while other groups rarely switch.

Metering cabinet: mainly used for metering electric energy (kilowatt hours), high voltage and low voltage. Generally installed with isolating switch, fuse, CT, PT, active energy meter (traditional meter or digital meter), no Power meters, relays, and some other auxiliary secondary equipment (such as load monitors, etc.).

Second, the role of low-voltage power distribution cabinet

The rated current of the low-voltage power distribution cabinet is AC 50Hz, rated voltage 380v power distribution system, the main function is to distribute power, distribute the voltage through the transformer to each power unit, and use it for power and lighting distribution in low-voltage power distribution system. Use. The product has strong breaking ability, good dynamic thermal stability, flexible electrical scheme, convenient combination, series, practicality and novel structure.

1, easy to properly configure the power supply

2. When the line is faulty, it is beneficial to control the fault range and it is convenient to quickly find the fault point and eliminate it in time.

3, it is convenient to arrange the line maintenance, and there is no need for a large area of power outage.

4. It is convenient to place various protection devices such as fuses (fuse) to prevent short circuit and air switch to prevent overload in the power distribution cabinet.