What is a ring main unit? Why is it suitable for general residential high-voltage power supply to adopt ring main unit power supply?

Why is it called a ring main unit:

In industrial and mining enterprises, residential areas, ports and high-rise buildings and other AC 10kv power distribution systems, due to the small load capacity, the high pressure circuit is usually controlled by load switches or vacuum circuit breakers, and is equipped with high-voltage fuse protection circuits. This system usually uses Ring main unit power supply, so the use of high-voltage switchgear is generally called ring main unit.

In addition to supplying power to the distribution station, the high-voltage bus of the ring main unit must also pass through the current through the ring power supply. Therefore, the high-voltage bus interface of the ring main unit should be selected according to the sum of the load current of the distribution station and the through current of the ring main unit. , To ensure that the high-voltage bus does not run under load during operation.

Applicable places and advantages of ring main unit:

The ring main unit is a set of high-voltage switchgear installed in a steel plate metal cabinet or made into an assembling interval type ring power supply unit. Its core part uses load switches and fuses. It has simple structure, small size, low price, Improve power supply parameters and performance and power supply safety and other advantages.

Ring main unit are widely used in power distribution stations and box-type substations in load centers such as urban residential communities, high-rise buildings, large public buildings, factories and enterprises.

The structure of the ring main unit:

Ring network cabinets are generally divided into two types: air insulation and SF6 gas insulation, which are used for switching load current, breaking short-circuit current and transformer no-load current. Acting as a charging current for overhead lines and cable lines at a certain distance, it plays a role of control and protection. It is an important switchgear for ring power supply and terminal power supply. The cabinet will be equipped with air-insulated load switches.