What Is A High And Low Voltage Complete Set Of Equipment?

What is a high and low voltage complete set of equipment?

High and low voltage complete equipment is an important equipment used in power systems.

一. Components

High and low voltage complete equipment is mainly composed of high voltage switchgear, low voltage switchgear, transformer, etc.

1.  High voltage switchgear: used to control and protect high voltage circuits, usually including circuit breakers, disconnectors, load switches, transformers and other components.
2.  Low voltage switchgear: used to control and distribute low voltage circuits, including air switches, contactors, relays and other electrical components.
3. Transformer: used to change the voltage level, convert high voltage electricity into low voltage electricity or boost low voltage electricity to high voltage electricity.

二. Function

1. Power distribution: realize the reasonable distribution of electric energy, distribute high voltage power to various power consumption areas, and then distribute electric energy to different power consumption equipment through low voltage switchgear.
2.  Control and protection: control and protect the power system. When a circuit fails, such as short circuit, overload, etc., the protection device in the complete equipment will act quickly to cut off the faulty circuit and protect the safety of equipment and personnel.
3. Improve power supply reliability: through reasonable design and configuration, ensure the stable operation of the power system and reduce the occurrence of power outages.

三. Application fields

Widely used in various fields such as industry, commerce, and civil use, such as factories, shopping malls, hospitals, residential areas, etc. It plays a vital role in the power generation, transmission, transformation, and distribution of the power system.

四. Common faults and treatment methods

(I) High-voltage switch cabinet failure

1. The circuit breaker refuses to open or close: the possible reasons are control circuit disconnection, abnormal operating power supply voltage, circuit breaker mechanical jamming, etc. When handling, first check whether the control circuit wiring is loose or detached, and measure whether the operating power supply voltage meets the standard; if it is a mechanical failure, the circuit breaker needs to be disassembled and inspected, the jammed parts need to be cleaned, and damaged parts need to be replaced if necessary.
2. Poor contact of the isolating switch: usually caused by oxidation of the contact, uneven surface, or insufficient contact pressure. The oxide on the contact surface can be polished and the contact pressure spring can be adjusted to ensure good contact of the contact. In severe cases, the isolating switch contacts need to be replaced.

(II) Low-voltage switch cabinet failure

1. Air switch tripping: Overload, short circuit or air switch failure may cause tripping. If it is due to overload, it is necessary to check the electrical equipment and distribute the load reasonably; if it is short circuit, it is necessary to check whether the line has insulation damage, internal short circuit of the equipment, etc., and repair the fault point before reclosing; if the air switch is aging and damaged, it needs to be replaced in time.
2. Abnormal contactor attraction: manifested as contactor failure to attract, abnormal sound after attraction, etc. Failure to attract may be caused by coil disconnection or control circuit failure; abnormal attraction sound may be caused by poor contact of the contactor or foreign matter on the surface of the iron core. According to different reasons, check the coil, repair the control circuit, clean the surface of the iron core or replace the contactor contact.