Views: 0 Author: Site Editor Publish Time: 2021-12-30 Origin: Site
The emergence of the Earthing Switch replaces the portable ground wire, which grounds the equipment during high-voltage equipment and line maintenance to protect personal safety.
What are the characteristics of Earthing Switch?
What is the function of Earthing Switch?
What role does Earthing Switch play in the power distribution cabinet?
1. According to the structure of the Earthing Switch, it can be divided into two types: open type and closed type. The conductive system of the former is exposed to the Earthing Switch like an isolating switch in the atmosphere, and the conductive system of the latter is enclosed in SF charging. Or oil and other insulating media.
2. Earthing Switch needs to close short-circuit current, and must have a certain short-circuit closing capacity and dynamic and thermal stability. But it does not need to break load current and short-circuit current, so there is no arc extinguishing device. The lower end of the knife is usually connected to the grounding point through a current transformer. The current transformer can give a signal for relay protection.
3. The Earthing Switches of various structures are divided into unipolar, bipolar and tripolar. Single pole is only used for neutral point grounding system, while bipolar and three pole are used for neutral point ungrounded system, sharing an operating mechanism for operation.
(1) Normal working grounding during line maintenance. When the circuit where the circuit breaker is located needs to be overhauled, the circuit breaker is in the open position, and the isolating switches on both sides are open and in the open state. The Earthing Switch is closed for normal working grounding. To ensure the safety of equipment and maintenance personnel.
(2) Suitable for static electricity and electromagnetic induction current. In two or more overhead transmission lines that share towers or are arranged in parallel adjacent to each other, when one or several lines are out of power, electromagnetic induction and electrostatic induction are generated between it and adjacent live lines. Generate induced voltage and induced current. Therefore, it is used as a Earthing Switch for this type of circuit.
(3) Close short-circuit current. The Earthing Switch with rated short-circuit making current should be able to be closed at any applied voltage including its rated voltage and any current including its rated short-circuit making current. The rated short-circuit making current of the Earthing Switch is equal to the rated peak withstand current.
The Earthing Switch in the power distribution cabinet plays a role in ensuring the personal safety of maintenance personnel. Since the power distribution cabinet is a live device, in order to ensure that the power supply side or load side of the power distribution cabinet does not intrude into the power supply during maintenance, an Earthing Switch is installed on the power distribution cabinet. The location of the Earthing Switch is determined by the direction of the possible incoming calls from the power distribution cabinet. Some are set on the bus bar, and the bus bar is closed during maintenance. Even if there is a malfunction outside to send electricity to the bus bar, it will not endanger personal safety because the bus bar is grounded. It is also installed on the bus side of the circuit breaker, and its function is the same as above. It is also installed on the load side of the circuit breaker. This is because there is also a power supply on the load side. The power supply may also be introduced due to malfunction during maintenance. Therefore, a Earthing Switch is also installed to ensure safety.
For more information about Earthing Switch, please contact Zhejiang Zhegui Electric Co., Ltd has committed to providing the increasing of Earthing Switch, and make them more effective, reliable, and consistence.