Isolating switch is a switching device mainly used for isolating power supply, switching operations, connecting and cutting off small current circuits, without arc extinguishing function. When the isolating switch is in the divided position, there is an insulation distance between the contacts that meets the specified requirements and a clear disconnection mark; below we mainly introduce the characteristics and types of isolating switches.
1. When overhauling electrical equipment, it is necessary to provide an electrical interval and a clearly visible disconnection point to protect the personal safety of maintenance personnel.
2. Isolation switch can not be operated with load, it can not be operated with rated load or large load, can not divide load current and short circuit current, but with arc extinguishing chamber can operate with small load and no-load circuit.
3. In general power transmission operation, close the isolation switch first, then close the circuit breaker or load switch; when the power is off, first open the circuit breaker or load switch, and then disconnect the isolation switch.
4. The selection is the same as other electrical equipment, and its rated voltage, rated current, dynamic stability current, thermal stability current, etc. must all meet the needs of the use occasion.
The role of the isolating switch is to break the circuit of the no-load current. The equipment to be repaired has a clear disconnection point with the power supply to ensure the safety of the maintenance personnel. The isolating switch cannot cut off the load current and short-circuit current without a special arc extinguishing device. Therefore, the isolating switch can only be operated when the circuit is opened by the circuit breaker.
1. According to the different installation methods, it can be divided into outdoor isolating switch and indoor high voltage isolating switch. Outdoor isolation switch refers to an isolation switch that can withstand the effects of wind, rain, snow, pollution, condensation, ice and heavy frost, etc., and is suitable for installation on a terrace.
2. When performing maintenance on electrical equipment, it is necessary to cut off the power supply to separate the maintenance part from the live part and maintain an effective isolation distance. It is required to withstand the withstand voltage level of the overvoltage between the breaks. The knife switch is used as a switch electrical appliance to isolate the power supply.
3. According to the different structure of its insulation pillar. It can be divided into single-column disconnector, double-column disconnector, three-column disconnector. Among them, the single-column isolating switch directly uses the vertical space as the electrical insulation of the break below the overhead bus. Therefore, it has the obvious advantages of saving floor space, reducing the lead wires, and the state of opening and closing is particularly clear. In the case of ultra-high voltage transmission, the single-column disconnector used in the substation has a more significant effect of saving floor space.
If this article is helpful to you, please forward it to more people in need.