Structural characteristics of high voltage load switch

High voltage load switch is a kind of high voltage electrical equipment specially used to turn on and off load current. When the release is installed, it can also trip automatically under overload. However, it has only a simple fire extinguishing device, so it can not cut off the short-circuit current. In most cases, the load switch is connected in series with the high-voltage fuse to cut off the short-circuit current with the help of the fuse. It is divided into indoor and outdoor. For example, the appearance of indoor air pressure high-voltage load switch is very similar to that of disconnector. With arc extinguishing device, etc

What is the difference between high voltage load switch and disconnector?

Disconnector is a kind of switchgear without arc extinguishing device. It is mainly used to disconnect the circuit without load current and isolate the power supply. There is an obvious disconnection point in the opening state to ensure the safe maintenance of other electrical equipment. It can reliably pass through normal load current and short-circuit fault current in closing state. It can't cut off the arc current because there is no special arc extinguishing device. Therefore, the disconnector can only be operated when the circuit has been disconnected by the circuit breaker. It is strictly prohibited to operate with load, so as to avoid serious equipment and personal accidents. Only voltage transformers, lightning arresters, no-load transformers with excitation current not exceeding 2a and no-load lines with current not exceeding 5A can be operated directly with disconnectors.

Load switch is a kind of switching appliance between circuit breaker and disconnector. It has a simple arc extinguishing device, which can cut off the rated load current and a certain overload current, but can not cut off the short-circuit current

How to select the size of high voltage load switch?

The selection of high voltage load switch is basically the same as that of circuit breaker. It must meet the five conditions of rated voltage, rated current, breaking current, limit current and thermal stability.