As long as the electric equipment has arc, arc protection can be used. At present, arc protection is mainly used in medium voltage bus system and switch cabinet as bus or feeder protection. Its function and effect are completely equal to and superior to the existing bus protection of various principles, which can protect the whole bus.

Arc light is usually caused by the electric equipment in the process of long-distance travel due to over-voltage and poor insulation coordination caused by the air breakdown process of arc light phenomenon, as well as the high temperature caused by arc light phenomenon caused by combustion, explosive pressure. If it is not removed in time or effective protective measures are taken, the insulation damage of electrical equipment may be caused in small scale, and the operation of the equipment can not be verified. In large scale, it may cause personal injury and death accidents, explosion accidents caused by arc light of electrical equipment in flammable environment, and burning accidents of adjacent equipment.

The switch cabinet is more likely to cause arc discharge due to compact components, narrow space, insufficient creepage distance, poor operating conditions and easy to be polluted by dust. The arc protection device can be selected to improve the reliability combined with traditional protection.

In the same way, the box type substation has a narrow space, and the layout of various electrical components is relatively compact, which is also prone to arc short circuit accidents. Therefore, the arc protection system can be installed in the box type substation to further improve the overall safety of the box type substation.

The outlet of arc protection can be used for direct trip, and can also be used to send alarm signal independently. It can be set and selected according to the field operation and working conditions.