How does AFR series arc flash relay work?

Accidents of severely burning switchgear caused by arc short-circuit faults of switchgear are increasing, and accidents of main transformers being damaged by external short-circuit current impacts are also increasing year by year. At present, in foreign power systems, especially power plants, about 70% -80% of newly-built power plants have adopted special busbar arc protection; in order to ensure the safe operation of transformers and busbar switchgear, according to the requirements of rapid relay protection, there is an urgent need Configure special medium and low voltage busbar protection. AFR series arc protection system, as a new generation of fast busbar protection devices, has attracted more and more attention from various industries. Compared with traditional busbar protection, its protection action is fast and its reliability is high, so as to ensure the safety of operators, minimize the loss of failure, and create conditions for quick handling of failure and restoration of power supply.

The arc protection action criterion is that two conditions need to be generated when a fault occurs: arc light and overcurrent. When arc light and current increase are detected at the same time, a trip command is issued; when only arc light or current increase is detected, an alarm signal is issued, and no trip command is issued.