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A few days ago, a batch of 1000 electric chain saws in Jiaxing were imported from France and returned because the safety regulation test item “electromagnetic compatibility test” failed.

Electromagnetic compatibility (EMC) refers to the ability of equipment or system to operate in accordance with the requirements in its electromagnetic environment without unbearable electromagnetic interference to any equipment in its environment. Therefore, EMC includes two requirements: on the one hand, the electromagnetic interference (EMI) generated by the equipment to the environment during normal operation cannot exceed a certain limit; on the other hand, the appliance has a certain degree of immunity to the electromagnetic interference in the environment, that is, electromagneticsusceptability (EMS).