For example, vacuum cleaner, hair dryers, blenders, electric razors and other appliances with commutator motors, in the operation of the motor and in the contact between the brush and commutator, will produce sparks and then bring electromagnetic interference;

rice cookers, electric irons, oven, washing machines produce electromagnetic interference due to frequent switch on-off action;

the start of air conditioner requiring strong current will lead network voltage temporarily decline;

motors and other inductive loads will lower the power factor when starting; power electric device in variable frequency air conditioner will produce harmonics; 

multi-functional controller in fans has silicon controlled rectifier and will produce higher harmonic disturbance;

appliances with remote control, automatic washing machine, electric kettle, microwave, and other appliances with microprocessor, by use of II level digital signal will cause electromagnetic interference, and with clock frequency of constantly increasing, its electromagnetic disturbance can up to hundreds of MHz;

electromagnetic energy leak of microwave and electromagnetic oven not only will caused electromagnetic disturbance, but also will do harm to human health.