Main electromagnetic interference source of household appliances
forms commutator motor operate producing sparks or from actions of
mechanical switches, kinds of controllers and protectors. 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.
CISPR 14-1 and CISPR 14-2 are major standards of electromagnetic
compatibility for household appliances. But microwave and
electromagnetic oven (household electromagnetic induction
appliances) belong to group 2 class B equipment of industrial,
scientific and medical (ISM) equipment , so their electromagnetic
interference standard shall comply with the regulations of CISPR
11. In EU, the corresponding EMC standards for household appliances
are EN 55014-1 and EN 55014-2, but the standard of microwave and
cooker is EN55011.
In the US market, common household appliances belong to
unintentional emission device (Unintentional RF Equipment) under
regulations of FCC Part 15, requires the way of verification to
acquire FCC approval. Similarly, microwave and electromagnetic oven
belonging to ISM equipment need to comply with the regulations of
FCC Part 18. As for certification mode, choosing Declaration of
Conformity (DOC) or Certification is required.
CISPR 14-1/EN 55014-1 emission of household appliance and electric
tools
CISPR 14-2/EN 55014-2 immunity to electromagnetic interference of
household appliance and
electric tools
CISPR 11/EN 55011 radio-frequency disturbance of industrial,
scientific and
medical(ISM)equipment
EN61000-3-2 harmonic current
EN61000-3-3 limitation of voltage changes, voltage fluctuations and
flicker
IEC/EN61000-4-2 electrostatic discharge
IEC/EN61000-4-3 radio frequency and electromagnetic field
IEC/EN61000-4-4 electrical fast transient and burst
IEC/EN61000-4-5 surge
IEC/EN61000-4-6 immunity to conducted disturbance, induced by
radio-frequency fields
IEC/EN61000-4-11 voltage dip and short interruption
FCC Part 15 device of unintentional radiators and intentional
radiators
FCC Part 18 industrial, scientific and medical equipment
