Emission: IEC 61000-3-2. Goal: limitation of harmonic components of the input
current impressed on the public low-voltage supply system, for equipment.
Electromagnetic Compatibility (EMC) Low-Frequency Standards Summary IEC 61000-3-2: Limits for harmonic current emissions (equipment input current ≤ 16A per phase) IEC 61000-3-4: Limitation of emission of harmonic currents in low-voltage power supply systems for equipment with rated current greater than 16 A per phase
Standards on Low-Frequency Emission: IEC 61000-3-2 Goal: limitation of harmonic components of the input current impressed on the public low-voltage supply system, for equipment with input current ≤ 16 A per phase • Equipment to be connected to 220/380 V, 230/400 V and 240/415 V systems operating at 50 Hz or 60 Hz • No limits for systems with nominal voltage less than 220 V (line-to-neutral) • Four categories of equipment • Absolute and/or relative limits (relative limits based on input power)
Page 1
IEC 61000-3-2: Measurement Circuit Three-phase equipment M M
G
In
G
ZS
G
ZS
S
U
EUT
ZS
ZM
ZS
G
ZS
L1 L2 L3 N
In ZM
In U ZM
In ZM ZM
S
IEC 61000-3-2 Supply Source Requirements Test voltage U at the EUT’s terminals: • rated voltage of the equipment. In the case of voltage range, use 230/400 V for single-phase and three-phase supply • voltage accuracy within ± 2 % of the nominal value • frequency accuracy within ± 0.5 % of the nominal value • displacement accuracy between each pair of phases of a three-phase source within ± 1.5° • peak value of the test voltage shall be within 1.40 and 1.42 times its RMS value and shall be reached within 87° to 93° after the zero crossing (not applicable to class A and B equipment)
Page 2
EUT
Single-phase equipment
IEC 61000-3-2 Supply Source Requirements With EUT connected, the harmonic ratios of test voltage shall not exceed:
Limits 0,9% 0,4% 0,3% 0,2% 0,2% 0,1%
Harmonic order 3 5 7 9 even, from 2 to 10 from 11 to 40
Voltage drop on input impedance ZM shall not exceed 0.15V peak
IEC 61000-3-2 Measurement Equipment Requirements • Any type of wave analyzer may be used – (frequency-domain instrumentation using selective amplifier, heterodyne, multiple passive filters, spectrum analyzer tuned to the frequency to be measured, and timedomain instrumentation using digital filters or DiscreteFourier-Transform DFT)
• Annex B of IEC 61000-3-2 reports requirements for measurement equipment
Page 3
IEC 61000-3-2 Classification of Equipment • Class A: balanced 3-phase equipment (r.m.s. line currents differing less than 20 %) and all other equipment, except those in the following classes • Class B: portable tools • Class C: lighting equipment including dimming devices with active input power above 25 W • Class D: equipment having an input current with a "special wave shape" and a fundamental active input power between 75 and 600 W. Whatever the wave shape of their input current, Class B, Class C, and provisionally motor-driven equipment are not considered as Class D equipment
IEC 61000-3-2 Class D equipment: Special Wave Shape
Each half cycle of input current is within the envelope for at least 95% of the time
Page 4
Classification of Equipment Class B
Class C
yes Bal. 3-phase equipment?
no
yes
Portable tool?
no
Lighting equipment?
yes
no no
Class A
Special waveshape (P≤ ≤600W)?
yes Class D
no
Motor driven?
yes
IEC 61000-3-2 - Harmonic Limits Class A and Class B Harmonic order n
Class A max permissible harmonic current A
Class B max permissible harmonic current A
Odd harmonics 3 5 7 9 11 13 15
