- Equipment using switching power supplies, such as Personal Computers, printers, photocopiers, decoders, video equipment, etc.;
- transformers;
- fluorescent lamps;
- incandescent lighting systems controlled by TRIAC;
- variable speed drives (inverter, soft-starter, converter AC/CC e CC/AC, chopper, etc.);
- galvanic systems;
- microwave ovens;
- some medical devices;
- welders, induction ovens and arc furnaces.
- Immunity to harmonics:
- CEI EN 61000-2-2 Electromagnetic compatibility (EMC) - Part 2-2: Environment - Compatibility levels for low-frequency conducted disturbances and signalling in public low-voltage power supply systems.
- Emissions to harmonics:
- CEI EN 61000-3-2: Electromagnetic compatibility (EMC) Part 3-2: Limits - Limits for harmonic current emissions
(equipment input current <= 16 A per phase);
- CEI EN 61000-3-12: Electromagnetic compatibility (EMC) Part 3-12: Limits - Limits for harmonic currents produced by equipment connected to public low-voltage systems with input current > 16 A and ≤ 75 A per phase.
- CEI EN 61000-3-2: Electromagnetic compatibility (EMC) Part 3-2: Limits - Limits for harmonic current emissions
(equipment input current <= 16 A per phase);
- CEI EN 61000-3-3: Electromagnetic compatibility (EMC) - Part 3-3: Limits - Limitation of voltage changes, voltage fluctuations and flicker in public low-voltage supply systems, for equipment with rated current ≤16 A per phase and not subject to conditional connection;
- CEI EN 61000-3-11: Electromagnetic compatibility (EMC) - Part 3-11: Limits - Limitation of voltage changes, voltage fluctuations and flicker in public low-voltage supply systems - Equipment with rated current ≤ 75 A and subject to conditional connection.
Harmonics Measurement
The harmonics are sinusoidal currents equal to an integer multiple of the fundamental frequency of 50 Hz of system distribution, which vary the shape of the current, with consequent reduction of the efficiency of an electrical system, possible damage to the insulators (on the lines and to the users) and the creation of operating anomalies on different components. The harmonics are generated by non-linear loads to be attributed to:The reference standards are for:
Flicker
The "Flicker" is a phenomenon caused by rapid and continuous variations of the current voltage with consequent instability of the brightness of the lamps perceivable to the eye as flicker effect.The reference standards are: