Q.Are the power supply EMC filters effective as a countermeasure against power line harmonics?
EMC Components > EMC Components > Power Line EMC Filters
A. Countermeasures against power line harmonics targets frequencies up to 40th wave (2.4kHz) of the fundamental wave. For this, several mH inductance is necessary for the power supply line (differential mode). However, power supply EMC filters are designed for countermeasures against 150kHz to 30MHz frequencies, and the inductance components in differential mode are of several 10μH. Therefore, power supply EMC filters are not so effective as a countermeasure against power line harmonics.