Control of Conducted EMI to Meet Compliance Regulatory Limits of a Household Appliance—A Case Study

Abstract

Conducted Electromagnetic Interference (EMI) is an unwanted signal which gets transmitted on power and signal carrying conductors and travel usual current paths of an equipment. With the increased use of electric/electronic equipment worldwide, conducted EMI and its potential impact on the operational state of equipment have become a very important engineering issue. Often such signals are produced because of inadequate filtering of high frequency currents within the equipment leading to leakage onto the conductors emerging from the equipment. This situation necessities the control of such conducted EMI levels at the design phase of equipment. In this paper, the author intends to highlight non-compliance of conducted EMI levels observed during the evaluation of household appliance as per International standard. Apart from evaluation part, this paper also includes the remedial measures taken in the form of adequate input filtering (by in-house filter design) which finally leads to the compliance of appliance with regulatory limits.

Indexing terms:

• Line impedance stabilization network (LISN)
• Ground reference plane (GRP)
• X-capacitor (Cx)
• Y-capacitor (Cy)

Additional information

Notes on contributors

V K Dhar

Vinod Kumar Dhar is an EMC Scientist working in Ministry of Information Technology for last 15 years, posted at ERTL (W), Mumbai, India. His contributions include setting up EMC laboratory, equipment installations, evaluation of products as per different International Standards, calibration of EMC equipment and upgradation of test facilities. He has been providing consultancies for EMC issues for domestic, commercial, industrial, scientific & medical electronic products including automobile electronics. He has 20 National/International publications on EMC related issues, which are based on practical case studies. Presently he is involved in evaluation of products for CE marking and providing design consultancies to meet EMC requirements of ERTL (W).