Inter laboratory comparison (ILC) of conducted emission measurements

Abstract

This paper presents a comprehensive Inter Laboratory Comparison (ILC) of conducted emission measurements as per CISPR 22. The proposed ILC, an important requirement of International Standard ISO/IEC 17025 as part of Quality Assurance is accomplished by utilizing Comparison Noise Emitter (CNE III) source (150 kHz-30 MHz) which is widely used for ILC measurements of EMC Tests facilities. The ILC for five NABL (National Accreditation Board for Testing and Calibration Laboratories) accredited EMC laboratories in India is presented. The measurements data are presented in peak and average detection modes over the frequency range of interest under controlled environment. The measured emission is in the range of 65 dBμV to 80 dBμV. Z-score is calculated for all the laboratories over 0.165 MHz-30MHz range using Classical Method as well as Robust Method. The measurements at all 5 EMC laboratories exhibited a Z-score ≤ 2. This paper intends to report that the performance evaluation of participant Laboratories can be done using either by Classical Method or Robust method. A comparative analysis is presented for all the measured data for both Classical and Robust methods.