Introduction

With the development of electrical and electronic products toward higher frequency, integration and intelligence, electromagnetic interference generated during equipment operation has become increasingly prominent. Electromagnetic interference is mainly divided into conducted interference and radiated interference. The former propagates through conductors such as power cords and signal lines, while the latter spreads through space in the form of electromagnetic waves. Both types of interference may cause equipment malfunction, communication failure, performance degradation, and even failure to meet market access EMC requirements. To ensure that products comply with domestic and international standards such as GB, CISPR, EN and FCC, a professional EMI Compliance Test Receiver must be used to quantitatively measure and evaluate interference levels.

The LISUN EMI-9K Series EMI Compliance Test Receiver is an integrated solution designed specifically for electromagnetic interference testing of electrical and electronic products. Among them, the EMI-9KB model is widely used in EMI testing of lighting equipment, household appliances, drive power supplies, controllers and other products due to its wide frequency coverage from 9 kHz to 300 MHz, high-precision measurement and CDNE coupling network configuration. This system can perform both conducted disturbance voltage testing and radiated interference testing simultaneously, and automatically generate test reports, providing comprehensive technical support for enterprise R&D self-inspection and third-party laboratory certification.

Working Principle of the EMI Compliance Test Receiver

The core function of an EMI Compliance Test Receiver is to quantitatively collect, analyze and judge electromagnetic noise generated by the equipment under test (EUT) during operation. Conducted interference testing mainly focuses on the frequency band of 9 kHz to 30 MHz. A LISN (Line Impedance Stabilization Network) is used to pick up interference voltage from the power cord, avoiding the influence of grid background noise on measurement results. Radiated interference testing covers frequency bands above 30 MHz, receiving spatial radiation signals through dedicated antennas, CDNE coupling/decoupling networks or absorption clamps, which are then sent to the EMI receiver for spectrum analysis.

The LISUN EMI-9KB EMI Compliance Test Receiver strictly complies with requirements of standards such as CISPR 15 and CISPR 16. It adopts three detection modes: Peak (PK), Quasi-Peak (QP) and Average (AV), which can accurately determine whether the interference level exceeds the standard limit. Through automatic scanning, the system quickly locates interference frequencies and amplitudes, providing intuitive data for engineers to identify interference sources, optimize circuit design, and implement filtering and shielding measures.

System Structure and Technical Features of LISUN EMI-9K Series

3.1 Modular Hardware Configuration

The EMI-9K Series EMI Compliance Test Receiver adopts a modular architecture, mainly composed of an EMI receiver, LISN, CDNE coupling/decoupling network, attenuator, test software and supporting cables. As the main model, the EMI-9KB meets the needs of low-frequency conducted tests and medium-high frequency radiation tests, suitable for most lighting and electronic appliance products. The system can be expanded with accessories such as shielding chambers, three-loop antennas and absorption clamps to further improve test environment consistency and measurement accuracy.

3.2 High-Precision Measurement Performance

This series of EMI Compliance Test Receiver features high frequency resolution, low measurement error and wide level measurement range. It can stably capture weak interference signals and ensure repeatability and consistency of multiple measurements. Its key technical parameters are shown in the table below:

Technical Parameter	EMI-9KA	EMI-9KB	EMI-9KC
Frequency Range	9 kHz ~ 30 MHz	9 kHz ~ 300 MHz	9 kHz ~ 1 GHz
Frequency Stability	1×10⁻⁶	1×10⁻⁶	1×10⁻⁶
Measurement Uncertainty	±2 dB	±2 dB	±2 dB
Detection Modes	PK, QP, AV	PK, QP, AV	PK, QP, AV
Level Range	20 dBμV ~ 140 dBμV	20 dBμV ~ 140 dBμV	20 dBμV ~ 140 dBμV
Available Bandwidths	200 Hz, 9 kHz, 120 kHz	200 Hz, 9 kHz, 120 kHz	200 Hz, 9 kHz, 120 kHz

3.3 Multi-Standard Compatibility and Automatic Testing

The LISUN EMI-9K Series EMI Compliance Test Receiver is fully compatible with domestic and international EMC standards including GB 17743, CISPR 15, EN 55015 and FCC. It especially adapts to latest requirements such as CISPR 15:2018 and AS/NZS CISPR 15:2025. The supporting professional test software supports fully automatic scanning, real-time data display, curve comparison, limit line loading and test report export, greatly reducing operation difficulty and improving testing efficiency.

Application Value of the EMI Compliance Test Receiver

In the product R&D stage, the EMI Compliance Test Receiver helps engineers quickly discover interference problems caused by PCB layout, grounding design, switching frequency and so on, reducing later rectification costs through early optimization. In type testing and certification, quantitative test data provided by the system can be directly used as technical evidence for CE, CCC, FCC and other certifications, ensuring smooth market access.

In production quality control, the system enables batch sampling inspection to timely detect EMI exceeding standards caused by component differences or process fluctuations. By locating interference frequencies and amplitudes, engineers can accurately determine whether interference comes from the power circuit, driver chip, wiring harness or radiation structure, so as to adopt targeted rectification schemes such as magnetic rings, filter capacitors and shielding covers, significantly improving EMC optimization efficiency.

Conclusion

The LISUN EMI-9K Series EMI Compliance Test Receiver, especially the EMI-9KB model, has become important equipment for quantitative measurement of electromagnetic interference in electrical and electronic products with stable and reliable performance, standardized testing procedures and comprehensive standard coverage. The system can perform both conducted interference and radiated interference testing simultaneously, providing complete technical support for EMC compliance testing, interference source location and product design optimization, effectively improving product quality and international market competitiveness.

With the increasingly complex electromagnetic environment and continuous growth of EMI testing demands, this EMI Compliance Test Receiver will play a more important role in fields such as electronics, lighting, power supplies and industrial control, helping enterprises achieve efficient, standardized and reliable EMC testing and product upgrading.

Tags：EMI-9KB