Research on Application of EFT Pulse Generator in EMC Immunity Test

Introduction

In fields including industrial control, automotive electronics, consumer electronics, medical devices and communication equipment, electrical and electronic equipment is frequently subjected to interference caused by power grid switching, on-off of inductive loads and relay contact bounce. These disturbances form electrical fast transient bursts (EFT) characterized by steep rising edges, high repetition frequency and short duration. Such interference may lead to equipment crash, reset, data error and control failure, which seriously threaten system reliability and operational safety.

EMC immunity test is a mandatory procedure for product certification and finalization, and the EFT pulse generator is the dedicated standard equipment for this test. LISUN EFT61000-4 EFT pulse generator is professionally developed for EMC immunity tests. It is pre-installed with standard programs complying with GB/T 17626.4, IEC/EN 61000-4-4 and other standards. Featuring accurate output waveform, wide adjustable parameter range and intelligent operation, it is widely used for EMC testing and certification of various electrical and electronic products . This paper conducts a systematic analysis on this EFT pulse generator and demonstrates its core value in modern EMC test systems.

Working Principle and Core Functions of EFT Pulse Generator

Based on high-voltage pulse shaping and precise timing control technology, the EFT pulse generator simulates actual fast transient disturbances, applies standard-specified burst interference to the equipment under test, and judges whether the device maintains normal functions.

Basic Working Principle
The device generates narrow pulses with a rising edge of approximately 5 ns and a pulse width of approximately 50 ns through high-voltage charging, rapid discharging and pulse shaping circuits. These pulses are grouped into pulse trains at a set frequency and output in the form of periodic burst pulses. The interference is applied to power ports and signal ports via Coupling/Decoupling Network (CDN) or coupling clamps to simulate actual conductive coupling paths and fully assess the equipment immunity.

EFT61000-4_EFT Tester

Core Functions of LISUN EFT61000-4 EFT Pulse Generator
•  Standard Waveform Output: It fully complies with IEC/EN 61000-4-4 and GB/T 17626.4. The pulse rising edge is 5 ns ±30%, and the pulse width is 50 ns ±30% under 50 Ω load. The pulse frequency is continuously adjustable from 1 kHz to 1000 kHz, with positive, negative and automatic alternating polarities, ensuring the test conditions are fully compliant with relevant standards.
• Wide-range Parameter Adjustment: The output voltage covers multiple ranges from 0 to 5 kV / 6 kV. The pulse train length ranges from 0.01 ms to 20 ms, the burst period from 100 ms to 500 ms, and the test duration from 1 s to 9999 s. It supports custom mode and one-key call of standard levels, adapting to full-scenario tests from civil products to industrial high-severity applications.
•  Intelligent Touch Operation: Equipped with a large-size Chinese and English Android touch screen, the interface is intuitive and easy to operate. Built-in standard test programs allow quick parameter calling, configuration saving and data traceability, effectively reducing manual operation errors.
• Complete Coupling Adaptation: It supports built-in and external three-phase five-wire Coupling/Decoupling Networks with current specifications of 16 A, 32 A and 100 A. It can be matched with capacitive coupling clamps, calibration kits and standard test tables to quickly build a fully compliant test system.
• High Safety and Stability: Adopting modular design and multi-protection mechanism, the equipment runs stably for long-term continuous operation with excellent waveform consistency, meeting the requirements of high-frequency testing in laboratories and production lines.

Technical Parameters of LISUN EFT61000-4 Series EFT Pulse Generator

With modular design, this series of EFT pulse generators covers low-power household appliances to high-power industrial equipment. Users can select models flexibly according to the current and voltage level of the equipment under test to realize multi-purpose use and high-efficiency testing.

Applicable Standards and Test Procedures for EFT Pulse Generator

Main Applicable Standards
LISUN EFT61000-4 EFT pulse generator complies with mainstream domestic and international EMC immunity standards, and the test results are recognized globally:
• GB/T 17626.4-2018, Electromagnetic compatibility — Testing and measurement techniques — Electrical fast transient/burst immunity test
• IEC 61000-4-4:2012, Electromagnetic compatibility (EMC) – Part 4-4: Testing and measurement techniques – Electrical fast transient/burst immunity test
• EN 61000-4-4:2012, European Union harmonized standard
• ANSI/IEEE C62.41-1991, Surge Voltage Specification for Low-Voltage AC Power Circuits

Standard Test Procedures
• Test Preparation: Connect the EFT pulse generator, coupling/decoupling network, equipment under test and monitoring instruments, and arrange grounding and cables in accordance with standards.
• Parameter Configuration: Select standard test levels or customize voltage, frequency, pulse train length, test duration and pulse polarity.
• Interference Application: Apply burst pulses to power ports via coupling network, and test signal lines with coupling clamps for each port one by one.
• Status Monitoring: Observe whether the equipment under test works normally during and after interference application, and record abnormal phenomena.
• Result Judgment: Judge pass or fail according to standards and generate test reports for product optimization or certification application.

Application Value and Industry Scenarios of EFT Pulse Generator

The EFT pulse generator is essential equipment for electrical and electronic products from R&D to market launch, covering the whole industrial chain:
• Product R&D and Optimization: Identify electromagnetic weak points in the design phase, and guide the design of circuit filtering, grounding, shielding and software anti-interference to improve product robustness.
• Quality Control and Factory Inspection: Conduct sampling tests on production lines to verify batch consistency and reduce after-sales failure caused by electromagnetic interference.
• Certification and Market Access: Meet the requirements of mandatory certifications such as CCC, CE, FCC and SRRC, serving as a passport for products to enter domestic and overseas markets.
• Wide Industry Coverage: Consumer Electronics: Immunity test for power and signal ports of mobile phones, chargers, home appliances and smart home devices. Automotive Electronics: Test vehicle controllers, sensors and lamps to adapt to complex on-board electromagnetic environments. Industrial Control: Verify the operational stability of PLCs, frequency converters and servo systems under strong interference. Medical Devices: Ensure the functional reliability and safety of monitors and diagnostic equipment. Communication Equipment: Test base stations, switches and routers against transient interference.

Actual tests show that for products optimized and verified by EFT pulse generators, the failure rate related to electromagnetic interference can be reduced by more than 60%, which greatly enhances brand competitiveness and user satisfaction.

Conclusion and Prospect

The EFT pulse generator is an indispensable key device for EMC immunity tests. It can accurately simulate on-site electrical fast transient burst interference and scientifically evaluate the operational stability of equipment in complex electromagnetic environments. Featuring standard compliance, high parameter accuracy, intelligent operation and flexible configuration, LISUN EFT61000-4 EFT pulse generator has become a mainstream choice in the EMC test industry.

With the upgrading of intelligent and high-power equipment, as well as the growing demand for high-reliability scenarios including automotive, medical and industrial fields, EFT pulse generators will develop towards higher voltage, larger current, fully automatic testing, multi-function integration, remote calibration and cloud data management. EFT pulse generators will continue to guarantee the electromagnetic safety of products and promote the development of electrical and electronic industries towards higher reliability and safety.