EN 50121-3-2: Ensuring Electromagnetic Compatibility for Railway Rolling Stock
EN 50121-3-2 defines EMC requirements for railway rolling stock, ensuring safe operation, reduced interference, and compliance with international rail standards.

Introduction to EN 50121-3-2
EN 50121-3-2 is part of the European EN 50121 series, defining electromagnetic compatibility (EMC) requirements for railway rolling stock. It ensures that trains and rail vehicles operate without causing or being affected by electromagnetic interference (EMI) in signaling, communication, and traction systems.
Scope and Purpose
The standard applies to all types of railway vehicles, including passenger coaches, freight wagons, and high-speed trains. It covers the measurement, limits, and testing procedures for conducted and radiated emissions, immunity to electromagnetic disturbances, and overall EMC compliance.
Key Components
- Emission Limits: Defines maximum levels of conducted and radiated emissions from rolling stock equipment.
- Immunity Requirements: Specifies the ability of rolling stock to resist external electromagnetic disturbances without functional degradation.
- Testing Procedures: Standardizes laboratory and on-track EMC tests for compliance verification.
- Documentation: Requires detailed EMC test reports and maintenance procedures to ensure ongoing compliance.
Comparison Table
| Parameter | EN 50121-3-2 Requirement | Typical Practice |
|---|---|---|
| Radiated Emission Limit | 30 MHz – 1 GHz: ≤ 80 dBµV/m | 85 dBµV/m |
| Conducted Emission Limit | 0.15 – 30 MHz: ≤ 79 dBµV | 85 dBµV |
| Immunity Test Voltage | 1 kV for power lines | 0.5 kV |
Implementation and Benefits
EN 50121-3-2 is adopted by rail operators and rolling stock manufacturers to ensure EMC compliance, prevent operational disturbances, and maintain safe and reliable train services. Its implementation reduces risks of signaling interference, improves passenger safety, and ensures compatibility across international rail networks.
Snippet Bait
EN 50121-3-2 sets EMC requirements for railway rolling stock, ensuring vehicles operate safely, avoid interference, and comply with international electromagnetic standards.




