Top 5 EN50155 Compliance Requirements for Railway Applications

Railway applications present some of the most unique and challenging industrial automation solutions because the impact of harsh environmental factors and movability on the equipment must always be considered. The EN50155 is an international standard used to monitor these elements, as well as the electronic equipment’s humidity levels, temperature, vibration, shock, and other specifications for use on rolling stock to make it as durable as possible.

Here are the top 5 most noteworthy requirements to be aware of:

  1. Ambient Temperature
    Under EN50155, any solution (for Input/Output, Communications, Human Machine Interface, etc.) must be able to remain at a temperature between -40°C to +85°C (-40°F to 185°F) for a minimum of 10 minutes at the time of start-up. In addition, power supplies in these entities must function with at least 85% efficiency and have a large range of load variance and voltage input. Temperature management is crucial because varying temperatures can be extreme in certain locations throughout the day.
  2. Shock & Vibration
    This requirement concerns the tolerance levels permitted for power supplies that are mounted by body, bogie, and axle to the railcar. The specifications will fluctuate.

    • Minimum: As few as < 1g vibration and 5g shock for power supplies that are body-mounted.
    • Maximum: Up to 30g for 5 hours with 1km/s shock for axle-mounted supplies.

The ability to withstand resonance and be mechanically intact are the most important factors for this requirement.

3. Power Supply Input Voltage
EN50155 calls for minimum voltages of 24, 48, 72, 96 and 110V DC. Power supplies used for railway applications must function within 0.6 and 1.4 nominal with no deviation. This guarantees that each railcar can operate successfully. It’s also beneficial to use an input capacitor to assist with leveling out any ripple voltage to establish more DC input consistency.

4. Performance & Reliability
Safety and quality are extremely valuable factors to consider when it comes to attaining EN50155 certification. Evaluate and adjust elements such as wiring, fault protection, layout, components, and connectors for the power supply in each unit.

5. Approval Testing
Required type testing involves the following factors:

  • performance
  • visual inspection
  • dry heat
  • low temperature operation
  • successful operation over the full input voltage range
  • electrostatic discharge
  • surge
  • transient
  • electrical insulation
  • vibration
  • bump
  • shock


Additionally, an electromagnetic compatibility (EMC) test is typically mandatory with further requirements for end-user and internal testing approval prior to First Article Inspection Approval.

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Amanda DeRoo is one of our ‘Edu-Techies’ and specializes in digital content creation.  Her passions include SEO and her pets (any animals for that matter).  She can be reached at:

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