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EN 50121 General Railway Electromagnetic Compatibility Testing Requirements

EN 50121 provides a means of prescribing compatibility between internal parts and railway systems. As a certified environmental lab, we realize the importance of compliance EN 50121 testing. Meeting the environmental EN 50121 requirements can be difficult. We understand the challenges and guide companies through the process.

Keystone Compliance’s proven process helps avoid product launch delays. Our accurate test reports are delivered quickly and we are in constant communication throughout the entire test process. When products do not meet the requirements, we assist with finding solutions. Keystone provides the peace of mind that all of your needs will be met. 

Request a quote and find out first hand about our competitive pricing, timely process, and outstanding reputation. Contact us to receive more information on environmental lab testing.

Summary of EN 50121 Environmental Railway Applications testing

The EN 50121-1 compliance testing standard outlines the structure of all EN 50121 testing methods. Phenomena excluded from this type of testing are Nuclear EM pulse, abnormal operating conditions, and the induction effects of a direct lightning strike.

Emission limits at the railway system boundary do not apply to intentional transmitters. Furthermore, safety considerations and the biological effects of non-ionizing radiation, as well as apparatus for medical equipment, are not considered in this standard.

Scope of EN 50121 Railway System Environmental Testing

For operating purposes, railway systems use electrical that require high outputs and power electronic systems. These outputs may be up to several MVA. In an electric railway system, the trains are supplied by means of sliding contacts from a power supply line. This is called the catenary system or overhead contact line. 

The current generally returns to the substation via rails. The railway system is an integrated system in which electricity has many other uses in addition to train propulsion. This includes:

  • Heating, air conditioning catering, and light passenger coaches with converters on the vehicles.
  • Signaling and telecommunication systems along the track and between control centers.
  • Computer installations in control centers, linked via trackside routes.
  • Passenger information systems on vehicles, stations, and depots.
  • Traction within diesel-electric locomotives and multiple units.
  • Battery traction vehicles.

Problems arise not only within locomotives and the power supply. Non-electrified traction such as diesel-electric traction may also be a source of EM noise. The normal and distributed working of these systems may be a source of electromagnetic noise which can influence all other systems.

There are five distinguished modes of coupling. The coupling between systems is by well-known phenomena and limits are expressed in terms of these phenomena. The five modes include:

  • Electrostatic coupling
  • Capacitive coupling
  • Inductive coupling
  • Conductive coupling
  • Electric and magnetic radiation

Lastly, there are many various differences between electric railway systems and other large electric networks. These include but are not limited to:

  • A wide variety of power supply configurations
  • A wide variety of power use and control systems and subsystems
  • The use of sliding contacts to convey high powers to the moving trains
  • The high speed of some trains
  • The presence of several moving sources within the same zone of influence
  • High single-phase loads which may cause an imbalance in the three-phase system
  • The possibility of simultaneous generation of disturbance from several sources

Keystone Compliance Provides Expert EN 50121 Testing

Keystone has a full lab of test equipment which permits us to provide short lead times on scheduling. In addition to environmental testing, Keystone has a detailed scope of expertise including freeze-thaw, humidity, sand and dust, and rain. Our team strives to give our customers more time and energy on product development instead of testing. 

Contact us to receive more information on railway environment testing. Request a quote to learn why we are one of the fastest-growing environmental compliance test labs in the country.