Select Page


IEC/EN 50121-4 EMC Testing of Railway Signaling and Telecommunication Equipment

The IEC 50121-4 test standard applies to signaling and telecommunication apparatus which is installed in the railway environment. The signaling and telecommunication apparatus mounted in vehicles is covered by EN 50121-3-2.

IEC 50121-4 EMC testing specifies limits for emission and immunity and provides performance criteria for specific signaling and telecommunications equipment. This applies to equipment that may interfere with other apparatus in the railway environment. It also applies to equipment that may increase the total emissions for the railway environment beyond the limits defined in the appropriate standard. When this occurs, it may cause Electro-Magnetic Interference (EMI) to apparatus outside the railway system.

Equipment that complies with the emission levels of EN 61000-6-4 will meet the emission requirements of IEC 50121-4 EMC/EMI testing. This is true as long as the emissions from any d.c. power port is within the emissions limits specified for a.c. power ports. The immunity levels of EN 61000-6-2 will also be adequate except for special cases. IEC 50121-4 EMC testing provides the immunity requirements for such equipment.

The immunity levels given for the apparatus will in most cases allow the apparatus to perform as intended in the railway environment. The immunity level establishes a common reference for evaluating the performance of the apparatus when subject to interference resulting from direct exposure of the apparatus and associated cables to a radio frequency field, or by coupling of the interference from a remote source.

It is important to note that if a port is intended to transmit or receive for the purpose of radio communication (intentional radiators. e.g. transponder systems), then the emission and immunity limits in this standard at the communication frequency do not apply.

The standard does not specify basic personal safety requirements for devices such as protection against electric shock, unsafe operation, insulation co-ordination and related dielectric tests. Also, the fault conditions of the devices have not been taken into account. The requirements and test methods also apply to telecommunications and signaling data and power lines connected to the equipment under test.

The frequency range considered is from d.c. to 400 GHz. No measurements need to be performed at frequencies where no requirement is specified. For products in the scope of EN 61000-3-2 or EN 61000-3-3, the requirements of those standards apply.

Expert IEC Laboratory Testing of Railway & Telecommunication Equipment

Keystone Compliance provides IEC 50121-4 railway testing in a professional, timely and affordable manner. Our lab features multiple chambers, so lead times on scheduling are never an issue. In addition to EMC/EMI testing, our lab also features mechanical, product safety, wireless, ingress protection and package testing. Regardless of the testing need, Keystone Compliance can provide the solution.

For more information on our capabilities, please contact us. If you are ready to see firsthand why so many companies rely on Keystone Compliance for their IEC 50151-4 testing, please request a quote.