This European Standard applies to emission and immunity aspects of EMC for electrical and electronic 
apparatus and systems intended for use in railway fixed installations for power supply. This includes 
the power feed to the apparatus, the apparatus itself with its protective control circuits, trackside items 
such as switching stations, power autotransformers, booster transformers, substation power 
switchgear and power switchgear to other longitudinal and local supplies. 
Filters operating at railway system voltage (for example, for harmonic suppression or power factor 
correction) are not included in this standard since each site has special requirements. Filters would 
normally have separate enclosures with separate rules for access. If electromagnetic limits are 
required, these will appear in the specification for the equipment. 
If a port is intended to transmit or receive for the purpose of radio communication (intentional radiators, 
e.g. transponder systems), then the radiated emission requirement in this standard are not intended to 
be applicable to the intentional transmission from a radio-transmitter as defined by the ITU. 
The frequency range considered is from DC to 400 GHz. No measurements need to be performed at 
frequencies where no requirement is specified. 
Emission and immunity limits are given for items of apparatus which are situated: 
a) within the boundary of a substation which delivers electric power to a railway; 
b) beside the track for the purpose of controlling or regulating the railway power supply, including 
power factor correction; 
c) along the track for the purpose of supplying electrical power to the railway other than by means of 
the conductors used for contact current collection, and associated return conductors. Included are 
high voltage feeder systems within the boundary of the railway which supply substations at which 
the voltage is reduced to the railway system voltage; 
d) beside the track for controlling or regulating electric power supplies to ancillary railway uses. This 
category includes power supplies to marshalling yards, maintenance depots and stations; 
e) various other non-traction power supplies from railway sources which are shared with railway 
traction. 
The immunity levels given in this standard apply for: 
- vital equipment such as protection devices; 
- equipment having connections to the traction power conductors; 
- apparatus inside the 3 m zone; 
- ports of apparatus inside the 10 m zone with connection inside the 3 m zone; 
- ports of apparatus inside the 10 m zone with cable length > 30 m. 
Apparatus and systems which are in an environment which can be described as residential, 
commercial or light industry, even when placed within the physical boundary of the railway substation, 
shall comply with EN 61000-6-1:2007 for immunity and EN 61000-6-3:2007 for emission requirements. 
Excluded from the immunity requirements of this standard is power supply apparatus which is 
intrinsically immune to the tests defined in Tables 1 to 6. 
NOTE An example is an 18 MVA 230 kV to 25 kV power supply transformer. 
These specific provisions are to be used in conjunction with the general provisions in EN 50121-1. 
This part of the standard covers requirements for both apparatus and fixed installations. The sections 
for fixed installations are not relevant for CE marking.
NOTE: If the word "harmonized" (marked in green) is not found in the field with the name of the directive, it means that the European standard is not cited in the OJEU.
Directive 2014/30/EU of the European Parliament and of the Council of 26 February 2014 on the harmonisation of the laws of the Member States relating to electromagnetic compatibility (recast)
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