International Standards and Conformity Assessment for all electrical, electronic and related technologies



Reference EN 50522:2010
Title Earthing of power installations exceeding 1 kV a.c.
Project Number 16819
Abstract/Scope This European Standard is applicable to specify the requirements for the design and erection of earthing systems of electrical installations, in systems with nominal voltage above 1 kV a.c. and nominal frequency up to and including 60 Hz, so as to provide safety and proper functioning for the use intended. For the purpose of interpreting this standard, an electrical power installation is considered to be one of the following: a) substation, including substation for railway power supply; b) electrical installations on mast, pole and tower; switchgear and/or transformers located outside a closed electrical operating area; c) one (or more) power station(s) located on a single site; the installation includes generators and transformers with all associated switchgear and all electrical auxiliary systems. Connections between generating stations located on different sites are excluded; d) the electrical system of a factory, industrial plant or other industrial, agricultural, commercial or public premises. The electrical power installation includes, among others, the following equipment: – rotating electrical machines; – switchgear; – transformers and reactors; – converters; – cables; – wiring systems; – batteries; – capacitors; – earthing systems; – buildings and fences which are part of a closed electrical operating area; – associated protection, control and auxiliary systems; – large air core reactor. NOTE In general, a standard for an item of equipment takes precedence over this standard. This European Standard does not apply to the design and erection of earthing systems of any of the following: – overhead and underground lines between separate installations; – electric railways; – mining equipment and installations; – fluorescent lamp installations; – installations on ships and off-shore installations; – electrostatic equipment (e.g. electrostatic precipitators, spray-painting units); – test sites; – medical equipment, e.g. medical X-ray equipment. This European Standard does not apply to the requirements for carrying out live working on electrical installations.


Current Stage code 6060
Current Stage code date 2010-11-05
Current Stage code deadline 2011-11-01
Deadline date for vote 2008-10-30


Order Voucher  


IEC Technical Body IEC/TC 99
Reference Document  
ICS 29.120.50 - Fuses and other overcurrent protection devices
Keywords Power installations; Earthing aspects
Note Project developed in // with maintenance of IEC 61936-1 (pr=16838) - Together with EN 61936-1:2010, supersedes HD 637 S1:1999
A-Deviation(s) CH, FR, GB, SE
Special National Condition(s) FI


Categories - Aspects
Product Life Cycle


Deadline Date
6060 2010-11-05 2011-11-01 export to doc file  EN  FR  DE
5099 2010-11-01 2011-03-01  
5061 2010-09-30 2010-11-01  
5060 2010-07-20 2010-08-20 export to doc file  EN
5020 2010-05-14 2010-07-16 export to doc file  EN  FR  DE
4099 2009-07-20 2009-10-20  
4060 2009-03-17 2009-06-17 export to doc file  EN
4020 2008-10-10 2009-03-13 export to doc file  EN
3099 2008-04-29    
2020 2007-09-11 2007-12-31  
1099 2005-04-01 2005-12-01  

Implementation Dates

date of Ratification (DOR) (1) 2010-11-01
date of Availability (DAV) (2) 2010-11-05
date of Announcement (DOA) (3) 2011-05-01
date of Publication (DOP) (4) 2011-11-01
date of Withdrawal (DOW) (5) 2013-11-01


Supersedes HD 637 S1:1999
Superseded by  
Normative reference (6)  

(1) Date of ratification (dor) date when the Technical Board notes the approval of an EN (and HD for CENELEC), from which time the standard may be said to be approved

(2) Date of availability (dav) date when the definitive text in the official language versions of an approved CEN/CENELEC publication is distributed by the Central Secretariat

(3) Date of announcement (doa) latest date by which the existence of an EN (and HD for CENELEC), a TS or a CWA has to be announced at national level

(4) Date of publication (dop) latest date by which an EN has to be implemented at national level by publication of an identical national standard or by endorsement

(5) Date of withdrawal (dow) latest date by which national standards conflicting with an EN (and HD for CENELEC) have to be withdrawn

(6) This list of normative references is purely indicative. The only official list of normative reference is the list of the published standard.