IEC 61936-1 Ed. 2.1 b:2014

Power installations exceeding 1 kV a.c. - Part 1: Common rules

IEC 61936-1:2010+A1:2014 provides common rules for the design and the erection of electrical power installations in systems with nominal voltages 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 standard does not apply to the design and erection 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 standard does not apply to the design of factory-built,  type-tested switchgear for which separate IEC standards exist. This standard does not apply to the requirements for carrying out live  working on electrical installations. This second edition cancels and replaces the first edition, published in 2002. It constitutes a  technical revision. The main changes with respect to the previous  edition are listed below:
 - new table of references for additional agreements between  manufacturer/contractor/planer and user/orderer/owner (4.1.2);
 - addition of minimum clearances in air not standardized by IEC but  based on current practice in some countries (Annex A);
 - deletion of nominal voltages (Table 1, Table 2, Clause 5);
 - addition of regulations for fuses (6.2.15);
 - simplification of regulations for escape routes (7.5.4);
 - deletion of special regulations for operating aisles (7.5.4);
 - modification of clearances for fire protection (Table 3);
 - modification of safety criteria for earthing systems (10.2.1);
 - modified curves of permissibly touch voltages (Figure 12, Annex B);
 - deletion of numbering of subclauses without headlines;
 - change of "should" to "shall" in many cases or change of  subclauses with "should" to a note.   This consolidated version consists of the second edition (2010)  and its amendment 1 (2014). Therefore, no need to order amendment in addition to this publication.