MV design guide - Schneider Electric

Design rules
Protection Index
IK code
Introduction
c Certain countries felt the need also to code the protection provided by
enclosures against mechanical impact.
To do this they added a third characteristic figure to the IP code (the case
in Belgium, Spain, France and Portugal). But since the adoption of
IEC 60 529 as the European standard, no European country can have
a different IP code.
c Since the IEC has up to now refused to add this third figure to the
IP code, the only solution to maintain a classification in this field was to
create a different code. This is a subject of a draft European standard
EN 50102: code IK.
c Since the third figure in various countries could have different
meanings and we had to introduce additional levels to cover the main
requirements of product standards, the IK indices have a different
meaning to those of the previous third figures (cf. table below).
Previous 3 rd figures of the
IK code
IP code in NF C 20-010 (1986)
IP XX1 IK 02
IP XX3 IK 04
IP XX5 IK 07
IP XX7 IK 08
IP XX9 IK 10
NB: to limit confusion, each new index is given by a two figure number.
Definitions
c The protection indices correspond to impact energy levels expressed
in joules
v hammer blow applied directly to the equipment
v impact transmitted by the supports, expressed in terms of vibrations
therefore in terms of frequency and acceleration
c The protection indices against mechanical impact can be checked by
different types of hammer: pendulum hammer, spring-loaded hammer or
vertical free-fall hammer (diagram below).
striker
latching mechanism
relief cone
pedulum pivot
arming button
support
fall height
attaching
support
specimen
Schneider Electric
Merlin Gerin MV design guide
43