Medium Voltage Application Guide

SWITCHGEAR
4.10 Protection index
IP Ratings
IEC 60529 specifies levels of protection against the ingress of different items. Ingress protection (IP) codes are
composed of up to four elements:
Characteristic 1: Solid foreign objects
Characteristic 2: Harmful ingress of liquid
Additional letter (optional): Object used for access
Supplementary letter (optional): Application specific
IP rating components
Characteristic 1 Characteristic 2 Additional Letter Supplementary Letter
0 Non-protected Non-protected A = back of hand H = high voltage apparatus
1 ≥ 50 mm diameter Vertically dripping B = finger M = motion during water test
2 ≥ 12.5 mm diameter Dripping at 15 ° tilt C = tool S = stationary during water test
3 ≥ 2.5 mm diameter Spraying D = wire W = weather conditions
4 ≥ 1.0 mm diameter Splashing
5 Dust-protected Jetting
6 Dust-tight Powerful jet
7 Temporary immersion
8 Continuous immersion
Source: IEC 60529
IEC 62271-1 specifies protection ratings for enclosures. Equipment designed for indoor installation is not typically
IP rated against ingress of water (a placeholder X is used instead of a rating for this characteristic):
IP ratings for equipment installed indoors
Degree of Protection against ingress of solid foreign Protection against access to hazardous parts
Protection
objects
IP1XB Protected against solid objects greater than 50
mm
Access with a finger (test-finger 12 mm
diameter, 80 mm length)
IP2X Protected against solid objects greater than 12.5
mm
Access with a finger (test-finger 12 mm
diameter, 80 mm length)
IP2XC Protected against solid objects greater than 12.5
mm
Access with a tool (test rod 2.5 mm diameter,
100 mm length)
IP2XD Protected against solid objects greater than 12.5
mm
Access with a wire (test wire 1.0 mm diameter,
100 mm length)
IP3XC Protected against solid objects greater than 2.5
mm
Access with a tool (test rod 2.5 mm diameter,
100 mm length)
IP3XD Protected against solid objects greater than 2.5
mm
Access with a wire (test wire 1.0 mm diameter,
100 mm length)
IP4X Protected against solid objects greater than 1
mm
Access with a wire (test wire 1.0 mm diameter,
100 mm length)
IP5X Protection against harmful entry of dust Access with a wire (test wire 1.0 mm diameter,
100 mm length)
Source: IEC 62271-1
Page 170 Medium Voltage Application Guide 710-12280-00A