IP rating
The ingress protection rating, or IP rating, of electrical equipment such as transformers and chokes, is defined according to DIN EN 60529 (VDE 0470-1).
These ratings, supplemented by two numbers following the letters “IP”, provide information on protection against contact and foreign bodies (first number) as well as protection against water (second number). See EN / IEC 60529 for further information.
Common protection classes of enclosures are IP20, IP23, IP44, IP54 and IP65.
Number
|
Protection against solid foreign objects… |
Protection
against water… |
0
|
not protected | not protected |
1
|
… greater than 50mm / …hand | drop vertical |
2
|
… greater than 12.5mm / …finger | drops inclined up to 15 |
3
|
… greater than 2.5mm / …tools | spraying water up to 60° |
4
|
… greater than 1mm / … wires | splashing water any direction |
5
|
dust protected | jet with nozzle |
6
|
dust-tight | strong jet with nozzle |
7
|
— | temporary immersion |
8
|
— | permanent immersion |
Note:
Some transformer manufacturers label transformers with IP20 even if they have no housing and no cover. They argue that – provided the terminals are protected against accidental contact – the windings are protected by insulating tape or plastic covers. BREMER-Transformatoren cannot endorse this view. We designate a transformer without a cover as IP00. For protection class IP20, we either use ready-purchased sheet steel or plastic enclosures or we manufacture at least one cover made of aluminium or perforated sheet steel or plastic.