Enclosures of electrical equipment, per characteristics where they will be installed and their maintenance accessibility, should offer a certain degree of Protection also known as Ingress Protection (IP). Standard IEC 60034-5 defines the degrees of protection of electrical equipment by means of the characteristic letters IP, followed by two characteristic numerals. NEMA also defines IP ratings for enclosures. Read IEC Ingress Protection Ratings. Read also : NEMA Ingress Protection Ratings
The IEC and NEMA IP ratings are defined for all spectrum of equipment used in an environment where dust, particles, water etc can compromise their performance. However specifically for motors, the standards define the below listed commonly used IP ratings such that there can be no misinterpretation:
Motor
|
Degree of Protection
|
First Characteristic Numeral
|
Second Characteristic Numeral
|
|
Protected Against Accidental Contact
|
Protected Against Solid Objects
|
Protected Against Water
|
||
| Open Motors |
IP00
|
Non-Protected | Non-Protected | Non-Protected |
IP02
|
Non-Protected | Non-Protected | Protected against dripping water even when tilted 15° vertically | |
IP11
|
Protection against accidental contact with the hand | Ingress of solid objects exceeding 50mm in diameter | Protection against dripping water falling vertically | |
IP12
|
Protection against accidental contact with the hand | Ingress of solid objects exceeding 50mm in diameter | Protected against dripping water even when tilted 15° vertically | |
IP13
|
Protection against accidental contact with the hand | Ingress of solid objects exceeding 50mm in diameter | Protected against dripping water even when tilted 60° vertically | |
IP21
|
Protection against the touching with the finger | Ingress of solid objects exceeding 12mm in diameter |
Protection against dripping water falling vertically
|
|
IP22
|
Protection against the touching with the finger | Ingress of solid objects exceeding 12mm in diameter | Protected against dripping water even when tilted 15° vertically | |
IP23
|
Protection against the touching with the finger | Ingress of solid objects exceeding 12mm in diameter | Protected against dripping water even when tilted 60° vertically | |
| Closed Motors |
IP44
|
Protection against the touching with tools | Ingress of solid objects exceeding 1mm in diameter | Protection against splashing water from any direction |
IP54
|
Protection against contacts | Protection against accumulation of harmful dust | Protection against splashing water from any direction | |
IP55
|
Protection against touches | Protection against accumulation of harmful dust | Protection against any water jets from any direction | |
For special and more dangerous areas where electric motors are required to be applied, the following degrees of protection are commonly used:
IPW 55 (Weather protection)
IP56 (Protections against water jets)
IP65 (Totally protected against dust)
IP66 (Totally protected against dust and water jets).