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Understanding IP Protection for IEC metric motors.

Protection Against Solids   Protection Against Liquids
IP Proof Description   IP Proof Description
0   No Protection against solids.   0   No Protection against liquids.
1 Protection from solid foreign bodies of diameters greater than 50mm (2").

i.e. Accidental contact by the hand.


  1 Protection from vertical drops of liquid. (condensation).
2 Protection from solid foreign bodies of diameters greater than 12mm (7/16")

i.e. Accidental contact by fingers.

  2 Protection from vertical drops of liquid from 15 degrees off of top center. 
3 Protection from solid foreign bodies of diameters greater than 2.5mm (1/10")

i.e. wire, tools.

  3 Protection from liquid sprinkled from 60 degrees of top center.
4 Protection from solid foreign bodies of diameters greater than 1mm. (1/25")

i.e. fine wire, small tools

  4 Protection against jets of water from any direction.
5 Protection from the ingress of dust.  No harmful deposits.   5 Protection against water projected by a nozzle from any direction.
6 Complete protection from the ingress of dust.   6 Protection against water projection similar to sea waves.
        7 Protection against the effects of immersion.

IP CODE or IP System for Ingress Protection Rating

Ingress Protection Rating, or occasionally referred to as International Protection Rating, is a system of two digits followed by the letters IP and is standardized on the nameplates of IEC metric frame motors and occasionally NEMA frame motors seeking a standard international rating classification. 

This standard provides more informative description of protection from dust or liquids than various obtuse marketing terms such as dust proof, water resistant, air-tight, and so on.

The IP rating system is also used on a wide variety of electrical and mechanical devises such as electrical plugs, and other components.  The IP system is not expressed as a guarantee for use but a reference for design & application.

IP55, IP56, IP65, IP66, IP67, IP54 are common protection levels for IEC metric motors in Europe and America.  The table above is designed to help you understand the meaning of the codes.  The first number signifies protection against solids, the second number for liquids.

IEC refers to the International Electrotechnical Commission.  For more detailed information regarding IEC standards and definitions, please visit their website via this link.

Users familiar with the NEMA system of Enclosure Standards for motors can be confused with the more precise IP system for I.E.C. type motors. 

  • Drip-Proof is protection from liquid falling into motors within upto 15 degrees from vertical (such as in IP..2). 

  • Totally Enclosed Air Over (TEAO) is a motor that is "dust tight" for fan or blowers where the fan is mounted to the motor shaft or belt driven within the airflow of the fan.

  • Totally Enclosed Non-Ventilated (TENV) motors have NO ventilation openings, are enclosed to prevent free exchange of air (not air-tight) and have no external cooling fan; convection cooling.

  • Totally Enclosed Fan Enclosed (TEFC) Motors are similar to TENV however incorporate an external cooling fan on the motors shaft.  Air is drawn over the motor for cooling.

  • Totally Enclosed Hostile and Severe Environment are motors designed to be used in Hostile and Severe conditions, where moisture or chemical environments are expected, but NOT for hazardous or explosive locations.

  • Totally Enclosed Blower Cooled - These motors are similar to a TEFC, but a cooling fan powered by a separate motors is used for full cooling regardless of motor speeds.  Ideal for Inverter Use.  In IEC/mm applications, this is often referred to as SERVO VENT.

  • Explosion Proof Motors - These motors are designed for use in applications where explosive gases, vapors, or combustible dusts are found.  The groups are broken down specifically into various gasses and dusts by NEMA.  (National Electrical Manufacturers Association).  For IEC type motors, we refer to ATEX standards for comparable classifications. "Design-Marketing-SEO"