Gibbons jargon buster #4: What are IP ratings?

We reveal what IP ratings mean and why they're a vital consideration when ordering an electric motor. 

In our recent blog explaining the information found on an electric motor nameplate, we briefly covered IP ratings. But what are IP ratings?

Standing for Ingress Protection, the IP rating classifies the motor enclosure’s protection from objects, dust and moisture. The standard is published by the International Electrotechnical Commission (IEC).

IP ratings are made up of two digits which represent protection against ingress of solid objects and liquids respectively. An ‘x’ is used in place of a digit if there is only one class of protection.

First digit

This refers to the degree of protection (of people) against access to hazardous parts, plus protection of the motor from intrusion by solid bodies.

0 - No special protection.

1 - Protection from a large body part such as a hand (but no protection from deliberate access) and from solid objects greater than 50mm in diameter.

2 - Protection against fingers or objects not greater than 80mm in length and 12mm in diameter.

3 - Protection from entry by tools and wires with a diameter greater than 2.5mm.

4 - Protection from entry by solid objects with a diameter greater than 1mm.

5 - Dust protected, meaning dust may enter but not in a quantity that would harm operation.

6 - Dust tight – hermetically sealed and completely protected against contact.

Second digit

This states the motor’s degree of protection against moisture ingress.

0 - No special protection.

1 - Protection from vertically dripping water.

2 - Protection from vertically dripping water when the enclosure is tilted at an angle of up to 15° from its normal position.

3 - Protection from spraying water falling from an angle of up to 60°.

4 - Protection against splashing water from all directions, equivalent to garden sprinkler or handheld shower head projecting 12.5 litres per minute.

5 - Protection from low-pressure water (equivalent to a 6.3mm nozzle at 12.5 litres per minute).

6 - Protection against powerful jets of water (equivalent to a 12.5mm nozzle at 100 litres per minute) such as on a ship’s deck.

7 - Protection against immersion in up to 1m of water for no more than 30 minutes.

8 - Protection against complete, continuous submersion in water beyond 1m, meaning the motor must be hermetically sealed or allow water to enter only at a level where it causes no harm.

So, for instance, an electric motor rated IP55 will be dust protected and able to withstand low-pressure water exposure, making it suitable for most industrial applications.

You should always look for a motor’s IP rating before making a purchase and consider the environment it will be used in to ensure adequate protection. If you’re in any doubt, don’t hesitate to contact our team of expert engineers who are here to answer any technical queries you may have. Give us a call on 01621 868138 or email info@gibbonsgroup.co.uk and we’ll be happy to help.