The letters ‘IP’ are followed by two numbers which indicate the degree of protection offered.
The first number after 'IP' refers to protection from solid objects:
1 = Protection from objects greater than 50mm diameter
2 = Protection from objects greater than 12.5mm diameter, such as a finger
3 = Protection from objects greater than 2.5mm
4 = Protection from objects greater than 1.0mm, such as wire, large chips and shavings, etc.
5 = Ingress of dust is not totally prevented, but it doesn’t enter in harmful quantities that would interfere with safe and accurate operation
6 = No ingress of dust permitted
The second number after 'IP' refers to protection from liquids:
0 = No protection
1 = Protection from falling drops of water
2 = Protection from drops of water falling at an angle of 15° in 4 fixed positions
3 = Protection from low pressure spray at an angle of up to 60° from vertical
4 = Protection from low pressure spray at an angle of up to 180° for 10 minutes
5 = Protection from medium pressure jet – 6.3mm diameter, from any angle for 3 minutes at a distance of 2.5-3 meters
6 = Protection from high pressure jet – 12.5mm diameter, from any angle for 3 minutes at a distance of 2.5-3 meters
7 = Protection from temporary immersion in water under set conditions – 1 meter for 30 minutes
8 = Protection from the effects of continuous immersion in water, ingress of water in quantities causing harmful effects shall not be possible
9 = Protection from steam cleaning, high pressure, or high temperature jet wash
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