IP codes

[bencrockett15]

Hey guys , i got my 2391 inspection and testing exam coming up and Ip codes are coming up alot in the past papers, is there an easy way of remembering them ? cheers.

 

[Richard Burns]

Mainly just have to remember them, the key ones that come up are 2 and 4 for solids and 4 and 5 for liquids. The B and D just have extras on them from 2 and 4.
IPXX
My mental methods may well be off the wall and so not meet your needs but:
Liquids are Last
so the last number is liquid protection, first number is solid protection
On solids
Relating from four to one: IP4X is 1mm IP3X is 2.5mm "add" 3 and 4 to get IP2X at 12.5mm and multiply by four to get IP1X at 50mm.
(can also think light and power cable sizes for 4 and 3)

On liquids for the first 3 I imagine a circle filling in:
IPX1 is a straight line (vertical drops) this curves round to make IPX2 at 15 degrees and add another curve to get IPX3 at 60 degrees.
IPX4 to IPX8 are all round (circle filled in), moving from splashing, to jets to strong jets to covered in water to always in water. I think of pushing something into water with more and more power until it is permanently under water.

 

[SirKit Breaker]

You wont be asked to quote an IP code such as IP65, but you will need to remember that
IP2X=IPXXB
IP4X=IPXXD

2 is the second letter of the alphabet B
4 is the fourth letter of the alphabet D

These are the main ones that crop up, and i dont want to fog the issue for you. Richards post above sums it up.

Cheers..........Howard