What is IP Rating?
IP rating is a scale of how well a multimeter or clamp meter stands up to dust and moisture.
Most people understand that the higher the IP rating, the better the DMM can withstand a dusty, moist or even a wet environment. However, at best they may be guessing based on the number, but may not really understand how the rating works and whether the equipment will actually survive a particular working condition.
To begin with, the initials IP stand for “Ingress Protection”. What can and can’t get in.
This is followed by two more numbers. The first number is a rating of particle and dust ingress protection. The second is a rating of moisture and water ingress protection. Each number represents a specific correlation to the maximum exposure the equipment can handle.
Understanding the Rating...
An IP rating of IP68 on your multimeter, would mean dust tight (6) and continuous immersion (8). Be careful with this rating as some manufacturers have a limited immersion depth and time frame. Don’t assume with an IP68 you can throw your meter in the deep end of the pool and just leave it there.
An IP67 would be dust tight and could stand a temporary immersion in water, but get it out quick, or it will die.
An IP43 would handle particles greater than 1mm in diameter, and survive water spaying on it, but a jet of water, or a drop into a bucket of water would likely mean the end!
So when choosing a digital multimeter, take into account the environment which it will likely be exposed to, and select one with the appropriate IP rating.
Note: Other special environments (such as explosive environments) are different again, and require specialist equipment for such situations.