When you specify electrical enclosures from a global manufacturer, you may notice along with a NEMA rating there is also an IP or Ingress Protection rating. An electrical enclosure IP rating a European standard that gives buyers an idea of how much protection is offered against environmental conditions that feature liquid or particles. The IP rating system was established by the International Electromechanical Commission (IEC), a worldwide organization for standardization.
Basics of Electrical Enclosure IP Ratings
All electrical devices have an IP rating that is defined in international standard EN 60529. The benefit is that no matter where you purchase your electrical enclosures or other electrical devices, this rating system will let you know just how weatherproof or waterproof the component is. The IP rating means the electrical box has been tested against infiltration of water, dirt, and other foreign bodies.
The degree of protection is then categorized by a two-digit IP number that refers to the level of protection. The first digit (from 0-6) is the amount of protection against solids, while the second digit (from 0-8) is the protection rating against liquids.
For each digit, the level of protection increases from low to high as the digits increase low to high. An IP rated enclosure with a second digit as “zero” means the electrical panel or electrical box has no special protection against liquids.
NEMA Ratings vs. IP Ratings
So, just how does an IP rating compare to a NEMA rated electrical enclosure? NEMA ratings are assigned by where the electrical cabinet will be sitting or the ambient environment. For example, electrical cabinets installed outdoors, or in a corrosive environment, or in a retail store’s electrical room may have ratings of NEMA 3R, NEMA 12, and NEMA 1 respectively.
IP ratings judge electrical enclosures on how well the cabinet is built. It doesn’t matter where the electrical enclosure sits, only what size particles or liquid infiltration is in that environment. This is where the term Ingress Protection is derived from.
The main consideration when comparing NEMA ratings and IP ratings is that a NEMA rating gives more information about the electrical enclosure. This includes whether the cabinet is corrosion resistant from atmospheric gasses or liquids and if the enclosure can be used in a hazardous environment.
Converting Between NEMA and IP Ratings
Because each system is measuring a different set of electrical enclosure characteristics, there is no direct conversion between NEMA and IP ratings. It is best to use both if possible. The IP rating may give you a clearer picture of how “water-resistant” or “dust-proof” the electrical box is, while the NEMA rating tells you how the box will function overall as tested in that same environment.
While the two rating systems are not directly equivalent, you will still find comparison or equivalence charts online that can give you substitution information. The equivalent NEMA rating will typically meet or exceed the IP rating of the electrical enclosure.
Visit Allied Moulded Products for a wide range of fiberglass electrical enclosures and polycarbonate electrical boxes that have been tested and rated for compliance to both NEMA and IP standards.