How Do International Protection (IP) Ratings Differ from NEMA Ratings for Heating Plate Sealing?

There are two main systems (IP codes and NEMA ratings) used all over the world to represent how much protection is offered by electrical enclosures. When specifying heating plates for use in worldwide installations it is important to understand the similarities and differences between different systems.

Introduction to IP and NEMA Ratings 
IP (Ingress Protection) Ratings 
The Ingress Protection (IP) rating system, specified by IEC 60529, is a widely used system worldwide. It shows the level of protection that the enclosure provides for solids and liquids in two digits:

The first number (0 to 6) indicates protection against solid items like dust or debris.

Second digit (0-9): Protection against liquids, especially water (light splashes to forceful water jets).

For example, IP65 stands for:

6: Protection against dust.

5: Protection against water jets from all directions (low pressure).

NEMA Ratings:
NEMA has its own rating system, defined in NEMA 250. NEMA ratings define the degree of protection provided by enclosures under various environmental circumstances by means of a type number. These ratings include considerations for dust, water, corrosion, ice, oil and hazardous environments.

Common NEMA ratings include :

NEMA 4: Protection against dust, splashing water and hose directed water.

NEMA 12: Protects against dust, dirt and falling debris.

NEMA 4X: Contains all the protections of NEMA 4 plus extra corrosion resistance, generally by means of stainless steel construction.

IP vs. NEMA Rating of Heating Plates
Comparable Ratings
Both methods address the level of environmental protection of electrical enclosures, however they have different techniques and scopes:

Water protection – IP65 is basically comparable to NEMA 4. Both ratings are for protection against dust and low-pressure water jets.

The second digit of 6 in IP66 means better water protection equal to NEMA 4X and corrosion resistance.

NEMA 4X provides the same protection against water and dust as IP66 , but also guarantees that the enclosure is corrosion resistant ( something IP codes do not cover ) .

The big difference is that NEMA ratings like NEMA 7 and NEMA 9 are for hazardous settings, meaning they are made for use among explosive gases or dust. IP ratings do not include hazardous site or corrosion resistance.

What rating should you rate?
IP ratings are the standard for Europe and much of the world, therefore they're critical for worldwide installations and compliance with international standards.

NEMA ratings are most typically seen in North America, and are generally required for installations in the U.S. and Canada.

For global manufacturers who transport items around the world, heating plate IP vs NEMA rating often appear on the same nameplate. This allows to accurately specify the product depending on the region of installation.

NEMA Ratings Conversion IP
NEMA Rating Approximate IP Rating Equivalent Description
NEMA 1 IP10 General purpose indoor, not protected from water
NEMA 4 IP65 Dust and water jet resistant
NEMA 4X IP66Protection against water jets and corrosion
NEMA 12 IP52 Protection against dust and water splashing
NEMA 7 Not directly equivalent Explosion-proof for dangerous locations
NEMA 9 No direct equivalent Explosive dust atmosphere
Summary
Both the IP and NEMA ratings indicate enclosure protection, however they are not interchangeable, as they come from distinct standards. NEMA ratings are for general protection against environmental conditions, including corrosion and hazardous situations, whereas IP ratings are specifically for ingress protection. Knowledge of both rating systems helps in the proper specification of heating plates for varied installation settings around the world.

In a hostile industrial environment, the protection of the enclosure is a key element in the reliability of heating plates. Choosing the right IP vs NEMA rating of the heating plate will ensure the safe and effective operation of the equipment in food processing, pharmaceutical production or hazardous situations.