Technical Articles

NEMA Nomenclature

The NEMA (National Electrical Manufacturers Association) pattern and numbering system is made up of four main identifiers. The first identifier can be a blank space or have the letter L. This determines whether it is a straight or locking blade device. The second identifier is a number. The first number in a NEMA listing determines the voltage rating. The third identifier is a number and identifies the amperage rating of the device. The fourth identifier is a letter. This identifier determines whether the device is a plug, P, or a receptacle/outlet, R.The North American Non-locking NEMA Configuration chart will help you determine the correct NEMA configuration for your North American applications.