What does the number after the hyphen on a NEMA connector refer to?

On a NEMA connector, the number following the hyphen signifies the current rating of the connector, which indicates the maximum amount of current the connector is designed to handle safely. This current rating is crucial for ensuring that the connector is suitable for the electrical load it will be carrying in a specific application.

NEMA ratings are structured such that the designations convey both the voltage and current specifications. The numeric value after the hyphen directly provides the amperage capacity; for example, a NEMA 5-15 connector is designed to handle a maximum of 15 amps. Understanding this current rating is vital for technicians and engineers to prevent overheating and potential damage to equipment or hazards in high-load scenarios.

It's important to note that the other aspects of the connector, such as voltage rating and wire gauge, are defined by the type (letters) of the NEMA connector or external specifications, but the specific numeral directly identifies the current handling capability.