Historical
NEMA ICS 2.4:2003
Nema iec devices for motor service - a guide for understanding thedifferences
Identifies features, conventions, characteristics and attributes of magnetic contactors and thermal overload relays. Control products compared or contrasted in this guide are those with equivalent electrical ratings; such ratings are expressed via nameplates, catalogues or technical literature.
NEMA: National Electrical Manufacturers Association [nema]