Specifications

93
Motor Insulation Class Standards established by the National Electrical Manufacturers
Association (NEMA) to meet motor temperature requirements
found in different operating environments. The combination of
an ambient temperature of 40°C and allowed temperature rise
equals the maximum winding temperature of a motor. A margin
is also allowed to provide for a point at the center of the motor’s
windings where the temperature is higher.
Motor Starter Often refers to a contactor and an overload relay assembled
together to remotely control the operation of a motor while
providing overload protection. This definition applies to a full
voltage starter. A variety of other starter types are also available.
Mutual Induction A process that occurs when varying lines of magnetic flux from
one conductor induce a voltage in an adjacent conductor. This is
the basic operating principle of a transformer.
National Electrical
An organization of manufacturers of electrical equipment that,
Manufacturers Association among other things, develops standards for electrical
(NEMA) equipment.
National Electrical Code® A document revised every three years based upon inputs to
(NEC ®) and recommendations of volunteer committee members of
the National Fire Protection Association. The intent of the NEC
®, also called NFPA 70®, is to describe safe electrical practices.
Although the NEC® is an advisory document, its use is often
mandated by state and local building codes.
National Fire Protection
A private, nonprofit organization with international
membership.
Association (NFPA) The NFPA has been the sponsor of the National Electrical Code®
(NEC
®) since 1911.
NEMA Enclosure Type A designation given to an enclosure based on standards
published by the National Electrical Manufacturers Association.
The NEMA type identifies the degree of protection provided by
the enclosure.