Specifications

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Assembly Processes
Assembly processes may involve assembling an entire system
or subsystem at one location. In many cases, however, parts
are mounted sequentially through a series of assembly stations.
Units being assembled are moved from station to station via
some type of transporter mechanism, such as a conveyor. Any
specific assembly station may utilize only manual assembly
operations or may include one or more machine operations.
The latter is particularly true when just-in-time manufacturing
techniques, requiring parts to be manufactured as needed, are
employed.
Motors There are many aspects of assembly processes that are similar
to discrete parts manufacturing and, in fact, many factories
combine both types of processes. Therefore, it should come
as no surprise that the electrical products used in both types
of processes are often the same. For instance, AC motors are
used in both types of processes to change electrical energy into
mechanical energy, the reverse of what a generator does.
In the United States, the most common type of industrial
motor is a NEMA frame size, three-phase AC induction
motor. The term “NEMA frame size” indicates that a motor has
frame dimensions that correspond to a National Electrical
Manufacturers Association specification. Siemens NEMA
motor product line includes general purpose motors with light-
weight die cast aluminum or rugged cast iron frames as well as
severe duty, hazardous duty, inverter duty, and vertical motors.
Siemens also manufactures a variety of motors too large to
correspond to NEMA frame dimensions (above NEMA motors)
and motors that comply with International Electrotechnical
Commission (IEC) specifications.