Specifications

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As the S7-1200 PLC executes its control program, it receives
inputs from manual switches mounted on the front of the
panel. It also communicates with a SIMATIC HMI operator panel
that provides for manual inputs from the machine operator
or maintenance person and displays alphanumeric messages
indicating machine status. The PLC also receives inputs from
other control devices such as limit switches or proximity
switches that change state as a result of machine operations.
In this example, the PLC controls relays, contactors, and other
devices that turn on and off to control various aspects of the
machine.
Simatic HMI
Operator Panel
S7-1200 PLC
SITOP Power Supply
Molded Case
Circuit Breaker
SIMATIC
S7-1200
Computer Numerical PLCs are not the only control systems used for machines.
Controls (CNC) Consider, for example, the type of control system required
by machine tools, such as lathes, grinding machines, punch
presses, and machining centers. Machine tool control systems
typically incorporate a PLC, a computer numerical control
(CNC), and related components such as servo drives and servo
motors. CNC machine tools are used to cut or machine to
complex and exacting specifications.
Siemens offers a range of SINUMERIK CNC models, which
includes models for basic machines, dynamic machining, high-
speed machining, and PC-based CNC. In addition, Siemens
offers compatible servo drives and servo motors as well as
other motion control components and systems. These products
provide the coordinated multi-axis control needed for milling,
drilling, turning, grinding applications, and other applications.