Siemens SIMATIC OEM PP32, Руководство по эксплуатации оборудования

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1-7
OEM Push Button Panel Equipment Manual
Release 08/98
Two LEDs are integrated in the keys and are used to display the bit status of
the connected PLC. The LEDs can indicate four different statuses, one of
which can be defined via parameters.
All the operating elements of the Push Button Panels are linked to bits in the
PLC. The keys on the Push Button Panel can be used to influence the bits in
the PLC and thus control the affect of processes. At the same time, the LEDs
indicate the bit status of the PLC and, thus, the operating status of the process
being monitored.
When several keys are pressed simultaneously, it is detected by the Push
Button Panel and the bits are set in the PLC. After restarting the system
following a power failure, all the bits are set to 0.
Additional 22.5 mm elements can be connected using the digital inputs and
outputs. Non-connected digital inputs are automatically set to 0.
The release input serves to lock the Push Button Panel. A key-operated switch
can be connected here, for example. The release input permits switching
between normal operation (open contact) and monitoring mode (closed
contact). In normal operation, all the functions on the Push Button Panel are
available for use, whereas in monitoring mode, the following restrictions are
valid
S
the inputs are locked, no signal exchanges are reported to the PLC,
S
the last status of all the keys is maintained by the PLC until normal
operation returns.
Operating concept
Digital inputs and
outputs
Release input
Product Description