Siemens Simatic S7-300, Инструкция по установке и эксплуатации

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Glossary
Fail-safe signal modules
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Installation and Operating Manual, 01/2010, A5E00085586-10
Channel number
Channel numbers are used to identify the I/O of a module and to assign channel-specific
diagnostic messages.
Channel-selective passivation
When a → channel fault occurs, only the relevant channel is passivated in this passivation
method. The channels of the affected channel group/all channels of the fail-safe signal
module are passivated when a channel group fault/module fault is detected.
CiR
CiR = Configuration in RUN. System modification in RUN by means of CiR allows the
configuration of units of an active system with distributed I/O. Process execution is
interrupted for the duration of a brief, assignable period. The process inputs retain their last
value during this period.
CiR is only possible in deactivated safety mode.
Configuring
Systematic arrangement of the signal modules (configuration
CRC
Cyclic Redundancy Check → CRC signature check
CRC Signature
The process data in the safety message frame, the address correlations and the safety-
relevant parameters are validated by means of a CRC signature in the safety message
frame.
Dark period
Dark periods are generated in the course of shutdown tests and complete bit pattern tests.
The fail-safe output module transfers test-specific zero signals to the active output. The
output is then switched off briefly ("dark period"). A sufficiently slow → actuator does not
respond to this signal and remains active.