Allen-Bradley GuardPLC 1753, Справочник по безопасности

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32 Publication 1753-RM002C-EN-P - September 2008
Chapter 3 GuardPLC Controller and GuardPLC I/O Module Input Channels
Emergency Off Switches
The digital outputs DO1 and DO2 are pulsed (T1 and T2 below). As a
result, the connections to the digital inputs are monitored. The signals
for the pulsed outputs must begin at DO1(01) and must be directly
sequential.
Digital Input Monitoring
The FAULT LED indicator on the front plate of the controller/module
flashes, the inputs are set to 0 and an error code is generated when
these faults occur.
•
Short-circuit between two parallel connections
•
Reversal of two connections
•
Ground fault on one of the lines
•
Line break (or opening of the contacts when one of the
Emergency OFF switches is pressed)
DO 1 2
DI 1 2 DI 3 4
Emergency
OFF 2 Emergency
OFF 1
T1
T2
time
configurable 5…2000
μ
s
configurable 5…2000
μ
s