User manual

68 Publication 1756-RM093F-EN-P - January 2010
Chapter 7 Monitor Status and Handle Faults
The CONNECTION_STATUS data type contains RunMode and
ConnectionFaulted status bits. The following table describes the
combinations of the RunMode and ConnectionFaulted states.
Input and Output Line Conditioning
I/O modules provide pulse test and monitoring capabilities. If the
module detects a failure, it sets the offending input or output to its
safety state and reports the failure to the controller. The failure
indication is made via input or output status and is maintained for a
configurable amount of time after the failure is repaired.
I/O Module Connection Status
The safety protocol portion of the controller’s operating system
provides status for each I/O module in the safety system. If an input
connection failure is detected, the operating system sets all associated
Safety Connection Status
RunMode
Status
ConnectionFaulted
Status
Safety Connection Operation
1 = Run 0 = Valid Data is actively being controlled by the producing
device. The producing device is in Run mode.
0 = Idle 0 = Valid The connection is active and the producing device is
in the Idle state. The safety data is reset to zero.
0 = Idle 1 = Faulted The safety connection is faulted. The state of the
producing device is unknown. The safety data is
reset to zero.
1 1 Invalid state.
ATTENTION
Safety I/O connections and produced/consumed connections
cannot be configured to fault the controller if a connection is
lost and the system transitions to the safe state. Therefore, if
you need to detect a module fault to ensure that the system
maintains SIL 3, you must monitor the Safety I/O
CONNECTION_STATUS bits and initiate the fault via program
logic.
IMPORTANT
You are responsible for providing application logic to latch
these I/O failures and to make sure the system restarts
properly.