Siemens SIMATIC ET 200AL, System Manual

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Parameters/address space
4.3 Explanation of parameters
Digital I/O module F-DI 4+F-DQ 2x24VDC/2A, 4xM12 (6ES7146-5FF00-0BA0)
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Equipment Manual, V1.0, 05/2021, A5E51082342-AA
4.3.3 DQ parameters
Maximum test period
You can assign the time interval between bit pattern tests for F-DQ DC output faults to a
value of either 100 seconds or 1000 seconds.
Functional bit pattern tests are applied to the output switches. These tests detect faulted P- or
M- output switches and wiring faults. Short circuits to other signals or power rails can be
detected. Open circuits between the wiring terminals and the load are not detected.
If an error is detected on a channel, the test interval is shortened to 60 seconds. If an error is
no longer detected on any output channel, the configured test interval is used again.
A persistent fault is reported to the fail-safe CPU and the affected channels are passivated.
Wire break
You can enable or disable wire break testing. Wire break is only detected when the channel is
in the OFF state (process value is "0").
Activated
You can enable the corresponding channel for signal processing in the safety program.
If you disable a channel, channel diagnostics are no longer reported to the F-CPU for the
deactivated channel.
Note
Whenever you disable all output channels, you do not have to power 2L+ and 2L+
undervoltage reporting is suspended.
Channel failure acknowledge
Controls whether the channel is automatically reintegrated after a fault clears or requires an
acknowledgement (manual) in the user program. Refer to "Reactions to faults (Page 61)" for
the reintegration procedure.
Note
The configuration of the "F-Parameters": "Reintegration after channel fault" parameter can
determine your ability to modify the "Channel failure acknowledge" parameter's selection.