Siemens SIMATIC ET 200AL, System Manual

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Interrupts/diagnostic messages/diagnostics
6.1 Reactions to faults
Digital I/O module F-DI 4+F-DQ 2x24VDC/2A, 4xM12 (6ES7146-5FF00-0BA0)
Equipment Manual, V1.0, 05/2021, A5E51082342-AA
63
communication errors or supply voltage errors are always manually reintegrated. Fatal
diagnostic errors require a power cycle with successful diagnostics to reintegrate.
Automatic
Channels that you select to be automatically reintegrated are immediately reintegrated when
the fault has cleared.
Manual
Channels that you select to be manually reintegrated are acknowledged in your program
after the fault has cleared.
The "ACK_REQ" bit for that module goes true to indicate that reintegration is possible. After
the "ACK_REQ" bit is true, your program can set the "ACK_REI" bit to allow the reintegration of
all channels in that module that are ready to be reintegrated.
You can also acknowledge all faults in an F-runtime group using the "ACK_REI_GLOB" input of
the "ACK_GL" instruction.
Reintegration after high stress events
High temperature, high voltage, or excessive current stress can damage electronics, reducing
the reliability while components continue to work apparently as expected. Passivation does
not remove the potentially damaging effects of high ambient temperature or high applied
voltage. Solid state switch outputs can be damaged by high currents prior to protective
device activations. The PFD and PFH reliability calculations assume the fail-safe module is
operated within its specified operating parameters. When a module has passivated due to a
high stress event, even though it apparently works correctly and passes all diagnostics, the
probability of a future dangerous failure may be increased.
WARNING
It is possible to reintegrate a channel or module while some fault is still present that is
not readily detected by the module diagnostics.
Reintegration of a faulty system can result in unexpected machine or process operation,
which may cause death or serious injury to personnel, and/or damage to equipment.
After any reported fault, the steps outlined in this chapter and in safety standards applicable
to your system should be followed to assure that the fault is completely understood and
corrected before reintegration.
For an exact list of faults for the module, refer to "Fault types, causes, and corrective
measures (Page 70)".
At reintegration, the following occurs:
•
For a fail-safe module digital input, the process values pending at the fail-safe inputs are
again provided for the safety program.
• For a fail-safe module digital output, the output values provided in the safety program are
again transferred to the fail-safe outputs.