8.4 Lockout Conditions
Input lockout conditions are generally resolved by repairing the fault and cycling the input Off and then back On.
Output lockout conditions (including EDM and AVM faults) are resolved by repairing the fault and then cycling the Reset
Input connected to the FR node on the Safety Output.
System faults, such as low supply voltage, overtemperature, or voltage detected on unassigned inputs, may be cleared by
cycling the System Reset input (any Reset Input assigned to be the System Reset). Only one reset button can be
configured to perform this operation.
A system reset is used to clear lockout conditions not related to safety inputs or outputs. A lockout condition is a response
where the Controller turns Off all affected Safety Outputs when a safety-critical fault is detected. Recovery from this
condition requires all faults to be remedied and a system reset to be performed. A lockout will recur after a system reset
unless the fault that caused the lockout has been corrected.
A system reset is necessary under the following conditions:
•
Recovering from a system lockout condition
•
Starting the Controller after a new configuration has been downloaded
For internal faults, the System Reset likely will not work. The power will have to be cycled in an attempt to run again.
WARNING: Non-Monitored Resets
If a non-monitored reset (either latch or system reset) is configured and if all other conditions
for a reset are in place, a short from the Reset terminal to +24 V will turn On the safety
output(s) immediately.
WARNING: Check Before Reset
When performing the system reset operation, it is the user’s responsibility to make sure that all
potential hazards are clear and free of people and unwanted materials (such as tools) that could be
exposed to the hazard. Failure to do so may result in serious bodily injury or death.
XS/SC26-2 Safety Controller
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