Table 11: Faults in the safety outputs (Q)
Fault
Responses
Causes
Auxiliary voltage sup‐
ply A1 / A2 for the
safety outputs is lower
than the operating
range
•
All safety outputs of the module
are switched off
•
Output voltage supply
process data
status bit = 0
•
Auxiliary voltage supply
module sta‐
tus bit = 0
•
Fault in the voltage supply
•
Line break
•
Interruption due to a fuse
Auxiliary voltage sup‐
ply A1 / A2 for
the safety outputs is
higher than the oper‐
ating range
•
Internal error
module status bit = 0
•
Auxiliary voltage supply
module sta‐
tus bit = 0
•
Fault in the voltage supply
•
Short-circuit to other volt‐
age-carrying line
Output voltage level
is Low instead of
High when the output
is “On”, overload/over‐
current
1)
2)
•
Associated output/associated
output pair is switched off
•
Depending on the load, the
affected output may pulsate tem‐
porarily until the final switch-off
•
Status Qx short-circuit to Low
process
data status bit = 0
•
Status Qx short-circuit to Low
module
status bit = 0
•
Short-circuit or resistance
drop under load
•
Short-circuit to another line
e.g., GND
Output voltage level is
High instead of Low
when the output is
“Off”
3)
•
All safety outputs of the module
are switched off
•
Output voltage supply
process data
status bit = 0
4)
•
Status Qx short-circuit to High
process data status bit = 0
•
Status Qx short-circuit to High
mod‐
ule status bit = 0
•
Short-circuit to other volt‐
age-carrying line
Test pulses are not
detected correctly
when the output is
“On”
3)
5)
•
Short-circuit to other volt‐
age-carrying line
•
Capacitive load too high
Internal error detected
•
Safety controller switches to the
critical error status
•
Internal error
module status bit = 0
•
Internal device error
•
Capacitive load too high
1)
Depending on the voltage supply used, an overcurrent can also result in the voltage supply dropping out.
2)
Reset of the error: set the process data bit of the safety output to 0.
3)
Reset of the error: the process data bits for all safety outputs of the module are simultaneously 0 and the
output level is Low.
4)
In the case of a High instead of a Low on a safety output, the supply to all safety outputs is switched off
internally. If the cause of a short-circuit is in the wiring to 24 V, then the affected signal remains High and
all other signals switch to Low.
Check if this is an undesired but valid signal value for the receiver, e.g., for the switching of the
monitoring case of a SICK safety laser scanner by means of a complementary signal.
5)
Depending on the size of the capacitive load, this may lead in certain cases to an incorrect interpretation
as an internal error since the effect on the output voltage is only temporary.
Critical error status
Consequences of the critical error status:
•
All applications are stopped.
•
All safety outputs are switched off.
•
All process data = 0
•
Evaluation of the process data status bits in the logic is no longer possible.
•
Only limited diagnostics can be performed in the critical error status.
Alternatives to resetting the critical error status:
•
Restart by switching the voltage supply off and on again
•
Software reset using the configuration software
TROUBLESHOOTING
10
8024583/2020-11-10 | SICK
O P E R A T I N G I N S T R U C T I O N S | Flexi IO XTDO1
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Subject to change without notice