Safety Manager Safety Manual - Tuv-fs.com

SM IO faults
SM IO faults
Tip:
For more information on repair timer settings or fault reaction states as referred to in these
topics, see “Introduction” on page 19.
These topics provide an overview of detected IO faults and the Controller
response to these faults.
Digital input faults
Table 9 on page 27 provides an overview of faults that can be detected in relation
to digital inputs and the response to these faults.
Table 9 Controller response to digital input faults
Digital input faults
Related to
digital input loop **
(line monitored)
Diagnostic message
reports
Non redundant input
Controller response *
lead breakage apply FR state apply FR state
short circuit
Redundant input, Controller response
CP X (faulty input) CP Y (healthy input)
loop power**
power output to sensors
shorted
apply FR state
use values from
CP Y
***
none -continue
channel module faulty apply FR state use values from
CP Y ***
module module faulty apply FR state use values from
CP Y ***
compare **** input compare error apply FR state apply FR state
none -continue
none -continue
* If the Controller is redundant, both CPs respond the same.
** This fault is usually caused by an anomaly in the field, not by a defect of an input module.
*** If values are not available via CP Y apply FR state to affected inputs.
**** Occurs when detecting a difference in the input values persists for more than 2 application cycli.
Safety Manager Safety Manual 27