106 Commissioning
WAGO-I/O-SYSTEM 750
750-666/000-003 4FDI/2FDO 24V/10A PROFIsafe V2 iPar
Manual
Version 1.2.0, valid from HW/SW Version 01/01
Discrepancy time monitoring is terminated when a valid signal status is achieved
(0-signal or 1-signal, see Section "Valence Analysis Ix & Ix+1 Parameter"),
depending on the signal status that was present at the digital inputs prior to the
beginning of discrepancy monitoring.
You can set the discrepancy time in a value range from 10 ms to 65535 ms for
each input pair separately.
Discrepancy Time Monitoring and Discrepancy Time
If you use a two-channel or two single-channel sensors that capture the same
physical process variable, changing of the input signals of the connected digital
inputs, for example due to mechanical properties or dimensional tolerances, will
be delayed.
Discrepancy time monitoring of the two-channel analysis is used to determine
sensor errors based on the chronological progression of the signal states.
Discrepancy time monitoring is activated if the signal states deviate from the
valence rule when
•
No equivalent (same) states are detected with an equivalent valence rule
•
No antivalent (opposing) states are detected with an antivalent valence rule
Activate discrepancy time monitoring only after the set input filter time has
elapsed!
Discrepancy time monitoring is only activated if the input filter time has expired.
During error-free operation, the input signals will assume acceptable signal states
within the discrepancy time period. Discrepancy time monitoring is started and
also ends before the discrepancy time expires.
Set the value of the
discrepancy time
parameter such that both digital inputs can
complete the change of signal voltage before the discrepancy time has elapsed.
Behavior of the PROFIsafe I/O module during discrepancy time monitoring
If the process image of the PROFIsafe I/O module transfers a 1-signal and a
deviation of the input signal states from the valence rule is then detected,
discrepancy time monitoring is started. Discrepancy time monitoring is not
terminated until a 0-signal is detected.
If the process image of the PROFIsafe I/O module transfers a 0-signal due to the
input signal states and a deviation of the input signal states from the valence rule
is then detected, discrepancy time monitoring is started. Discrepancy time
monitoring is not terminated until either a 0-signal or a 1-signal is detected.
As discrepancy time monitoring progresses in the PROFIsafe I/O module, the "0"
value is output from the affected input pair to the safe PLC as a safe process
image.