WAGO-I/O-SYSTEM 750
Glossary 155
753-668/000-004 4FAI 0/4-20 mA Diff PROFIsafe
Manual
Version 1.0.0, valid from HW/SW Version 01/01
D
Dangerous Failure
Termination of the capacity of a unit to complete the required function (see also
“Failure”).
DC (Diagnostic Coverage)
The diagnostic coverage is the decrease in probability of dangerous hardware
failures that result from executing automatic diagnostics tests.
Default iParameter Set
A data set persistently stored in the F I/O module with default values that
correspond to the iParameter set in the delivery condition of the F I/O module.
Default Setting
The default setting is a preset value of a parameter that is used if the user does
not make any other settings (see also “Default iParameter Set”).
Diagnostic Coverage Level
See "DC (Diagnostic Coverage)".
Discrepancy Time
The discrepancy time specifies the maximum permissible duration of an
impermissibly high difference between the input measured values of two
channels (see also “Discrepancy Time Monitoring”).
Discrepancy Time Factor
The discrepancy time factor is a predefined and unchangeable constant within
formulas for calculating discrepancy times.
Discrepancy Time Monitoring
Discrepancy time monitoring is performed by the F I/O module when using the
two-channel analysis by comparing the input measured values of two analog
inputs. When the difference of both input measured values is detected as
inadmissible depends on the set permissible tolerance window (see also
“Discrepancy Time Monitoring”).
E
Error Response Time
The error response time is the time from occurrence of an error to its response in
the process image. In the process image, the channel status bit of the input
channel in the input process image changes from status 1 to status 0 (T
SRF
) in
this case.