10.1.5.2
Safety-related parameters
The following parameters are the safety-related parameters of the device:
Parameter ID Parameter name on
the display
Meaning
S1
PV SELECT
Pressure is the primary variable. The parameter cannot be
changed.
S2
DAMPING
Damping value [04] (Page 105)
S3
UPPER RANGE
Set upper range value parameter [03] (Page 104)
S4
LOWER RANGE
Set lower range value parameter [02] (Page 104)
S5
APPLICATION
To set these parameters, change the device mode to "Functional Safety disabled".
10.1.5.3
Device mode "Functional Safety enabled"
In "Functional Safety enabled" device mode, an internal diagnostics process of the device
performs the following safety-related checks:
● Sensor breakage monitoring
● Continuous testing of execution and logic behavior of CPU, analog-to-digital converter and
memory
● Temperature monitoring
● Pressure monitoring
● Integrity of safety-related parameters
● Plausibility check of current output
When a safety-related critical error is detected in the device, the current output signal
corresponds to the fault current (≤ 3.55 mA) and is independent of the settings of the following
parameters:
Select fault current [10] (Page 120),
Lower fault current [11] (Page 120),
Upper fault current [12] (Page 121),
Lower saturation limit [13] (Page 121),
Upper saturation limit [14] (Page 122)
Note
As long as the device is in the "Functional Safety enabled" device mode, all parameters are
protected against changes.
● To change the parameters, disable Functional Security.
Functional Safety
10.1 Safety concept
SITRANS P320/P420 (mA/HART)
Operating Instructions, 06/2018, A5E44852162-AA
159