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Result
The device is in the "Functional Safety disabled" device mode.
Note
The system shows unexpected data or behaves differently than described in this procedure.
● Repeat the entire procedure.
10.6
Proof test
Proof tests can detect errors in the device that are not detected by the integrated diagnostics
of the device.
Proof tests performed at regular intervals uncover undetected errors that can otherwise cause
safety-related functions to function not as intended.
The interval between two proof tests is dependent on the safety-related system, based on the
combined calculations of failure rates for the system.
10.6.1
Intervals and rules for proof test
To ensure reliable operation of the fail-safe behavior, perform the following proof tests at the
following intervals:
All devices
Read the information on maintenance intervals and checking the seals and cable glands in
the section Maintenance and repair work (Page 177).
Absolute pressure devices
Set the zero point every 5 years for the following variants:
Measuring cell
Absolute pressure from the rela‐
tive pressure/absolute pressure
series with front-flush diaphragm
Absolute pressure from the dif‐
ferential pressure series
250 mbar a/25 kPa a/100 H
2
O
7MF0.2. - .F ... - ....
7MF0.3. - .G ... - ....
1300 mbar a/130 kPa a/525 H
2
O 7MF0.2. - .L ... - ....
7MF0.3. - .L ... - ....
5000 mbar a/500 kPa a/72.5 psi a 7MF0.2. - .P ... - ....
7MF0.3. - .P ... - ....
30 bar a/3 MPa a/435 psi a
7MF0.2. - .R ... - ....
7MF0.3. - .R ... - ....
Functional Safety
10.6 Proof test
SITRANS P320/P420 (mA/HART)
172
Operating Instructions, 06/2018, A5E44852162-AA