
8.7
Perform proof test for SIS applications
8.7.1
Overview
The following proof tests are recommended. If an error is found in the safety function, the
measuring system must be switched out of service and the process held in a safe state by
means of other measures.
The following proof-tests are suggested:
•
Suggested comprehensive proof-test
•
(B)
Suggested comprehensive, fully remote proof-test
•
•
(D)
Suggested comprehensive proof-test using reference reflector (High Level
•
(E)
Suggested comprehensive, fully remote proof-test using reference reflector (High
•
Suggested proof-test using reference reflector (High Level Supervision)
•
Suggested fully remote proof-test using reference reflector (High Level
can be used as a guidance for selecting the appropriate proof-test.
Table 8-4: Suggested Proof-tests
Proof-
test #
Type
Proof-test coverage
(%) of DU
Remaining dangerous,
undetected failures
Can be performed
remotely
A
Comprehensive
94%
6 FIT
No
B
Comprehensive
85%
14 FIT
Yes
C
Partial
55%
43 FIT
Yes
D
Comprehensive
94%
6 FIT
No
E
Comprehensive
86%
13 FIT
Yes
F
Comprehensive
82%
17 FIT
No
G
Comprehensive
74%
25 FIT
Yes
Note
For a valid result, always perform the proof test on the product that will be stored in the
tank while the device is in operation.
Note
Before every test, make sure you are connected to the correct transmitter by verifying
QT/QS in the model code on the label and your software version. Also verify that the serial
number on the label matches the one in your configuration tool. Make sure to enable write
protection as soon as you are finished.
Reference Manual
Safety Instrumented Systems (4-20 mA only)
00809-0100-4530
April 2019
Reference Manual
251