Commissioning And Recurring Tests; Proof Test Of The Transmitter's Complete Signal Processing Chain - WIKA T32.1S Sicherheitshandbuch

2. Safety

2.8 Commissioning and recurring tests

The operability and error signalling current of the model T32.xS temperature transmitter
must be tested both during commissioning and at appropriate intervals. Both the nature
of the testing as well as the chosen intervals are the responsibility of the user. The interval
usually conforms to the PFD
EN
Appendix 1: "SIL declaration of conformity"). Normally the proof test takes place every year.
The PFD value conforms almost linearly to the proof test interval, T
avg
the available PFD
system, the proof test interval can be increased or decreased.

2.8.1 Proof test of the transmitter's complete signal processing chain

1. If required, bypass the safety controller system or take the appropriate action to prevent
an alarm being triggered unintentionally, respectively.
2. Deactivate the instrument's write protection
3. With the aid of the HART
alarm value (≥ 21.0 mA) (HART
4. Test whether the current output signal reaches this value.
5. With the aid of the function in simulation mode, set the current output of the transmitter
to a low alarm value (≤ 3.6 mA).
6. Test whether the current output signal reaches this value.
7. Activate the write protection and wait for a minimum of 5 seconds.
8. Switch the instrument off, or disconnect from the power supply.
9. Restart the instrument and wait at least 15 seconds from the switch-on time.
10. Check the current output with reference temperature
select (4 mA to +20 % of the span) and for the final value (20 mA up to -20 % of the
span).
11. When using a customer-specific characteristic curve, this must be checked at a
minimum of three points.
12. Remove the bypass on the safety controller system or restore the normal operating
condition in a different way.
13. Following the tests, the results must be documented and archived accordingly.
1) Checking transmitters without sensors can also be achieved with an appropriate sensor simulator
(simulator, ref. voltage sources, etc.). Here the sensor must be tested to the SIL demands of the
customer's application. The measuring or setting accuracy of the test instruments used should be at least
0.2 % of the span of the current output (16 mA).
With the testing described above, a diagnostic coverage of 99 % will be
achieved.
14
value given in the standard (for values and key data see
avg
value for the "sensor" system component of the safety instrumented
avg
function in simulation mode, set the current output to a high
®
command 40: Enter fixed current mode).
®
at 2 points. For the initial value
1)
WIKA safety manual temperature transmitter T32.xS
. Depending on
proof