Emerson Rosemount, Справочное руководство

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190
Reference Manual
00809-0100-4021, Rev GC
Section 7: Prior Use (PU) Safety Instrumented System
April 2014
Prior use (PU) safety instrumented system
7.3.3 Proof test
The following proof tests are recommended. In the event that an error is found in the safety
functionality, proof test results and corrective actions taken must be documented at www.rose-
mont.com/safety.
Use Table 3-1: Fast Key Sequences to perform Loop Test, Review – Device Variables, and view
Status.
The required proof test intervals will depend on the transmitter configuration and the
temperature sensor(s) in use. Guidance is available in
Table 6-1: Proof test interval guideline
Refer to the FMEDA report for further information.
Abbreviated proof test
Conducting the abbreviated proof test detects approximately 63% of transmitter DU failures
and approximately 90% of temperature sensor(s) DU failures, not detected by the 3144P
safety-certified automatic diagnostics, for a typical overall assembly coverage of 67%.
1. Using Loop Test, enter the milliampere value representing a high alarm state.
2. Check the reference meter to verify the mA output corresponds to the entered value.
3. Using Loop Test, enter the milliampere value representing a low alarm state.
4. Check the reference meter to verify the mA output corresponds to the entered value.
5. Use a field communicator to view detailed device status to ensure no alarms or
warnings are present in the transmitter.
6. Check that sensor value(s) are reasonable in comparison to a basic process control
system (BPCS) value.
7. Document the test results per the plant’s requirements.
Extended proof test
Conducting the extended proof test, which includes the abbreviated proof test, detects
approximately 96% of transmitter DU failures and approximately 99% of temperature sensor(s)
DU failures, not detected by the 3144P safety-certified automatic diagnostic, for a typical
overall assembly coverage of 96%.
1. Execute the abbreviated proof test.
2. Perform a minimum two point sensor verification check. If two sensors are used, repeat
for each sensor. If calibration is required for the installation, it may be done in
conjunction with this verification.
3. Verify the housing temperature value is reasonable.
4. Document the test results per the plant’s requirements.