Specifications; Failure Rate Data - Emerson Rosemount 644 Reference Manual

Section 7: Safety Instrumented Systems (SIS) Certification
April 2015
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Visual inspection
Not required
Special tools
Not required
Product repair
The 644 is repairable by replacement only.
All failures detected by the transmitter diagnostics or by the proof-test must be reported.
Feedback can be submitted electronically at
http://www.emersonprocess.com/rosemount/safety/safetyCertTemp.htm.
7.8

Specifications

The 644 must be operated in accordance to the functional and performance specifications
provided in the Rosemount 644 Product Data Sheet (document number 00813-0100-4728).
7.8.1

Failure rate data

The FMEDA report includes failure rates and common cause Beta factor estimates.
The report is available at http://www2.emersonprocess.com/en-US/brands/rose-
mount/Safety-Products/Pages/index.aspx.
88
Bypass the safety PLC or take other appropriate action to avoid a false trip.
Execute steps 2 through 6 of the Partial proof test (see 7.7.2).
Disconnect Sensor 1 and connect a calibrated sensor simulator in its place.
Using at least 2 simulated temperature points, verify the transmitter output remains
within the required accuracy.
If sensor 2 is used, repeat steps 3 and 4.
Restore sensor connections to the transmitter.
Verify the housing temperature value is reasonable.
Check that sensor value(s) are reasonable in comparison to an independent
measurement, such as basic process control system (BPCS) value.
Restore the loop to full operation. Remove the bypass from the safety PLC or otherwise
restore normal operations.
Document the test results per the plant's requirements.
Safety Instrumented Systems (SIS) Certification
Reference Manual
00809-0200-4728, Rev RA