Specifications

173
Reference Manual
00809-0100-4026, Rev HA
Section 8: Safety Instrumented Systems (4-20 mA Only)
November 2014
Safety Instrumented Systems (4-20 mA Only)
Proof test
This test detects approximately 95 % of the possible Dangerous Undetected (DU) failures of the
transmitter. Note that prior to conducting the test, the echo curve should be inspected to
ensure that no disturbing echoes affecting the measurement performance are present in the
tank.
Required Tools: HART host/communicator and mA meter.
1. Bypass the logic solver or take other appropriate actions to avoid false trip.
2. Disable write protection if the function is enabled.
3. Using Loop Test, enter the mA value representing a high alarm current output and
verify that the analog current reaches that value using the mA meter.
This step tests for compliance voltage problems, such as low loop power supply voltage or
increased wiring resistance.
4. Using Loop Test, enter the mA value representing a low alarm current output and verify
that the analog current reaches that value using the reference meter.
This step tests for possible quiescent current related failures.
5. Perform a two-point calibration check of the transmitter by adjusting the product level
in two points in the measuring range
(1)
. Verify that the current output corresponds to
the level input values using a known reference measurement.
This step verifies that the analog output is correct in the operating range and that the
Primary Variable is properly configured.
6. Enable write protection.
7. Restore the loop to full operation.
8. Remove the bypass from the safety logic solver or otherwise restore normal operation.
9. Document the test result for future reference.
For troubleshooting the transmitter, see Section 7: Service and Troubleshooting.
8.6.2 Inspection
Visual inspection
It is recommended to inspect the antenna for possible build up or clogging.
Special tools
Not required.
Product repair
The Rosemount 5400 Series is repairable by major component replacement. All failures
detected by the transmitter diagnostics or by the proof test must be reported. Feedback can be
submitted electronically at www.emersonprocess.com/rosemount/safety (Contact Us).
(1) For best performance, use the 4-20 mA range points as calibration points.