Emerson Rosemount 644 HART, Reference Manual

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Reference Manual
00809-0100-4728, Rev MB
Configuration
July 2016
Configuration
Using AMS Device Manager
1. Right click on the device and select Service Tools .
2. In the left navigation window select Simulate.
3. In the group box labeled Device Variables choose the variable to simulate.

Sensor 1 Temperature

Sensor 2 Temperature (only available with option S)
4. Follow the screen prompts to simulate selected digital value.
Using Local Operator Interface
Reference the figure below to find the path to the Simulate Digital Signal in the LOI menu.
Figure 2-21. Simulating the Digital Signal with LOI
* Available only if option code (S) is ordered.
2.11.3 Thermocouple Degradation Diagnostic
Thermocouple Degradation Diagnostic acts as a gauge of the general health of the
thermocouple and is indicative of any major changes in the status of the thermocouple or the
thermocouple loop. The transmitter monitors the resistance of the thermocouple loop to
detect drift conditions or wiring condition changes. The transmitter uses a baseline and
threshold Trigger value and reports the suspected status of the thermocouple based off the
difference between these values. This feature is not intended to be a precise measurement of
thermocouple status, but is a general indicator of thermocouple and thermocouple loop health.
Thermocouple diagnostic must be Enabled as well as connected and configured to read a
thermocouple type sensor. Once the diagnostic has been activated, a Baseline Resistance value
is calculated. Then a Trigger threshold must be selected, which can be two, three, or four times
the Baseline resistance, or the default of 5000 ohms. If the thermocouple loop resistance
reaches the Trigger Level, a maintenance alert is generated.
The Thermocouple Degradation Diagnostic monitors the health of the entire thermocouple
loop, including wiring, terminations, junctions, and the sensor itself. Therefore, it is imperative
that the diagnostic baseline resistance be measured with the sensor fully installed and wired in
the process, and not on the bench.
CALIBRAT
DAMPING
VARIABLE MAP
TAG
ALM SAT VALUES
PASSWORD
SIMULATE SIMULATE
HART REV
....
SIMULATE SNSR 1
SIMULATE SNSR 2*
END SIMUL
BACK TO MENU
EXIT MENU
VIEW CONFIG
SENSOR CONFIG
UNITS
RERANGE
LOOP TEST
DISPLAY
EXTENDED MENU EXTENDED MENU
EXIT MENU