Emerson Rosemount 644 with HART Protocol, Reference Manual

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Reference Manual
00809-0200-4728, Rev SA
Configuration
July 2018
Configuration
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 select the variable to simulate.
a. Sensor 1 Temperature
b. Sensor 2 Temperature (only available with option S or D)
4. Follow the screen prompts to simulate selected digital value.
LOI
Reference the Figure 2-20 to find the path to the simulate digital signal in the LOI menu.
Figure 2-20. Simulating the Digital Signal with LOI
* Available only if option code (S) or (D) 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.
Note
The thermocouple resistance algorithm does not calculate resistance values while the active calibrator
mode is enabled.
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