Emerson Rosemount 644 Reference Manual page 90

Operation and Maintenance
March 2021
5.4.3 Recall factory trim—sensor trim
The recall factory trim—sensor trim feature allows the restoration of the as-shipped factory
settings of the analog output trim. This command can be useful for recovering from an
inadvertent trim, incorrect Plant Standard or faulty meter.
Recall factory trim using a Field Communicator
From the HOME screen, enter the Fast Key sequence and follow the steps within the Field
Communicator to complete the sensor trim.
Device Dashboard Fast Keys
Recall factory trim using AMS Device Manager
Procedure
1. Right click on the device and select Service Tools.
2. On the Sensor Calibration tab, select the Restore Factory Calibration.
3. Follow the screen prompts through the restoring of the calibration settings.
Recall factory trim using LOI
Reference
Figure 5-3: Recalling the Sensor Trim with the LOI
VIEW CONFIG
SENSOR CONFIG
UNITS
RERANGE
LOOP TEST
DISPLAY
EXTENDED MENU
EXIT MENU
5.4.4 Active calibrator and EMF compensation
The transmitter operates with a pulsating sensor current to allow EMF compensation and
detection of open sensor conditions. Because some calibration equipment requires a
steady sensor current to function properly, the "Active Calibrator Mode" feature should be
used when an Active Calibrator is connected. Enabling this mode temporarily sets the
transmitter to provide steady sensor current unless two sensor inputs are configured.
Disable this mode before putting the transmitter back into the process to set the
transmitter back to pulsating current. "Active Calibrator Mode" is volatile and will
automatically be disabled when a master reset is performed (through HART) or when the
power is cycled.
90
Figure 5-3 for where to find recall sensor trim in the LOI menu.
CALIBRAT
DAMPING
VARIABLE MAP
TAG
ALM SAT VALUES
PASSWORD
....
3, 4, 4, 2
SENSOR 1 CALIB
SENSOR 2 CALIB*
ANALOG TRIM
FACTORY RECALL
BACK TO MENU
EXIT MENU
....
Reference Manual
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