Emerson Rosemount 248 Reference Manual page 20

Configuration
April 2024
a known temperature source. Sensor trimming is suitable for validation procedures or for
applications that require calibrating the sensor and transmitter together.
To perform a sensor trim with a transmitter:
Procedure
1. Connect the calibration device or sensor to the transmitter. Refer to
2. Connect the communicator to the transmitter.
3. From the Home screen, select Service Tools → Maintenance → Calibration to prepare
4. Select one:
5. Answer the prompt about configuring device for steady state sensor drive.
6. Select the appropriate sensor trim units at the prompt.
7. Adjust the calibration device to the desired trim value (must be within the selected
8. After the temperature has stabilized, select OK. The communicator displays the
9. Accept new calibration.
AMS Device Manager
For AMS Device Manager, configure the sensor as indicated above.
Procedure
1. From the Overview screen, select the Calibrate button.
2. Select Lower Input Trim or Upper Limit Trim. The wizard will continue through the
3. To restore the transmitter to factory default, select Service Tools → Maintenance →
4. Apply changes.
2.4.6 Configuring the LCD display
The LCD display configuration command allows customization of the LCD to suit
application requirements. The LCD will alternate between the selected items:
• Temperature Units
• Sensor Temperature
20
the device terminal block for sensor wiring diagrams.
to trim the sensor.
• 6 Lower Sensor Trim
• 7 Upper Sensor Trim
Note
Emerson recommends performing lower offset trims first and upper slope trims
second.
sensor limits).
If a combined sensor and transmitter system are being trimmed, expose the sensor
to a known temperature and allow the temperature reading to stabilize. Use a bath,
furnace or isothermal block, measured with a site-standard thermometer, as the
known temperature source.
output value the transmitter associates with the input value provided by the
calibration device.
process.
Sensor Calibration → Recall Factory Trim. The wizard will revert the transmitter to
the factory trim for a given sensor.
Reference Manual
00809-0100-4248
Figure 2-1 or on
Emerson.com/Rosemount