Specifications

81
Reference Manual
00809-0100-4001, Rev JA
Section 4: Operation and Maintenance
November 2012
Operation and maintenance
AMS Device Manager
Right click on the device and select Calibrate, then Recall Factory Trim from the menu.
1. Click Next after setting the control loop to manual.
2. Select Analog output trim under Trim to recall and click Next.
3. Click Next to acknowledge restoration of trim values is complete.
4. Select Next to acknowledge the loop can be returned to automatic control.
5. Select Finish to acknowledge the method is complete.
4.5 Sensor trim
4.5.1 Sensor trim overview
Trim the sensor using either sensor or zero trim functions. Trim functions vary in complexity and
are application-dependent. Both trim functions alter the transmitter’s interpretation of the
input signal.
Zero trim is a single-point offset adjustment. It is useful for compensating for mounting position
effects and is most effective when performed with the transmitter installed in its final mounting
position. Since this correction maintains the slope of the characterization curve, it should not be
used in place of a sensor trim over the full sensor range.
When performing a zero trim, ensure that the equalizing valve is open and all wet legs are filled
to the correct levels.
Note
Do not perform a zero trim on Rosemount 3051T Absolute pressure transmitters. Zero trim is
zero based, and absolute pressure transmitters reference absolute zero. To correct mounting
position effects on a 3051T Absolute Pressure Transmitter, perform a low trim within the sensor
trim function. The low trim function provides an offset correction similar to the zero trim
function, but it does not require zero-based input.
Sensor trim is a two-point sensor calibration where two end-point pressures are applied, and all
output is linearized between them. Always adjust the low trim value first to establish the correct
offset. Adjustment of the high trim value provides a slope correction to the characterization
curve based on the low trim value. The trim values allow you to optimize performance over your
specified measuring range at the calibration temperature.