Full Calibration; Min/Max Calibration; Two Point Calibration; Weight Calibration - Emerson FISHER FIELDVUE DLC3010 Instruction Manual

Instruction Manual
D102748X012

Full Calibration

Field Communicator Configure > Calibration > Primary > Full Calibration (2-4-1-2)
Full Calibration operations compute the sensor gain and zero reference from two independent observations of process
data points. They are appropriate for cases where the two input conditions can be established relatively quickly in one
session.

Min/Max Calibration

The following procedure can be useful when process values can't be precisely observed, but the displacer can
sequentially be submerged in fluids of known minimum and maximum density. (E.g., no sight glass is available, but the
cage can be isolated and drained or flooded.)
Torque rate and input zero are computed from observed minimum and maximum process conditions, density data,
displacer volume, and driver rod length.
Follow the prompts on the Field Communicator to calibrate the instrument and sensor.
1. Set the control loop for manual control.
2. Enter the specific gravity for the liquid in the system.
3. Adjust the liquid level until the displacer is dry (or completely submerged in upper liquid). Allow the output to
settle, then acknowledge establishment of the minimum buoyancy condition to the system.
4. Adjust the liquid level until the displacer is completely submerged in the lower liquid. Allow the output to settle,
then acknowledge establishment of the maximum buoyancy condition of the system.
The sensor is calibrated. Verify that the upper and lower range values are correct and return the loop to automatic
control.

Two Point Calibration

This procedure uses independent observations of two valid process conditions, together with the hardware
dimensional data and SG information, to compute the effective torque rate and zero reference angle for the sensor.
The two data points can be separated by any span between a minimum of 5% to 100%, as long as they remain on the
displacer. Within this range, the calibration accuracy will generally increase as the data‐point separation gets larger.
Accuracy is also improved by running the procedure at process temperature, as the temperature effect on torque rate
will be captured. (It is possible to use theoretical data to pre‐compensate the measured torque rate for a target
process condition when the calibration must be run at ambient conditions.)
An external method of measuring the process condition is required.
Follow the prompts on the Field Communicator to calibrate the sensor.
1. Put the control loop in manual control.
2. Adjust the process condition to a value near the top or bottom of the valid range.
3. Enter this externally measured process condition in the current PV units.
4. Adjust the process condition to a value near the bottom or top of the valid range, but at a position that is toward the
opposite end of the range relative to the condition used in step 2.
5. Enter this second externally measured process condition in the current PV units.
The sensor is now calibrated. Be sure to verify that the upper and lower range values are correct before returning the
loop to automatic control.

Weight Calibration

This procedure may be used on the bench or with a calibration jig that is capable of applying a mechanical force to the
driver rod to simulate displacer buoyancy changes. It allows the instrument and sensor to be calibrated using
DLC3010 Digital Level Controller
Configuration
May 2018
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