Emerson FISHER FIELDVUE DLC3010, Инструкция по эксплуатации

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Instruction Manual
D102748X012
DLC3010 Digital Level Controller
Configuration
May 2018
64
memory during the calibration process should match the SG of the test fluid being used in the calibration. After the
initial calibration, the instrument may be set up for a target fluid with a given specific gravity, or an interface
application, by simple configuration data changes.
1. Run through Guided Setup and verify that all sensor data is correct.
Procedure:
Change the PV mode to Level
If your input observations are going to be made with respect to location of the bottom of the displacer at the
lowest process condition, set the Level Offset value to 0.00, and
Set the Specific Gravity value to the SG of the test fluid being used.
Establish the test fluid level at the desired process zero point. Make sure that the DLC3010 lever assembly has been
properly coupled to the torque tube (see coupling procedure on page 39). To unlock the lever assembly and allow it to
freely follow the input, close the coupling access door on the instrument. It is often possible to watch the instrument
display and/or the analog output to detect when the fluid hits the displacer, because the output will not start moving
upward until that point is reached.
Select the Min/Max calibration from the Full Calibration menu, and confirm that you are at the 'Min' condition at the
prompt. After the 'Min' point has been accepted, you will be prompted to establish the 'Max' condition. (The 'displacer
completely covered' condition should be slightly higher than the 100% level mark to work correctly. for example, 15
inches above the zero mark would generally be enough for a 14 inch displacer on a 249B, because the amount of
displacer rise expected for that configuration is about 0.6 inch.)
Accept this as the 'Max' condition. Adjust the test fluid level and check the instrument display and current output
against external level at several points distributed across the span to verify the level calibration.
a. To correct bias errors, 'Trim Zero' at a precisely known process condition.
b. To correct gain errors, 'Trim Gain' at a precisely­known high level condition.
Note
If you are able to precisely observe individual input states, the Two-Point calibration may be used instead of Min/Max.
If for some reason you are unable to carry out Min/Max or Two Point Calibration, set the lowest process condition and Capture
Zero. Run Trim Gain at a process level of minimum 5% above the Lower Range Value.
If the measured output doesn't come off the low saturation value until the level is considerably above the bottom of
the displacer, it is possible that the displacer is overweight. An overweight displacer will rest on the lower travel stop
until sufficient buoyancy has developed to allow the linkage to move. In that case, use the calibration procedure for
overweight displacers found below.
After the initial calibration:
For a liquid level application — Go to the Sensor Compensation menu and use the 'Enter constant SG' item to configure
the instrument for the target process fluid density.
For an interface level application — Change the PV mode to Interface, verify or adjust the range values presented by the
Change PV mode procedure, and then use 'Enter constant SG' to configure the instrument for the SGs of each of the
target process fluids.
For a liquid density application — Change the PV mode to Density, and establish the desired range values in the 'Change
PV mode' procedure.