Emerson 1154, 00809-0100-4514 manual Calculate zero adjustment correction in terms of pressure

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Reference Manual

00809-0100-4514, Rev BA January 2008

Rosemount 1154

1.Calibrate the unit per preceding section to output = 4 mA at –100 inH2O and 20 mA at 300 inH2O.

2.Calculate correction factor:

0.75 %

------------------------ × 1, 200 psi= 0.9% differential input

1,000 psi

3. Calculate zero adjustment correction in terms of pressure:

0.9 % × –100 inH2O = –0.9 inH2O

4. Convert pressure correction to percent of input span:

–0.9 inH2O

---------------------------------------------------------------= –0.225 % span

400 inH2O input span

5. Calculate correction in terms of output span (mA):

–0.225 % × 16 mA span = – 0.036 mA

6. Add the milliamp correction to the ideal zero output (4 mA). This is the corrected ideal zero output:

4.00 mA – 0.036 = 3.964 mA

7. Calculate full-scale adjustment correction in terms of pressure:

0.9% × 300 inH2O = 2.7 inH2O

8.Repeat step 4 with the results of step 7:

2.7 inH2O

---------------------------------------------------------------= 0.675 % span

400 inH2O input span

9. Repeat step 5 with the result of step 8:

0.675 % × 16 mA span = 0.108 mA

10. Add the mA correction to the ideal full-scale output (20 mA). This is the corrected ideal full-scale output:

20.00 mA + 0.108 mA = 20.108 mA

11. Readjust zero and span adjustments for corrected outputs:

3.964 mA at –100 inH2O

20.108 mA at 300 inH2O

There is an uncertainty of ±0.5 percent of input reading per 1,000 psi associated with the span correction.

Zero

Zero shift with static pressure is not systematic. However, if the calibrated range includes zero differential pressure, the effect can be trimmed out after installation and with the unit at operating pressure.

3-7

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Contents Reference Manual RosemountImportant Notice -- Errata Rosemount 1154 Alphaline Nuclear Pressure Transmitter Return of Material New Old Changes Revision StatusChanges From June 1999 to January Rosemount Table of Contents Section Maintenance TroubleshootingSpecifications Reference Data TOC-3 TOC-4 Overview About the Transmitter Section IntroductionRosemount Overview General Considerations Section InstallationProcess Connections Mechanical ConsiderationsRosemount Electrical Considerations ConduitTransmitter Wiring Connections Mechanical InstallationProcedures Range Code Pressure DimensionElectrical Liquid ServiceTransmitter Terminal Block Rosemount Overview Calibration Span Adjustment Zero AdjustmentSection Calibration Zero and Span Adjustment Calibration ProceduresZero and Span Adjustment Screws Linearity Adjustment Linearity and Damping Adjustment Damping AdjustmentRosemount Calculate zero adjustment correction in terms of pressure Rosemount Overview Transmitter Operation Section OperationΔ-Cell Demodulator Linearity AdjustmentFV Iref Overview Maintenance TroubleshootingTest Terminals Board Checkout Safety MessagesSensing Module Checkout Process Flange Removal Disassembly ProcedurePart Description Rosemount 1154 Parts ListReassembly Procedure Rosemount Process Flange Reassembly On Next Post Assembly TestsSymptom Potential Source Corrective Action Check for adequate voltage to the transmitter Nuclear Specifications Specifications and Reference DataPerformance Specifications Range Code Overpressure Effect Range Code Response Time Functional SpecificationsRange Code Static Pressure Zero Effect 25 to 0-150 inH2O 0-6.22 to 0-37.3 kPa Range Code Pressure RangesRange Code Overpressure Limit Physical SpecificationsRosemount Ordering Information Rosemount 1154DP 1154HP 1154GP Part Description Order No Rosemount 1154DP, 1154HP, and 1154GP Spare PartsFor use with existing N0026 transmitter only Spare Parts Shelf Life Important Notice Rosemount Current Control Current Limit Index-2 Page ¢00809-XXXX-XXXX ¤
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