Emerson 3051N manual Zero Effect

Page 32

Rosemount 3051N

Reference Manual

00809-0100-4808, Rev CA June 2008

NOTE

Use a precision resistor for optimum accuracy. If you add a resistor to the loop, ensure that the power supply is sufficient to power the transmitter to a 20 mA output with the additional loop resistance.

Compensating Rosemount 3051N Range 4 and 5 Differential Transmitters for

Line Pressure

Rosemount 3051N Range 4 and Range 5 pressure transmitters require a special calibration procedure when used in differential pressure applications. The purpose of this procedure is to optimize transmitter performance by reducing the effect of static line pressure (Ps) in these applications. Rosemount 3051N differential pressure transmitter ranges 0, 1, 2, and 3 do not require this procedure because the optimization occurs in the sensor. See “Static Pressure Effect” on page 5-3for additional details.

Applying high static pressure to Rosemount 3051N Range 4 and Range 5 pressure transmitters causes a systematic shift in the output. This shift is linear with static pressure; correct it by performing the “Full Trim” on page 2-18,after determining the corrected input values as noted below.

The following specifications show the static pressure effect for Rosemount 3051N Range 4 and Range 5 transmitters used in differential pressure applications:

Zero Effect:

±0.1% of the upper range limit per 1000 psi (6,9 MPa) for line pressures (Ps) from 0 to 2000 psi (0 to 13,8 MPa)

±[0.2 + 0.2 (Ps-2000) / 1000]% of the upper range limit per 1000 psi (6,9 MPa) for line pressures above 2000 psi (13,8 MPa) and ≤ 3626 psi (25 MPa)

Span Effect:

Correctable to ±0.2% of reading per 1000 psi for line pressures from 0 to 3626 psi.

The systematic span shift caused by the application of static line pressure is –1.00% of input reading per 1000 psi for 3051N Range 4 transmitters, and –1.25% of reading per 1000 psi for Range 5 transmitters.

Use the following example to compute corrected input values.

Example

A Rosemount 3051ND4 transmitter will be used in a differential pressure application where the static line pressure is 1200 psi. The transmitter is ranged so that the output is 4 mA at 500 inH2O and 20 mA at 1500 inH2O.

To correct for systematic error caused by high static line pressure, first use the following formulas to determine corrected values for the low trim and high trim.

LTc = LRV + S (LRV) Ps

Where:

LTc =

Corrected Low Trim Value

 

LRV =

Lower Range Value

 

S =

–(Systematic Span shift per specification)

 

Ps =

Static Line Pressure

2-20

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Contents Reference Manual Important Notice -- Errata Rosemount 3051N Return of Material Changes Changes from June 2006 to JuneOld Rosemount 3051N Table of Contents Specifications Reference Data InstallationTroubleshooting Hart Communicator OptionsAppendix a Glossary Index Using this Manual Section IntroductionRosemount 3051N Overview Safety Messages Transmitter FunctionsSecurity Alarm Level VerificationTransmitter Configuring Transmitter Alarm and Security Jumper Procedure Physical Removal Local Zero and Span Local KeysElectronics Board Setting the Loop to Manual Wiring Diagrams Bench Hook-up Wiring Diagrams Field Hook-up Process Variables Review Configuration DataCheck Output Sensor Temperature Basic SetupSet Process Variable Units Set OutputRerange Rerange with a Communicator OnlyRerange with a Pressure Input Source and a Communicator Span and Zero Adjustment Buttons Detailed Setup Diagnostics ServiceCalibration Transmitter TestLoop Test Transmitter Bench Calibration Tasks Field Calibration Tasks Configure the Analog Output Parameters Calibration OverviewSensor Trim URVZero Trim Typical Zero vs Non-zero-Based Application IllustrationsFull Trim Digital Trim Connection Drawing 4-20 mA TransmittersDigital-to-Analog Trim Using Other Scale Recall Factory Trim Recall Factory Trim- Sensor TrimRecall Factory Trim- Analog Output Analog Output TrimZero Effect HTc = URV + S URV Ps Rosemount 3051N Section Installation Rosemount 3051N Typical Installation Flowchart Mechanical Considerations General ConsiderationsSpecial Draft Range Considerations 156 181 16 x 11/4 Bolts for Mounting to 54.1 Transmitter 120 127 66.8 Traditional Flange Option Code H2 Dimensional Drawing Mounting Rosemount 3051N GAS or Liquid Service GAS Service Steam Service Electrical Considerations Process Connections Housing RotationPower Supply Wiring Power Supply Load LimitationsEnvironmental Considerations Access Requirements Cover InstallationGrounding the Transmitter Case Troubleshooting Symptom Corrective Actions Returning Rosemount Products and MaterialsNuclear Specifications SeismicModel Range Code Hydrostatic Test Pressure Performance Specifications Ambient Temperature Effect12Reference Accuracy DriftPower Supply Effect Load Effect Mounting Position Effect Overpressure Effect Static Pressure EffectRange Code Overpressure Effect Range Code Static Pressure Zero Effect1Functional Specifications ServiceTemperature Limits OutputRange Code Minimum Time Constant Tc Including Dead Time Td Span and Zero, Zero Elevation, SuppressionRange Minimum Span Upper URL Lower LRL Maximum Working Pressure12Static Pressure Limits Overpressure Limits Burst PressurePhysical Specifications Materials of Construction Option Code Description Add Ordering Information Configuration Information Housing Material Conduit Entry SizeMounting Bracket Options Meters optionalDate  On Rosemount 3051N Exploded View with Coplanar Process Flange Rosemount 3051N Rosemount 3051N Overview Safety Messages LCD Meter Section OptionsCustom Meter Configuration Installing the Meter Exploded View of the Rosemount 3051N with Optional LCD MeterRosemount 3051N Diagnostic Messages ErrorPress Limit Operation Mounting BracketsTraditional Flange H2 Transient Protection Terminal Block T1Transient Protection Terminal Block T1 Rosemount 3051N Introduction Safety Messages Appendix a Hart CommunicatorRosemount 3051N Online Menu Function Hart Fast Key Sequence Figure A-3. Rosemount Hart terminal access door Connections and HardwareFigure A-4. Bench Hook-up MA Transmitters Action Keys RosemountCommunicator Keys Data Entry Function KeysAlphanumeric and Shift Keys Fast Key Sequences Fast Key Sequence Conventions Fast Key Sequence ExampleMenus Functions Main MenuOnline Menu Touch Alphanumeric Keys Multifunction LEDTouch Screen Multifunction LED Processing IndicationRosemount 3051N Message Description Diagnostic MessagesFast Key Sequences Hot Key options Rosemount 3051N Uploadvariable Rosemount 3051N Rosemount 3051N Glossary Smart Family Index 00809-0100-4808, Rev CA June Security Page ¢00809-0100-4801V¤
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