Emerson 3051N manual Zero Trim, Typical Zero vs Non-zero-Based Application Illustrations

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Reference Manual

00809-0100-4808, Rev CA June 2008

Rosemount 3051N

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 3051N Absolute pressure transmitters. A zero trim is zero-based, and absolute pressure transmitters reference absolute zero. To correct mounting position effects on a Rosemount 3051N Absolute Pressure Transmitter, perform a low trim within the full sensor trim function. The low trim function provides a “zero” correction similar to the zero trim function but it does not require the input to be zero-based.

FIGURE 2-8. Typical Zero vs.

Non-zero-Based Application

Illustrations.

20 mA Point	20 mA Point
4 mA Point	4 mA Point

NONZERO-BASED

LEVEL APPLICATION

Zero Trim

HART Comm.	1, 2, 3, 3, 1

ZERO-BASED LEVEL	ZERO-BASED FLOW
APPLICATION	APPLICATION

A full trim is a two-point sensor calibration where two end-point pressures are applied, and all output is linearized between them. You should 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 factory-established characterization curve is not changed by this procedure. The trim values allow you to optimize performance over your specified measuring range at the calibration temperature.

To calibrate the sensor with a HART Communicator using the Zero Trim function, perform the following procedure.

1.Vent the transmitter and attach a communicator to the measurement loop.

2.From the communicator menu select 1 Device setup, 2 Diagnostics and service, 3 Calibration, 3 Sensor trim, 1 Zero trim to prepare to adjust the zero trim.

NOTE

The transmitter must be within 3% of true zero (zero-based) in order to calibrate it using the zero trim function.

3.Follow the commands provided by the communicator to complete the adjustment of the zero trim.

2-17

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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 Section Introduction Using this ManualRosemount 3051N Transmitter Functions Overview Safety MessagesSecurity Alarm Level VerificationTransmitter Physical Removal Local Zero and Span Local Keys Configuring Transmitter Alarm and Security Jumper ProcedureElectronics Board Setting the Loop to Manual Wiring Diagrams Bench Hook-up Wiring Diagrams Field Hook-up Process Variables Review Configuration DataCheck Output Basic Setup Sensor TemperatureSet Process Variable Units Set OutputRerange with a Communicator Only RerangeRerange with a Pressure Input Source and a Communicator Span and Zero Adjustment Buttons Diagnostics Service Detailed SetupCalibration Transmitter TestLoop Test Transmitter Bench Calibration Tasks Field Calibration Tasks Calibration Overview Configure the Analog Output ParametersURV Sensor TrimTypical Zero vs Non-zero-Based Application Illustrations Zero TrimDigital Trim Connection Drawing 4-20 mA Transmitters Full TrimRecall Factory Trim Recall Factory Trim- Sensor Trim Digital-to-Analog Trim Using Other ScaleRecall 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 Power Supply Load Limitations WiringEnvironmental Considerations Access Requirements Cover InstallationGrounding the Transmitter Case Troubleshooting Returning Rosemount Products and Materials Symptom Corrective ActionsSeismic Nuclear SpecificationsModel Range Code Hydrostatic Test Pressure Ambient Temperature Effect12 Performance SpecificationsReference Accuracy DriftOverpressure Effect Static Pressure Effect Power Supply Effect Load Effect Mounting Position EffectRange Code Overpressure Effect Range Code Static Pressure Zero Effect1Service Functional SpecificationsTemperature Limits OutputRange Code Minimum Time Constant Tc Including Dead Time Td Span and Zero, Zero Elevation, SuppressionRange Minimum Span Upper URL Lower LRL Pressure12 Maximum WorkingStatic Pressure Limits Overpressure Limits Burst PressurePhysical Specifications Materials of Construction Option Code Description Add Ordering Information Housing Material Conduit Entry Size Configuration InformationMounting Bracket Options Meters optionalDate On Rosemount 3051N Exploded View with Coplanar Process Flange Rosemount 3051N Rosemount 3051N Section Options Overview Safety Messages LCD MeterCustom Meter Configuration Exploded View of the Rosemount 3051N with Optional LCD Meter Installing the MeterRosemount 3051N Error Diagnostic MessagesPress Limit Mounting Brackets OperationTransient Protection Terminal Block T1 Traditional Flange H2Transient Protection Terminal Block T1 Rosemount 3051N Appendix a Hart Communicator Introduction Safety MessagesRosemount 3051N Online Menu Function Hart Fast Key Sequence Connections and Hardware Figure A-3. Rosemount Hart terminal access doorFigure A-4. Bench Hook-up MA Transmitters Action Keys RosemountCommunicator Keys Data Entry Function KeysAlphanumeric and Shift Keys Fast Key Sequence Conventions Fast Key Sequence Example Fast Key SequencesMenus Functions Main MenuOnline Menu Touch Multifunction LED Alphanumeric KeysTouch 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¤