Emerson 3051N manual General Considerations, Special Draft Range Considerations

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Rosemount 3051N

Reference Manual

00809-0100-4808, Rev CA June 2008

GENERAL CONSIDERATIONS

Special Draft Range Considerations

Measurement accuracy depends upon proper installation of the transmitter and impulse piping. Mount the transmitter close to the process and use a minimum of piping to achieve best accuracy. Keep in mind the need for easy access, personnel safety, practical field calibration, and a suitable transmitter environment. Install the transmitter to minimize vibration, shock, and temperature fluctuation.

Installation

It is best to mount the transmitter with the isolating diaphragms parallel to the ground. Installing the transmitter in this way reduces oil head effect and provides for optimal temperature performance.

Be sure the transmitter is securely mounted. Tilting of the transmitter may cause a zero shift in the transmitter output.

Reducing Process Noise

It is often difficult to isolate the actual process variable from process noise in draft range applications. Pressure fluctuations and air currents can make accurate draft range measurements difficult to obtain.

There are two recommended methods of reducing process noise: output damping and, in gage applications, reference side filtering.

Output Damping

The output damping for the Rosemount 3051ND0 is factory set to 3.2 seconds as a default. If the transmitter output is still noisy, increase the damping time. If faster response is needed, decrease the damping time. Damping adjustment information is available in Section 2: Transmitter Functions.

Reference Side Filtering

MECHANICAL CONSIDERATIONS

In gage applications it is important to minimize fluctuations in atmospheric pressure to which the low side isolator is exposed. One method of reducing fluctuations in atmospheric pressure is to attach a length of tubing to the reference side of the transmitter to act as a pressure buffer. Another method is to plumb the reference side to a chamber that has a small vent to atmosphere. If multiple draft transmitters are being used in an application, the reference side of each device can be plumbed to a chamber to achieve a common gage reference.

IMPORTANT

Install the enclosed pipe plug in unused conduit openings with a minimum of five threads engaged to comply with explosion proof requirements.

The following figures show dimensional drawings and installation examples of the Rosemount 3051N transmitters, including mounting brackets.

NOTE

For Rosemount 3051ND0 and 3051ND1, mount the transmitter solidly to prevent tilting. A tilt in the physical transmitter may cause a zero shift in the transmitter output.

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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 Set Process Variable Units Sensor TemperatureBasic Setup 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 TransmittersRecall Factory Trim- Analog Output Digital-to-Analog Trim Using Other ScaleRecall Factory Trim Recall Factory Trim- Sensor Trim 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 Reference Accuracy Performance SpecificationsAmbient Temperature Effect12 DriftRange Code Overpressure Effect Power Supply Effect Load Effect Mounting Position EffectOverpressure Effect Static Pressure Effect Range Code Static Pressure Zero Effect1Temperature Limits Functional SpecificationsService OutputRange Code Minimum Time Constant Tc Including Dead Time Td Span and Zero, Zero Elevation, SuppressionRange Minimum Span Upper URL Lower LRL Static Pressure Limits Maximum WorkingPressure12 Overpressure Limits Burst PressurePhysical Specifications Materials of Construction Option Code Description Add Ordering Information Mounting Bracket Options Configuration InformationHousing Material Conduit Entry Size 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 Menus Functions Fast Key SequencesFast Key Sequence Conventions Fast Key Sequence Example Main MenuOnline Menu Touch Touch Screen Alphanumeric KeysMultifunction LED 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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