Rosemount 3095FB User manual

www.rosemount.com
Reference Manual
00809-0100-4738, Rev DA
May 2006
Rosemount 3095FB
MultiVariable™Transmitter
with Modbus®Protocol

Rosemount 3095FB
Multivariable™Transmitter with
Modbus™Protocol
Rosemount 3095FB Multivariable Transmitter with Modbus Protocol may be protected by one or more of the
following U.S. Patent Nos. 4,370,890; 4,612,812; 4,791,352; 4,798,089; 4,818,994; 4,833,922; 4,866,435;
4,926,340; 5,028,746; Des. 358,782. MEXICO PATENTADO NO. 154961.
Other U.S. and foreign patents issued and pending.
Rosemount and the Rosemount logotype are registered trademarks of Rosemount Inc.
Coplanar and Multivariable are trademarks of Rosemount Inc.
Hastelloy C-276 is a registered trademark of Cabot Corp.
Microsoft and Windows are registered trademarks of Microsoft Corp.
COVER PHOTO: 3095\063AB.tif
Read this manual before working with the product. For personal and system
safety, and for optimum product performance, make sure you thoroughly
understand the contents before installing, using, or maintaining this product.
Within the United States, Rosemount Inc. has two toll-free assistance numbers.
Customer Central: 1-800-999-9307 (7:00 a.m. to 7:00 p.m. CST)
Technical support, quoting, and order-related questions.
North American 1-800-654-7768 (24 hours a day – Includes Canada)
Response Center: Equipment service needs.
For equipment service or support needs outside the United States, contact your
local Rosemount representative.
The products described in this document are NOT designed for
nuclear-qualified applications.
Using non-nuclear qualified products in applications that require
nuclear-qualified hardware or products may cause inaccurate readings.
For information on Rosemount nuclear-qualified products, contact your local
Rosemount Sales Representative.
SNF-0004
NOTICE
Rosemount 3095FB Software Revision 110
Rosemount 3095FB Configurator User Interface Software Revision 2.00
Reference Manual
00809-0100-4738, Rev DA
May 2006 Rosemount 3095FB
www.rosemount.com

Reference Manual
00809-0100-4738, Rev DA
May 2006
TOC-1
Rosemount 3095FB
SECTION 1
Introduction
Using This Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Section 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Section 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Section 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Section 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Section 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Appendix A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Appendix B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Appendix C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
SECTION 2
Installation
Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
General Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
Mechanical Considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
Environmental Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
Installation Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
Review Installation Considerations . . . . . . . . . . . . . . . . . . . . . . . . 2-4
Mount the Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
Process Connections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-9
Consider Housing Rotation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11
Set Jumpers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11
RTD Assembly (Optional) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-13
Connect Wiring and Power Up . . . . . . . . . . . . . . . . . . . . . . . . . . 2-16
Hazardous Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-19
Grounding the Transmitter Case . . . . . . . . . . . . . . . . . . . . . . . . . 2-19
Rosemount 305 Integral Manifold. . . . . . . . . . . . . . . . . . . . . . . . . . . 2-20
Integral Manifold Installation Procedure . . . . . . . . . . . . . . . . . . . 2-20
Integral Manifold Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-21
SECTION 3
Modbus
Communication
Suggestions and Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
SECTION 4
Operation
Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
Installation and Initial Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
Navigation & Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3
Menu Categories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
Hot Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
Calibration Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
Bench Configuration (Standard) . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5
Bench Calibration Procedure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5
Field Calibration Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5
User Interface Software Screens . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6
File Menu. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6
Setup Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6
Table of Contents

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TOC-2
Rosemount 3095FB
Transmitter Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-15
Maintenance Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-16
Diagnostics Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-20
View Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-22
Help Menu. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-22
SECTION 5
Troubleshooting
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-1
Warnings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-1
Communication problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2
Alarms and Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2
Disassembly Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-5
Remove the transmitter from Service . . . . . . . . . . . . . . . . . . . . . . .5-6
Remove the Terminal Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-6
Remove the Electronics Board . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-6
Removing the Sensor Module from the Electronics Housing . . . . .5-7
Reassembly Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-8
Attach the Electronics Board. . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-10
Install the Terminal Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-10
Reassembling the Process Sensor Body . . . . . . . . . . . . . . . . . . . 5-10
APPENDIX A
Specifications and
Reference Data
Functional Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1
Performance Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-2
Differential Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-2
Absolute / Gage Pressure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-3
Process Temperature (RTD). . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-3
Physical Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-4
Dimensional Drawings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-5
Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-7
Spare Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-9
Options. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-12
Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-12
APPENDIX B
Product
Certifications
Approved Manufacturing Locations . . . . . . . . . . . . . . . . . . . . . . . . . . B-1
European Directive Information . . . . . . . . . . . . . . . . . . . . . . . . . . B-1
Hazardous Locations Certifications . . . . . . . . . . . . . . . . . . . . . . . . . . B-1
North American Certifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1
European Certifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-2
Approval Drawings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-3
Factory Mutual (FM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-3
Canadian Standards Association (CSA) . . . . . . . . . . . . . . . . . . . . B-6
APPENDIX C
3095FB Modbus
Integration Guide
General Protocol Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-1
Process Variable Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-2
Other Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-2

Reference Manual
00809-0100-4738, Rev DA
May 2006 Rosemount 3095FB
www.rosemount.com
Section 1 Introduction
USING THIS MANUAL This manual provides installation, configuration, calibration, troubleshooting,
and maintenance instructions for the Rosemount®3095FB Multivariable™
Transmitter with Modbus™Protocol and for its operation with the Rosemount
3095FB Configurator User Interface Software. This manual consists of the
following chapters:
Section 2 Installation
• Install the 3095FB
• Installation flowchart
• Transmitter configuration data
• Installation considerations
• Field installation
• Options and accessories
Section 3 RTU Communication
Rosemount 3095FB Modbus Protocol Guide, Revision F.
Section 4 Operation
• How to use the configuration software
• Installing the software onto a personal computer
• Establishing communications
• Configuring the transmitter
• Creating a configuration file
• Calibrating the transmitter
• Explains each configurator software menu
Section 5 Transmitter Maintenance and Troubleshooting
• Troubleshooting instructions for dealing with potential mechanical or
electrical difficulties.
Section 6 Specifications and Reference Data
• Specification data
• Spare parts information
Appendix A Approvals
• Factory Mutual (FM) certified drawings
• Canada Standards Association (CSA) certified drawings.
Appendix B Product Certifications
Appendix C MODBUS Integration Guide

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Rosemount 3095FB
1-2

Reference Manual
00809-0100-4738, Rev DA
May 2006 Rosemount 3095FB
www.rosemount.com
Section 2 Installation
OVERVIEW The information in this section covers installation considerations for the
3095FB MultiVariable Transmitter with Modbus protocol. A Quick Installation
Guide (document number 00825-0100-4738) is shipped with every transmitter
to describe basic pipe-fitting and wiring procedures for initial installation.
SAFETY MESSAGES Procedures and instructions in this section may require special precautions to
ensure the safety of the personnel performing the operation. Review all safety
messages covered in this manual before continuing with the operation.
Warnings
Explosions can result in death or serious injury.
• Do not remove the transmitter covers in explosive environments when the circuit is
live.
• Fully engage both transmitters covers to meet explosion-proof requirements.
• Verify that the operating atmosphere of the transmitter is consistent with the
appropriate hazardous locations certifications.
Electrical shock can result in death or serious injury.
• Avoid contact with the leads and terminals.
Process leaks could result in death or serious injury.
• Install and tighten all four flange bolts before applying pressure.
• Do not attempt to loosen or remove flange bolts while the transmitter is in service.
Replacement equipment or spare parts not approved by Rosemount, Inc. for use as
spare parts could reduce the pressure retaining capabilities of the transmitter and may
render the instrument dangerous.
• Use only bolts supplied or sold by Rosemount, Inc. as spare parts.

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Rosemount 3095FB
2-2
GENERAL
CONSIDERATIONS
Measurement accuracy depends upon proper installation of the transmitter
and impulse piping. Mount the transmitter close to the process and use
minimal impulse 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.
IMPORTANT
Install the enclosed pipe plug in unused conduit openings with a minimum of
five threads engaged to comply with Explosion-Proof requirements. The
transmitter is shipped with the plug installed on transmitters ordered with CSA
Explosion-Proof approval.
MECHANICAL
CONSIDERATIONS
“Dimensional Drawings” beginning on page A-5 show dimensional drawings.
Figure 2-4 on page 2-9 shows installation examples.
NOTE
For steam service or for applications with process temperatures greater than
the limits of the transmitter, do not blow down impulse piping through the
transmitter. Flush lines with the blocking valves closed and refill lines with
water before resuming measurement.
NOTE
When the transmitter is mounted on its side, position the Coplanar flange to
ensure proper venting or draining. Mount the flange as shown in Figure 2-4 on
page 2-9, keeping drain/vent connections on the bottom for gas service and
on the top for liquid service.
ENVIRONMENTAL
CONSIDERATIONS
The following guidelines can help optimize transmitter performance. Mount
the transmitter to minimize ambient temperature changes, vibration,
mechanical shock, and external contact with corrosive materials. Appendix A:
Range and Sensor Limits on page A-1 lists the transmitter temperature
operating limits.
Improper assembly of manifolds to traditional housing can damage sensor module.
• For safe assembly of manifold to traditional flange, bolts must break back plane of
flange web (i.e. bolt hold) but must not contact module housing.

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May 2006
2-3
Rosemount 3095FB
INSTALLATION
PROCEDURES
Figure 2-1 details the full procedure for installing a new 3095FB.
Figure 2-1. Rosemount 3095FB Installation Flowchart
A
B
B
START
A
B
Unpack the
Rosemount
3095FB
Review the
3095FB Product
Manual
Bench
Configure
?
BENCH
CONFIGURE
Connect Bench
Power Supply
Connect Personal
Computer
Perform Bench
Configuration
Tasks
(Optl.) Perform
Bench Calibration
Tasks
FIELD
INSTALLATION
Review Installation
Considerations
Mount
Transmitter and
Install Bolts
(Optional) Install
RTD Assembly
Make Field Wiring
Connections
DONE
Yes
No
(Optl.) Perform
Field Calibration
Tasks
Bench
Configuration
Performed
?
No Perform
Configuration
Tasks
Yes
Review Appendix B
Hazardous
Location
?
Yes
No

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May 2006
Rosemount 3095FB
2-4
Review Installation
Considerations
When choosing an installation location and position, take into account the
need for access to the transmitter. For dimensional drawing information see
page A-6.
Process Flange Orientation
Mount the process flanges with sufficient clearance for process connections.
For safety reasons, place the drain/vent valves so the process fluid is directed
away from you when the vents are used. In addition, consider the possible
need for a testing or calibration input.
Housing Rotation
See “Consider Housing Rotation” on page 2-11.
Terminal Side of Electronics Housing
Mount the transmitter so that the terminal side is accessible. A 0.75-inch (19
mm) clearance is required for cover removal. Use a conduit plug on the
unused side of the conduit opening.
Circuit Side of Electronics Housing
Provide 0.75 inches (19 mm) clearance if possible for cover removal. Three
inches of clearance is required for cover removal if a display is installed.
Cover Installation
Always install the electronics housing covers metal-to-metal to ensure a
proper seal.

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Rosemount 3095FB
2-5
Mount the Transmitter Figure 2-2 illustrates a typical 3095 installation site. Major components of the
installation are identified in these figures.
Figure 2-2. Typical Rosemount 3095FB Installation Site
The 3095FB transmitter total weight varies depending on the components
ordered (see Table 2-1). This weight must be securely supported.
Table 2-1. Transmitter Weight
Mounting Brackets
Optional mounting brackets available with the 3095FB facilitate mounting to a
panel, wall, or 2-inch pipe. The bracket option for use with the Coplanar flange
is 316 SST with 316 SST bolts. Figure 2-3 shows bracket dimensions and
mounting configurations for this option. When installing the transmitter to one
of the mounting brackets, torque the bolts to 125 in-lb.
3095FB
RTD Connector
Process
Connections
RTD Cable
RTD Assembly
Conduit Opening
for Connections
to RTU and
Power Supply
3095-3095f22a
Flow
Component Weight
3095FB Without Options 6 lb (2,7 kg)
LCD Meter for Aluminum Housing 0.5 lb (0,2 kg)
SST Mounting Bracket for Coplanar Flange 1.0 lb (0,5 kg)
12 ft (3,66 m) cable 0.5 lb (0,2 kg)
24 ft (7,32 m) cable 2.2 lb (1,0 kg)

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2-6
NOTE
Most transmitters are calibrated in the horizontal position. Mounting the
transmitter in any other position will shift the zero point to the equivalent
amount of liquid head caused by the varied mounting position. To reset zero
point, refer to “Sensor Trim” on page 4-16.
Mounting Bolts
The following guidelines have been established to ensure a tight flange,
adapter, or manifold seal. Use only bolts supplied with the transmitter or sold
by Rosemount Inc. as a spare part to the Rosemount 3095FB transmitter.
The Rosemount 3095FB is shipped with the Coplanar flange installed with
four 1.75-inch flange bolts. The following bolts also are supplied to facilitate
other mounting configurations:
• Four 2.25-inch manifold/flange bolts for mounting the Coplanar flange
on a three-valve manifold. In this configuration, the 1.75-inch bolts may
be used to mount the flange adapters to the process connection side of
the manifold.
• (Optional) If flange adapters are ordered, four 2.88-inch flange/adapter
bolts for mounting the flange adapters to the Coplanar flange.
Figure 2-3 shows the optional mounting bracket and mounting configurations.
Stainless steel bolts supplied by Rosemount Inc. are coated with a lubricant to
ease installation. Carbon steel bolts do not require lubrication. No additional
lubricant should be applied when installing either type of bolt. Bolts supplied
by Rosemount Inc. are identified by their head markings:

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Rosemount 3095FB
2-7
Figure 2-3. Optional Mounting Brackets and Mounting Configurations
1.75 (44) x 4
2.25 (57) x 4
TRANSMITTER WITH 3-VALVE MANIFOLD
MANIFOLD/FLANGE BOLTS
FLANGE ADAPTERS
AND FLANGE/ADAPTER BOLTS
NOTE
Dimensions are in inches (millimeters)
Description Qty.
Size
in. (mm)
Flange bolts
Flange/adapter bolts
Manifold/flange bolts
4
4
4
1.75 (44)
2.88 (73)
2.25 (57)
2.88 (73) x 4
TRANSMITTER WITH
OPTIONAL FLANGE ADAPTERS
AND FLANGE/ADAPTER BOLTS
TRANSMITTER WITH
FLANGE BOLTS
1.75 (44) x 4
3095-3095D05M, 3095C05A, fieldbus\3095\3095a29A

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2-8
Mounting Requirements
Refer to figure 2-4 for examples of the following mounting considerations:
Liquid Flow Measurement
• Place taps to the side of the line to prevent sediment deposits on the
transmitter’s process isolators.
• Mount the transmitter beside or below the taps so gases can vent into
the process line.
• Mount drain/vent valve upward to allow gases to vent.
Gas Flow Measurement
• Place taps in the top or side of the line.
• Mount the transmitter beside or above the taps so liquid will drain into
the process line.
Steam Flow Measurement
• Place taps to the side of the line.
• Mount the transmitter below the taps to ensure that the impulse piping
will stay filled with condensate.
• Fill impulse lines with water to prevent the steam from contacting the
transmitter directly and to ensure accurate measurement start-up.
NOTE
In steam or other elevated temperature services, it is important that
temperatures at the coplanar process flanges not exceed 250 °F (121 °C) for
transmitters with silicone fill or 185 °F (85 °C) for inert fill.

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2-9
Figure 2-4. Example Installations
Process Connections The 3095 process connections on the transmitter flange are 1/4–18 NPT.
Flange adapter unions with 1/2–14 NPT connections are available as options.
These are Class 2 threads; use your plant-approved lubricant or sealant when
making the process connections. The process connections on the transmitter
flange are on 21/8-inch (54-mm) centers to allow direct mounting to a three- or
five-valve manifold. By rotating one or both of the flange adapters, connection
centers of 2, 21/8, or 21/4inches (51, 54, or 57 mm) may be obtained.
Install and tighten all four flange bolts before applying pressure or process
leakage will result. When properly installed, the flange bolts will protrude
through the top of the module housing. Do not attempt to loosen or remove
the flange bolts while the transmitter is in service.
Flow
Flow
3095\3095b03b, 3095d03b
GAS SERVICE
LIQUID SERVICE
Flow
STEAM
SERVICE

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2-10
To install adapters to a Coplanar flange, perform the following procedure:
1. Remove the flange bolts.
2. Leaving the flange in place, move the adapters into position with the
O-ring installed.
3. Clamp the adapters and the Coplanar flange to the transmitter
module using the larger of the bolts supplied.
4. Tighten the bolts. Refer to “Mounting Bolts” on page 2-6 for torque
specifications.
When compressed, Teflon® O-rings tend to cold flow, which aids in their
sealing capabilities. Whenever you remove flanges or adapters, visually
inspect the Teflon O-rings. Replace them if there are any signs of damage,
such as nicks or cuts. If they are undamaged, you may reuse them. If you
replace the O-rings, retorque the flange bolts after installation to compensate
for cold flow.
Impulse Piping
The piping between the process and the transmitter must accurately transfer
the pressure to obtain accurate measurements. There are five possible
sources of error: pressure transfer, leaks, friction loss (particularly if purging is
used), trapped gas in a liquid line, liquid in a gas line, and density variations
between the legs.
Failure to install proper flange adapter O-rings can cause process leaks, which can
result in death or serious injury.
The two flange adapters are distinguished by unique O-ring grooves. Only use the
O-ring that is designed for its specific flange adapter, as shown below.
Refer to the Spare Parts list on page A-9 for the correct part numbers of the flange
adapters and O-rings designed for Rosemount 3051 transmitters.
3051-0569A01A
ROSEMOUNT 1151
ROSEMOUNT 3051S/ 3051/3001/3095/2024
Flange Adapter
O-ring
Flange Adapter
O-ring
Elastomer
Teflon
Elastomer
Teflon Based
3051S 3051C 2024

Reference Manual
00809-0100-4738, Rev DA
May 2006
Rosemount 3095FB
2-11
The best location for the transmitter in relation to the process pipe depends on
the process itself. Use the following guidelines to determine transmitter
location and placement of impulse piping:
• Keep impulse piping as short as possible.
• For liquid service, slope the impulse piping at least 1 inch per foot (8
cm per m) upward from the transmitter toward the process connection.
• For gas service, slope the impulse piping at least 1 inch per foot (8 cm
per m) downward from the transmitter toward the process connection.
• Avoid high points in liquid lines and low points in gas lines.
• Make sure both impulse legs are the same temperature.
• Use impulse piping large enough to avoid friction effects and blockage.
• Vent all gas from liquid piping legs.
• When using a sealing fluid, fill both piping legs to the same level.
• When purging, make the purge connection close to the process taps
and purge through equal lengths of the same size pipe. Avoid purging
through the transmitter.
• Keep corrosive or hot (above 250 °F [121 °C]) process material out of
direct contact with the sensor module and flanges.
• Prevent sediment deposits in the impulse piping.
• Keep the liquid head balanced on both legs of the impulse piping.
• Avoid conditions that might allow process fluid to freeze within the
process flange.
Consider Housing
Rotation
The electronics housing can be rotated up to 180 degrees (left or right) to
improve field access or to better view the optional LCD display. To rotate the
housing, perform the following procedure:
1. Loosen the housing rotation set screw using a 5/64-in. hex wrench.
2. Turn the housing up to 180 degrees to the left or right of its original
(as shipped) position. Do not rotate the housing more than 180
degrees without first performing a disassembly procedure (see
“Disassembly Procedures” on page 5-5). Over-rotation will sever the
electrical connection between the sensor module and the electronics
module.
3. Retighten the housing rotation set screw.
Set Jumpers Security
You can prevent changes to the transmitter configuration data with the write
protection jumper. Security is controlled by the security (write protect) jumper
located on the electronics board or display face. Position the jumper on the
transmitter circuit board in the “ON” position to prevent accidental or
deliberate change of configuration data.
If the transmitter write protection jumper is in the “ON” position, the transmitter
will not accept any “writes” to its memory. Configuration changes, such as
digital trim and reranging, cannot take place when the transmitter security is
on.
AC Termination (AC)
The RS-485 bus needs to be terminated once at both ends, and should not be
terminated elsewhere on the bus. Setting the AC TERMINATION (AC) switch
to ON provides AC bus termination.

Reference Manual
00809-0100-4738, Rev DA
May 2006
Rosemount 3095FB
2-12
NOTE
The RTU may already provide one RS-485 bus termination.
Pull-down (B) and Pull-up (A)
These switches are used to put the RS-485 bus into the idle state. Set these
switches either to both ON (idle state), or to both OFF (lets the bus float). If a
transmitter has multiple communication errors, set these switches to ON (idle
state).
NOTE
Only one device on an RS-485 bus should set the bus to the idle state. In
some installations, the RTU might maintain the bus in the idle state when the
RS-485 bus is inactive.
Baud Rate (S1 and S2)
Table 2-2 identifies four available baud rates for RS-485 Modbus
communications.
Table 2-2. Baud Rate Settings
Configuring RS485 and Security Jumpers
When shipped from the factory, the RS-485 switches are all set to off, and the
baud rate switches are set to 9600 (see Table 2-2).
To reposition the jumpers, follow the procedure described below.
1. If the transmitter is installed, remove power.
2. Remove the housing cover opposite the field terminal side. Do not
remove the transmitter covers in explosive atmospheres when the
circuit is live.
3. Remove the LCD meter if present.
4. Locate the switches on the output electronics board (see Figure 2-5),
and then move the switch to the desired setting.
5. Reattach the transmitter cover. Transmitter covers must be fully
engaged to meet Explosion-Proof requirements.
S1 S2 Baud Rate
OFF OFF 1200
ON OFF 2400
OFF ON 4800
ON ON 9600