Emerson Rosemount 248 User manual

Reference Manual
00809-0100-4825, Rev CB
March 2014
Rosemount®248 Temperature Transmitter

v
Reference Manual
00809-0100-4825, Rev CB
Rosemount 248 Temperature
Transmitter
Rosemount 248 Hardware Revision
Headmount
Railmount
HART®Device Revision
Field Communicator Field Device Revision
4
1
5.1
Dev v1, DD v1
NOTICE
Read this manual before working with the product. For personal and system safety, and for
optimum product performance, make sure to thoroughly understand the contents before
installing, using, or maintaining this product.
The United States has two toll-free assistance numbers and one international number.
Customer Central
1 800 999 9307 (7:00 a.m. to 7:00 P.M. CST)
National Response Center
1 800 654 7768 (24 hours a day)
Equipment service needs
International
1 952 906 8888
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 an Emerson Process
Management Sales Representative.

vii
Reference Manual
00809-0100-4825, Rev CB
Table of Contents
March 2014
Table of Contents
Content
1Section 1: Introduction
1.1 Safety messages. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
1.1.1 Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
1.2 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
1.2.1 Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
1.2.2 Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
1.3 Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
1.3.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
1.3.2 Commissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
1.3.3 Mechanical. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
1.3.4 Electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
1.3.5 Environmental. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
1.4 Return of materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
1.5 Product recycling/disposal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
2Section 2: Installation
2.1 Safety messages. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
2.1.1 Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
2.2 Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
2.3 Installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
2.3.1 Typical European and Asia Pacific installation . . . . . . . . . . . . . . . . . . . . . . . .10
2.3.2 Typical North and South American installation. . . . . . . . . . . . . . . . . . . . . . .11
2.4 Multichannel installations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
2.5 Set the switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
2.5.1 Failure mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
2.6 Wiring. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
2.6.1 Sensor connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
2.7 Power supply. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
2.7.1 Surges/transients . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
2.7.2 Ground the transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
3Section 3: Configuration
3.1 Safety messages. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
3.1.1 Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
3.2 Commissioning. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
3.2.1 Setting the loop to manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24

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3.3 AMS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
3.3.1 Apply AMS changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
3.4 Field communicator. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
3.4.1 HART traditional menu tree . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
3.4.2 HART device dashboard menu tree. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
3.4.3 Fast Key sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
3.4.4 Review configuration data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
3.4.5 Check output. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
3.4.6 Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
3.4.7 Information variables. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
3.4.8 Diagnostics and service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
3.5 Multidrop communication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
3.6 Rosemount 248 Configuration Interface specifications . . . . . . . . . . . . . . . . . . . . .40
3.6.1 Configuration software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
3.6.2 Configuration hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
3.6.3 Rosemount 248 PC Programmer Kit installation . . . . . . . . . . . . . . . . . . . . .41
4Section 4: Operation and maintenance
4.1 Safety messages. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43
4.1.1 Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43
4.2 Calibration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44
4.2.1 Trim the transmitter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44
4.3 Hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
4.3.1 Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
4.4 Diagnostic messages. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47
4.4.1 Hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47
4.4.2 Field communicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49
AAppendix A: Specifications and reference data
A.1 Transmitter specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51
A.1.1 Functional specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51
A.1.2 Physical specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
A.1.3 Performance specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54
A.2 Sensor specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57
A.2.1 Thermocouples – IEC 584 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57
A.2.2 Thermocouples – ASTM E- 230 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .58
A.2.3 RTDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .58
A.2.4 Thermowells . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59

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A.3 Dimensional drawings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60
A.4 Ordering information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62
BAppendix B: Product Certifications
B.1 Approved Manufacturing Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65
B.2 European Directive Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65
B.3 Ordinary Location Certification from FM Approvals . . . . . . . . . . . . . . . . . . . . . . . .65
B.3.1 North America. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65
B.3.2 Europe. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66
B.3.3 International . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68
B.3.4 China . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69
B.3.5 Combinations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71
B.3.6 Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72
B.4 Installation drawings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72

Reference Manual
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Section 1: Introduction
March 2014
1
Introduction
Section 1 Introduction
Safety messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 1
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2
Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 3
Return of materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 5
Product recycling/disposal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 5
1.1 Safety messages
Instructions and procedures in this section may require special precautions to ensure the safety
of the personnel performing the operations. Information that potentially raises safety issues is
indicated by a warning symbol ( ). Please refer to the following safety messages before
performing an operation preceded by this symbol.
1.1.1 Warnings
Failure to follow these installation guidelines could result in death or
serious injury.
Make sure only qualified personnel perform the installation.
Explosions could result in death or serious injury.
Do not remove the connection head cover in explosive atmospheres when the
circuit is live.
Before connecting a Field Communicator in an explosive atmosphere, make sure the
instruments in the loop are installed in accordance with intrinsically safe or
non-intrinsic field wiring practices.
Verify that the operating atmosphere of the transmitter is consistent with the
appropriate hazardous locations certifications.
All connection head covers must be fully engaged to meet
explosion-proof requirements.
Process leaks could result in death or serious injury.
Do not remove the thermowell while in operation.
Install and tighten thermowells and sensors before applying pressure
Electrical shock could cause death or serious injury.
Use extreme caution when making contact with the leads and terminals.

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Section 1: Introduction
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Introduction
1.2 Overview
1.2.1 Manual
This manual is designed to assist in the installation, operation, and maintenance of the
Rosemount 248 Temperature Transmitter.
Section 1: Introduction
Transmitter and Manual Overview
Things to considerations
How to return the transmitter
Section 2: Installation
How to mount the transmitter
How to Install the transmitter
How to set the switches to ensure proper use
How to wire and power up the transmitter
Section 3: Configuration
Commissioning to transmitter
How to use the Field Communicator to configure the transmitter
Section 4: Operation and maintenance
Calibration the transmitter
Explanation of hardware maintenance and diagnostic messages
Appendix A: Specifications and reference data
Transmitter and Sensor Specifications
Dimensional drawings
Ordering Information
Appendix B: Product Certifications
Product Certifications/Hazardous Locations Certifications
Installation Drawings
1.2.2 Transmitter
Features of the Rosemount 248 include:
Acceptance of inputs from a wide variety of RTD and thermocouple sensors
Configuration using HART protocol
Electronics encapsulated in epoxy and enclosed in a plastic housing, making the
transmitter extremely durable and ensuring long-term reliability
A compact size and three housing options that allow mounting flexibility in the field

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Section 1: Introduction
March 2014
Introduction
Refer to the following literature for sensors, thermowells, and extensions that form a complete
point solution with the Rosemount 248:
Temperature Sensors and Assemblies Product Data Sheet, Volume 1 (Document No.
00813-0100-2654)
Temperature Sensors and Assemblies Product Data Sheet, Volume 2 (Document No.
00813-0200-2654)
Temperature sensors and Assemblies Product Data Sheet, Volume 3 (Document No.
00813-0301-2654)
1.3 Considerations
1.3.1 General
Electrical temperature sensors, such as RTDs and thermocouples, produce low-level signals
proportional to the sensed temperature. The Rosemount 248 converts the low-level sensor
signal to a standard 4–20 mA dc signal that is relatively insensitive to lead length and electrical
noise. This current signal is transmitted to the control room through two wires.
1.3.2 Commissioning
The transmitter may be commissioned before or after installation. It can be useful to
commission it on the bench, before installation, to ensure proper operation and to become
familiar with its functionality. The instruments in the loop should be installed according to the
intrinsically safe or non-incendive field wiring practices before connecting a Field
Communicator in an explosive atmosphere. For more information, see “Commissioning” on
page 24.
1.3.3 Mechanical
Location
When choosing an installation location, take into account access to the transmitter.
Special mounting
Special hardware is available for mounting a Rosemount 248 head mount transmitter to a DIN
rail.
1.3.4 Electrical
Proper electrical installation is necessary to prevent errors from sensor lead resistance and
electrical noise. For best results, shielded cable should be used in electrically noisy
environments. A resistance between 250 and 1100 ohms must be present in the loop for
communication with a Field Communicator.
Make wiring connections through the cable entry in the side of the connection head being sure
to provide adequate clearance for cover removal.

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Section 1: Introduction
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Introduction
1.3.5 Environmental
The transmitter electronics module is permanently sealed within the housing, to resist moisture
and corrosive damage. Verify that the operating atmosphere of the transmitter is consistent
with the appropriate hazardous locations certifications.
Temperature effects
The transmitter operates within specifications for ambient temperatures between –40 and 185
°F (–40 and 85 °C). Process heat from the process is transferred from the thermowell to the
transmitter housing so if the expected process temperature is near or above specification limits,
consider using an additional thermowell lagging, and extension nipple, or a remote mounting
configuration to isolate the transmitter from the process.
Figure 1-1 provides an example of the relationship between transmitter housing temperature
rise and extension length.
Figure 1-1. Rosemount 248 Transmitter Connection Head Temperature rise vs. Extension
Length
Example
The transmitter specification limit is 85 °C. If the ambient temperature is 55 °C and the process
temperature to be measured is 800 °C, the maximum permissible connection head temperature
rise is the transmitter specification limit minus the ambient temperature (moves 85 to 55 °C), or
30 °C.
In this case, an extension of 100 mm meets this requirement, but 125 mm provides a margin of
8 °C, reducing any temperature effects in the transmitter.
60
50
40
30
20
10
0
75 10 125 150 175 200 225
Temperature rise above ambient (°C)
Extension length (mm)
815°C
process
temperature
540°C
process
temperature
250°C
process
temperature

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Section 1: Introduction
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Introduction
1.4 Return of materials
To expedite the return process in North America, call the Emerson Process Management
National Response Center toll-free at 800-654-7768. This center is available 24 hours a day and
will assist you with any needed information or materials.
The center will ask for the following information:
Product model
Serial numbers
The last process material to which the product was exposed
The center will provide
A Return Material Authorization (RMA) number
Instructions and procedures that are necessary to return goods that were exposed to
hazardous substances
Note
If a hazardous substance is identified, a Material Safety Data Sheet (MSDS), required by law to be
available to people exposed to specific hazardous substances, must be included with the
returned materials.
Outside North America, contact a local Emerson Process Management representative.
1.5 Product recycling/disposal
Recycling of equipment and packaging should be taken into consideration and disposed of in
accordance with local and national legislation/regulations.

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Section 2: Installation
March 2014
7
Installation
Section 2 Installation
Safety messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 7
Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 9
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 10
Set the switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 14
Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 15
Power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 18
2.1 Safety messages
Instructions and procedures in this section may require special precautions to ensure the safety
of the personnel performing the operations. Information that potentially raises safety issues is
indicated by a warning symbol ( ). Please refer to the following safety messages before
performing an operation preceded by this symbol.
2.1.1 Warnings
Failure to follow these installation guidelines could result in death or
serious injury.
Make sure only qualified personnel perform the installation.
Explosions could result in death or serious injury.
Do not remove the connection head cover in explosive atmospheres when the
circuit is live.
Before connecting a communicator in an explosive atmosphere, make sure the
instruments in the loop are installed in accordance with intrinsically safe or
non-incendive field wiring practices.
Verify that the operating atmosphere of the transmitter is consistent with the
appropriate hazardous locations certifications.
All connection head covers must be fully engaged to meet
explosion-proof requirements.
Process leaks could result in death or serious injury.
Do not remove the thermowell while in operation.
Install and tighten thermowells and sensors before applying pressure
Electrical shock could cause death or serious injury.
Use extreme caution when making contact with the leads and terminals.

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Section 2: Installation
March 2014
Installation
Figure 2-1. Installation Flowchart
START
HERE
Bench
calibration
BASIC SETUP
Set Sensor type
Set Number of wires
Set Units
Set Range values
Set Damping
VERIFY
Simulate Sensor input
Within
Specifications
Refer to Section 4: Operation and
maintenance
FIELD INSTALL
Mount transmitter
Wire transmitter
Power transmitter
FINISHED

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Reference Manual
00809-0100-4825, Rev CB
Section 2: Installation
March 2014
Installation
2.2 Mounting
Mount the transmitter at a high point in the conduit run to prevent moisture from draining into
the transmitter housing.
The Rosemount 248R installs directly to a wall or to a DIN rail.
The Rosemount 248H installs:
In a connection head or universal head mounted directly on a sensor assembly
Apart from a sensor assembly using a universal head
To a DIN rail using an optional mounting clip
Mounting a Rosemount 248H to a DIN rail
To attach a head mount transmitter to a DIN rail, assemble the appropriate rail mounting kit
(part number 00248-1601-0001) to the transmitter as shown in Figure 2-2.
Figure 2-2. Assembling Rail Clip Hardware to a Rosemount 248
A. Mounting hardware
B. Transmitter
C. Rail clip
B
A
C

10
Reference Manual
00809-0100-4825, Rev CB
Section 2: Installation
March 2014
Installation
2.3 Installation
The Rosemount 248 can be ordered assembled to a sensor and thermowell or as a stand-alone
unit. If ordered without the sensor assembly, use the following guidelines when installing the
transmitter with an integral sensor assembly.
2.3.1 Typical European and Asia Pacific installation
Head mount transmitter with DIN plate style sensor
1. Attach the thermowell to the pipe or process container wall then install and tighten the
thermowell before applying process pressure.
2. Assemble the transmitter to the sensor. Push the transmitter mounting screws through
the sensor mounting plate and insert the snap rings (optional) into the transmitter
mounting screw groove.
3. Wire the sensor to the transmitter (see “Sensor wiring Diagrams” on page 16).
4. Insert the transmitter-sensor assembly into the connection head. Thread the
transmitter mounting screw into the connection head mounting holes and assemble
the extension to the connection head then insert the assembly into the thermowell.
5. Slip the shielded cable though the cable gland
6. Attach a cable gland into the shielded cable.
7. Insert the shielded cable leads into the connection head through the cable entry then
connect and tighten the cable gland.
8. Connect the shielded power cable leads to the transmitter power terminals making
sure to avoid contact with sensor leads and sensor connections.
9. Install and tighten the connection head cover making sure the enclosure covers are fully
engaged to meet explosion-proof requirements.
A. Rosemount 248 transmitter D. Transmitter mounting screws
B. Connection head E. Integral mount sensor with flying leads
C. Thermowell F. Extension
A
D
B
C
EF

11
Reference Manual
00809-0100-4825, Rev CB
Section 2: Installation
March 2014
Installation
2.3.2 Typical North and South American installation
Head mount transmitter with threaded sensor
1. Attach the thermowell to the pipe or process container wall then install and tighten
thermowells before applying process pressure.
2. Attach necessary extension nipples and adapters to the thermowell making sure to seal
the nipple and adapter threads with silicone tape.
3. Twist the sensor into the thermowell and install drain seals, if required, for severe
environments or to satisfy code requirements.
4. Pull the sensor wiring leads through the universal head and transmitter. Mount the
transmitter in the universal head by threading the transmitter mounting screws into
the universal head mounting holes.
5. Mount the transmitter-sensor assembly into the thermowell sealing the adapter
threads with silicone tape.
6. Install conduit for field wiring to the conduit entry of the universal head making sure to
seal the conduit threads with silicone tape.
7. Pull the field wiring leads through the conduit into the universal head. Attach the sensor
and power leads to the transmitter. Avoid contact with other terminals.
8. Install and tighten the universal head cover. Enclosure covers must be fully engaged to
meet explosion-proof requirements.
A. Threaded thermowell D. Universal head
B. Threaded style sensor E. Conduit entry
C. Standard extension
AB
C
D
E

12
Reference Manual
00809-0100-4825, Rev CB
Section 2: Installation
March 2014
Installation
Rail mount transmitter with integral mount sensor
The least complicated assembly uses:
an integral mount sensor with terminal block
an integral DIN style connection head
a standard extension
a threaded thermowell
Refer to the Metric Product Data Sheet (Document No. 00813-0101-2654) for complete sensor
and mounting accessory information.
To complete the assembly:
1. Attach the transmitter to a suitable rail or panel.
2. Attach the thermowell to the pipe or process container wall. Install and tighten the
thermowell before applying pressure.
3. Attach the sensor to the connection head and mount the entire assembly to the
thermowell.
4. Attach sufficient lengths of sensor lead wire to the sensor terminal block.
5. Attach and tighten the connection head cover. Enclosure covers must be fully engaged
to meet explosion-proof requirements.
6. Run sensor lead wires from the sensor assembly to the transmitter.
7. Attach the sensor and power leads to the transmitter. Avoid contact with leads and
terminals.
Figure 2-3. Typical Rail Mount Transmitter Mounting Configuration using integral
Mount Sensor and Assembly
A. Rail mount transmitter D. Connection head
B. Sensor leads with cable gland E. Standard extension
C. Integral mount sensor with terminal block F. Threaded thermowell
C
D
E
F
A
B