Emerson Rosemount 248 User manual

Reference Manual
00809-0100-4825, Rev DA
May 2019
Rosemount™ 248 Temperature Transmitter

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 am to 7:00 pm CST)
National Response Center 1 800 654 7768 (24 hours a day) Equipment service needs
International 1 952 906 8888
CAUTION
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™ Sales Representative.
WARNING
Failure to follow these installation guidelines could result in death or serious injury.
Ensure only qualified personnel perform the installation.
Explosions could result in death or serious injury.
Do not remove the housing covers in explosive atmospheres when the circuit is live.
Before connecting a handheld communicator in an explosive atmosphere, ensure the instruments 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.
Physical access
Unauthorized personnel may potentially cause significant damage to and/or misconfiguration of end users’ equipment. This
could be intentional or unintentional and needs to be protected against.
Physical security is an important part of any security program and fundamental to protecting your system. Restrict physical
access by unauthorized personnel to protect end users’ assets. This is true for all systems used within the facility.
2

Contents
Chapter 1 Introduction.................................................................................................................. 5
1.1 Using this Manual............................................................................................................................. 5
1.2 Transmitter overview....................................................................................................................... 5
1.3 Product recycling/disposal................................................................................................................7
Chapter 2 Installation.....................................................................................................................9
2.1 Safety messages...............................................................................................................................9
2.2 Confirm HART revision capability......................................................................................................9
2.3 Switch HART® revision mode.......................................................................................................... 10
2.4 Considerations............................................................................................................................... 10
2.5 Mounting....................................................................................................................................... 13
2.6 Installing the transmitter................................................................................................................14
2.7 Multichannel installations...............................................................................................................19
2.8 Set the switches............................................................................................................................. 19
2.9 Wiring............................................................................................................................................ 20
2.10 Power supply................................................................................................................................24
Chapter 3 Configuration...............................................................................................................29
3.1 Safety messages.............................................................................................................................29
3.2 Commissioning.............................................................................................................................. 29
3.3 AMS Device Manager......................................................................................................................30
3.4 Field Communicator.......................................................................................................................31
3.5 Multidrop communication..............................................................................................................42
3.6 Rosemount 248 Configuration Interface specifications.................................................................. 43
Chapter 4 Operation and Maintenance.........................................................................................45
4.1 Safety messages.............................................................................................................................45
4.2 Calibration......................................................................................................................................45
4.3 Transmitter-sensor matching......................................................................................................... 47
4.4 Switching HART Revision................................................................................................................ 49
4.5 Hardware Maintenance.................................................................................................................. 50
4.6 Diagnostic messages......................................................................................................................50
Chapter 5 Safety Instrumented Systems (SIS) Requirements.........................................................55
5.1 SIS certification...............................................................................................................................55
5.2 Identify safety certification............................................................................................................. 55
5.3 Installation..................................................................................................................................... 55
5.4 Configuration................................................................................................................................. 56
5.5 OperationandMaintenance.............................................................................................................56
5.6 Specifications................................................................................................................................. 58
Appendix A Reference Data.............................................................................................................59
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A.1 Product Certifications.....................................................................................................................59
A.2 Ordering Information, Specifications, and Drawings...................................................................... 59
Contents Reference Manual
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1 Introduction
1.1 Using this Manual
This manual is designed to assist in the installation, operation, and maintenance of the
Rosemount™ 248 Temperature Transmitter.
Introduction
•Manual overview
•Transmitter overview
Installation
•Things to considerations
•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
Configuration
•Commissioning to transmitter
•How to use the Field Communicator to configure the transmitter
Operation and Maintenance
•Calibration the transmitter
•Explanation of hardware maintenance and diagnostic messages
•How to return the transmitter
Reference Data
•Product Certifications/Hazardous Locations Certifications
•Specifications
•Dimensional drawings
•Ordering Information
1.2 Transmitter overview
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
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•IEC 61508:2010 safety certification
•A compact size and multiple housing options that allow mounting flexibility in the field
•Improve measurement accuracy with Transmitter-Sensor matching.
Refer to the following literature for a full range of compatible connection heads, sensors,
and thermowells provided by Emerson:
•Rosemount 214C Temperature Sensors Product Data Sheet
•Rosemount Volume 1 Temperature Sensors and Accessories (English) Product Data
Sheet
•Rosemount DIN-Style Temperature Sensors and Thermowells (Metric) Product Data
Sheet
Table 1-1 and 1-2 below summarize changes in the 248 headmount and railmount HART
device revisions, respectively.
Table 1-1: Headmount HART Revisions
Software
release date
Identify device Field device driver Review
instructions
NAMUR
software
revision
NAMUR
hardware
revision(1)
HART
universal
revision(2)
Device
revision
Manual document
number
Jun 2019 1.0.1. 1.0.2 7 7.4.11(3) 00809-0100-4825
5 5.2.11(3)
Dec 2005 N/A N/A 5 5.2.2.
(1) NAMUR Software Revision is located in the hardware tag of the device. HART Software Revision
can be read using a HART capable configuration tool.
(2) Device Driver file names use Device and DD Revision, e.g. 10_07. HART Protocol is designed to
enable legacy driver revisions to continue to communicate with new HART devices. To access this
functionality, the new device driver must be downloaded. It is recommended to download the
new device driver to ensure new functionality.
(3) HART 5 and 7 Selectable, CVD sensor matching.
Table 1-2: Railmount HART Revisions
Software
release date
Identify device Field device driver Review
instructions
NAMUR
software
revision
NAMUR
hardware
revision(1)
HART
universal
revision(2)
Device
revision
Manual document
number
Mar 2005 N/A N/A 5 5.2.1. 00809-0100-4825
(1) NAMUR Software Revision is located in the hardware tag of the device. HART Software Revision
can be read using a HART capable configuration tool.
(2) Device Driver file names use Device and DD Revision, e.g. 10_07. HART Protocol is designed to
enable legacy driver revisions to continue to communicate with new HART devices. To access this
functionality, the new device driver must be downloaded. It is recommended to download the
new device driver to ensure new functionality.
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1.3 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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2 Installation
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.
WARNING
Failure to follow these installation guidelines could result in death or serious
injury.
Ensure only qualified personnel perform the installation.
Explosions could result in death or serious injury.
Do not remove the housing covers in explosive atmospheres when the circuit is live.
Before connecting a handheld communicator in an explosive atmosphere, ensure
the instruments 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.
2.2 Confirm HART revision capability
If using HART® based control or asset management systems, confirm the HART Protocol
capability of those systems prior to transmitter installation. Not all systems are capable of
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communicating with HART Revision 7. This transmitter can be configured for either HART
Revision 5 or Revision 7.
2.3 Switch HART® revision mode
If the HART Protocol configuration tool is not capable of communicating with HART
Revision 7, the transmitter will load a generic menu with limited capability. The following
procedures will switch the HART Revision mode from the generic menu:
Procedure
Select Manual Setup → Device Information → Identification → Message.
a) To change to HART Revision 5, enter HART5 in the Message field.
b) To change to HART Revision 7, enter HART7 in the Message field.
2.4 Considerations
2.4.1 General
Electrical temperature sensors, such as RTDs and thermocouples, produce low-level
signals proportional to the sensed temperature. The Rosemount™ 248 Temperature
Transmitter converts the low-level sensor signal to a HART 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.
2.4.2 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.
2.4.3 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.
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2.4.4 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.
2.4.5 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)(1). 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
Note
Extended ranges available with BR5 and BR6 option codes for extending the lower ambient
temperature limit to –50 and –60 °C, respectively.
Figure 2-1 provides an example of the relationship between transmitter housing
temperature rise and extension length.
Figure 2-1: Rosemount 248 Transmitter Connection Head Temperature rise vs.
Extension Length
(1) Extended ranges available with BR5 and BR6 option codes.
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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.
2.4.6 Installation Flowchart
Figure 2-2: Installation Flowchart
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2.5 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
2.5.1 Mounting a Rosemount 248H to a DIN rail
Procedure
•To attach a head mount transmitter to a DIN rail, assemble the appropriate rail
mounting kit (part number 00248-1601-0001) .
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Figure 2-3: Assembling Rail Clip Hardware to a Rosemount 248
C
B
A
A. Mounting hardware
B. Transmitter
C. Rail clip
2.6 Installing the transmitter
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.
2.6.1 Typical European and Asia Pacific installation
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Head mount transmitter with DIN plate style sensor
Procedure
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 connections).
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.
Example
Figure 2-4: European and Asia Pacific installation diagram
A. Rosemount 248 transmitter
B. Connection head
C. Thermowell
D. Transmitter mounting screws
E. Integral mount sensor with flying leads
F. Extension
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2.6.2 Typical North and South American installation
Head mount transmitter with threaded sensor
Procedure
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.
Example
Figure 2-5: North and South American installation diagram
A. Threaded thermowell
B. Threaded style sensor
C. Standard extension
D. Universal head
E. Conduit entry
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
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•a standard extension
•a threaded thermowell
Refer to the appropriate Product Data Sheet regarding Emerson temperature elements for
complete sensor and mounting accessory information.
To complete the assembly:
Procedure
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.
Example
Figure 2-6: Typical Rail Mount Transmitter Mounting Configuration using integral
Mount Sensor and Assembly
A. Rail mount transmitter
B. Sensor leads with cable gland
C. Integral mount sensor with terminal block
D. Connection head
E. Standard extension
F. Threaded thermowell
Rail mount transmitter with threaded sensor
The least complicated assembly uses:
•a threaded sensor with flying heads
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•a threaded sensor connection head
•a union and nipple extension assembly
•a threaded thermowell
Refer to the appropriate Product Data Sheet regarding Emerson temperature elements for
complete sensor and mounting accessory information.
To complete the assembly:
Procedure
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 necessary extension nipples and adapters. Seal the nipple and adapter
threads with silicone tape.
4. Twist the sensor into the thermowell. Install drain seals if required for severe
environments or to satisfy code requirements.
5. Screw the connection head to the sensor.
6. Attach the sensor lead wires to the connection head terminals.
7. Attach additional sensor lead wires from the connection head to the transmitter.
8. Attach and tighten the connection head cover. Enclosure covers must be fully
engaged to meet explosion-proof requirements.
9. Attach the sensor and power leads to the transmitter. Avoid contact with leads and
terminals.
Example
Figure 2-7: Typical Rail Mount Transmitter Mounting Configuration using Threaded
Style Sensor and Assembly
A. Rail mount transmitter
B. Threaded sensor connection head
C. Threaded style sensor
D. Standard extension
E. Threaded thermowell
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2.7 Multichannel installations
Several transmitters can be connected to a single master power supply, as shown in Figure
2-8. In this case, the system may be grounded only at the negative power supply terminal.
In multichannel installations, where several transmitters are dependent on one power
supply and the loss of all transmitters would cause operational problems, consider an
uninterrupted power supply or a back-up battery. The diodes shown in Figure 2-8 prevent
unwanted charging or discharging of the back-up battery.
Figure 2-8: Multichannel Installations
A. Transmitter no. 1
B. Transmitter no. 2
C. RLead
D. Readout or Controller no. 1
E. Readout or Controller no. 2
F. Backup battery
G. dc Power supply
H. To additional transmitters
2.8 Set the switches
2.8.1 Failure mode
Each transmitter continuously monitors its performance during normal operation with an
automatic diagnostic routine of continuous timed series of checks. If an input sensor
failure or a transmitter electronics failure is detected, the transmitter outputs the low or
high alarm, depending on the failure mode configuration. For sensor temperature outside
of range limits:
Standard saturation levels:
•3.90 mA on the low end
•20.5 mA on the high end
NAMUR compliant saturation levels:
•3.80 mA on the low end
•20.5 mA on the high end
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These values are also custom configurable by the factory or using the Field Communicator
or AMS Device Manager. See for instructions on how to change the alarm and saturation
levels with the Field Communicator.
Note
Microprocessor failures cause high alarm regardless of alarm direction (high or low)
choice.
The values the transmitter drives its output in failure mode depend on if it is configured to
standard, NAMUR-compliant, or custom operation.
2.9 Wiring
All power to the transmitter is supplied over the signal wiring. Ordinary copper wire of
sufficient size should be used to ensure the voltage across the transmitter power terminals
does not drop below 12.0 Vdc. Verify that the operating atmosphere of the transmitter is
consistent with the appropriate hazardous locations certifications. Always use extreme
caution when making contact with the leads and terminals.
If the sensor is installed in a high-voltage environment and a fault condition or installation
error occurs, the sensor leads and transmitter terminals could carry lethal voltages. Use
extreme caution when making contact with the leads and terminals.
CAUTION
Do not apply high voltage (e.g., ac line voltage) to the transmitter terminals since high
voltage can damage the unit. (Sensor and transmitter power terminals are rated up to
42.4 Vdc.) Use extreme caution when making contact with the leads and terminals.
For multichannel installations, see Multichannel installations. The transmitters accept
inputs from a variety of RTD and thermocouple types. Refer to Figure 2-10 when making
sensor connections.
Use the following steps to wire the transmitter:
Procedure
1. Remove the terminal block cover (if applicable).
2. Connect the positive power lead to the “+” terminal. Connect the negative power
lead to the “–” terminal (see Figure 2-9). Use extreme caution when making contact
with the leads and terminals.
3. Tighten the terminal screws.
4. Reattach and tighten the cover (if applicable). All connection head covers must be
fully engaged to meet explosion-proof requirements.
5. Apply power (see Power supply).
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