744
Documenting Process Calibrator
HART Mode Users Guide
®
PN 691292
December 1998
© 1998 Fluke Corporation, All rights reserved. Printed in U.S.A.
All product names are trademarks of their respective companies.
Table of Contents
Title Page
Introduction..................................................................................................................... 1
How to Contact Fluke ..................................................................................................... 2
Connecting to a HART Transmitter ................................................................................ 3
Supported vs. Generic Transmitters............................................................................... 6
Communication Operations............................................................................................ 8
Viewing Process Variables ........................................................................................ 8
Setup Operations....................................................................................................... 8
Basic ..................................................................................................................... 8
Sensor................................................................................................................... 10
Device Identification.............................................................................................. 10
HART Output ........................................................................................................ 11
HART Information................................................................................................. 11
Service Operations .................................................................................................... 12
Abort Softkey ............................................................................................................. 12
Interaction between Analog Mode and HART Mode...................................................... 12
Understanding HART Calibration................................................................................... 13
744 HART Mode Menus for Adjustment......................................................................... 13
i
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HART Mode Users Guide
Index
Calibrating a Supported HART Transmitter .................................................................... 15
Loop Test.................................................................................................................... 16
Output Trim................................................................................................................. 17
Sensor Trim................................................................................................................ 17
Cloning a Transmitter...................................................................................................... 19
ii
List of Tables
Table Title Page
1. Supported vs. Non-Supported Instruments............................................................................ 7
iii
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HART Mode Users Guide
iv
List of Figures
Figure Title Page
1. Connecting to a HART Transmitter........................................................................................ 5
2. 744 HART Mode Menu Tree.................................................................................................. 9
3. Block Diagram of a HART Transmitter .................................................................................. 14
v
744
HART Mode Users Guide
vi
Documenting Process Calibrator HART Mode
Introduction
w Warning
To avoid electric shock, read the Safety
Information in the
you use the Fluke 744 Documenting Process
Calibrator.
With analog transmitters, you must make a hardware
adjustment during calibration. With HART
Addressable Remote Transducer) transmitters,
adjustments are by remote command. These adjustments
require the use of a communication tool as well as a
calibrator. The Fluke 744, hereafter called “calibrator,”
provides communication and calibration functions in one
tool.
744 Users Manual
before
(Highway-
This manual describes how to use HART mode, which is
active when the calibrator is communicating over its serial
HART interface to a HART transmitter. Refer to the
744 Users Manual
instructions, specifications, and other general information.
All of the calibrator functions described in the
Manual
transmitters. The only transmitters addressed in this
manual are HART transmitters.
are available and can be used with HART
for safety, analog mode operating
744 Users
1
744
HART Mode Users Guide
How to Contact Fluke
To contact Fluke, call:
USA and Canada:
1-888-99-FLUKE (1-888-993-5853)
Europe: +31 402-678-200
Japan: +81-3-3434-0181
Singapore: +65Anywhere in the world: +1-425-356-5500
Or visit us on the World Wide Web: www.fluke.com
-276-6196
*
2
Documenting Process Calibrator HART Mode
Connecting to a HART Transmitter
Connecting to a HART Transmitter
To connect to and begin to communicate with a HART
transmitter, refer to Figure 1 and proceed as follows:
Note
If you only want a communication connection to
a transmitter that is powered in a loop, simply
clip the HART alligator clips to the loop power
r
terminals on the transmitter, press
are done.
1. Connect the calibrator mA jacks to the loop power
terminals of the transmitter.
2. Plug the HART interface cable into the SERIAL
PORT, then connect the alligator clips to the same
terminals as in step 1. There is no right or wrong
polarity.
3. Press the r key.
Note
The square-root symbol on r key is there
only for calculator mode. At all other times, there
is no square-root function associated with the
r
key.
, and you
4. If the transmitter is not powered by a loop power
supply, press the
loop power.
The calibrator provides loop power through an
internal series resistance of 250
If the calibrator shows a measurement of 0 mA,
check for reversed current leads.
If an external loop power supply is used, there
must be a resistance of between 230
Ω
connected in series with the external loop
270
supply and the transmitter.
5. The calibrator tries Poll Address 0 (single transmitter
per loop). If no connection is made, press the
softkey to scan Poll Addresses 1 through 15
(multidrop).
6. Once the calibrator establishes communication with
the transmitter, the Active Device screen appears. In
the case of a multidrop configuration, you must
choose a transmitter from a list, and press e.
Loop Power softkey to activate 24V
Note
Ω
.
Ω
and
Poll
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HART Mode Users Guide
pe06s.bmp
The Active Device screen provides the following
information for all transmitters, supported or generic:
•
Poll address (if not 0)
•
Model number and Tag ID
•
PV (Primary Variable)
•
PVAO (digital representation of the Analog Output)
•
PV LRV (PV Lower Range Value)
•
PV URV (PV Upper Range Value)
•
Softkeys for accessing HART operation menus
4
Documenting Process Calibrator HART Mode
Connecting to a HART Transmitter
V
RTD
30V
MAX
SOURCE
V
V
Hz
7
89
456
123
0
mA mA
RTD
CAT
SOURCE
MEAS
30V
30V
MAX
MAX
DOCUMENTING PROCESS CALIBRATOR
744
RTD
Transmitter
-PS
S
+PS
MEAS
SETUPmA
TC
RTD
CLEAR
(ZERO)
ENTER
.
V
300V
TC
MAX
M
-IN
+IN
Z
pe01c.eps
Figure 1. Connecting to a HART Transmitter
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HART Mode Users Guide
Supported vs. Generic Transmitters
The calibrator communicates with virtually all HART
transmitters. In addition, the calibrator is programmed to
use device-dependent commands for a selection of HART
transmitters and their software versions. These are
“supported transmitters.” All other transmitters are
“generic.”
Table 1 shows the operations that are available for
supported vs. generic transmitters in single point and
multidrop configurations.
Note
Sensor trim is provided for supported
transmitters, with a few exceptions, as identified
in the list of supported transmitters that you can
view on the display.
To display a list of supported transmitters and software
versions:
1. If the calibrator is connected to a HART transmitter
with the Active Device screen showing, press the
Abort softkey, followed by More Choices.
2. If the calibrator is not connected to a HART
transmitter, press the r key followed by
Choices
3. Press the
appears.
.
Device Revs softkey. The Browser screen
4. Press u or d to highlight the desired manufacturer,
and press e. A list of model numbers appears.
5. Press u or d to highlight the model number, and
press e. A list of software versions appears.
More
pe07s.bmp
6
Documenting Process Calibrator HART Mode
Supported vs. Generic Transmitters
Table 1. Supported vs. Generic Transmitters (Devices)
Menu Operation Supported Transmitter Generic Transmitter
Single Point Multidrop Single Point Multidrop
Top Level Active Device screen ••••
Setup Basic (read/write, cloning capability) ••••
Sensor (read only) ••••
Device Identification (read/write) ••••
HART Output (read/write) ••••
HART Information (read only) ••••
Service Loop Test • Not Available • Not Available
Pressure Zero Trim ••••
Output Trim • Not Available • Not Available
Sensor Trim ••Not Available Not Available
Process Detailed process information ••••
7
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HART Mode Users Guide
Communication Operations
Figure 2 shows the HART Mode menu tree. Availability of
some elements in the menus depends on which
transmitter you are using, and whether the transmitter is
configured by itself on a current loop or in a multidrop
connection.
Viewing Process Variables
From the Active Device screen press the Process softkey
to view more device variables and their continuously
updated values. To see additional information, press the
Next Page softkey.
pe08s.bmp
Setup Operations
The Setup softkey provides access to the following five
setup functions:
•
Basic
•
Sensor
•
Device Identification
•
HART Output
•
HART Information
Basic
From the Active Device screen press the Setup and Basic
softkeys to access the read/write Basic Setup screen. You
can use this screen to clone a transmitter as described at
the end of this manual.
pe09s.bmp
8
Documenting Process Calibrator HART Mode
Communication Operations
PROCESS
SETUP
SERVICE
ABORT
(Example)
PV
% Range
AO
SV, TV, QV
Loop test
Pressure
zero trim
Output trim
Sensor trim
• Tag
• PV units
Basic
Sensor
Device
Identification
HART
Output
HART
Information
• LRV, URV
• Damping
• Transfer function
• Software version
• Final assembly number
•Tag
• Message
• Date
• Description
• Manufacturer
• Model
• Device HART ID
• Software revision
• Hardware revision
• Number of preambles
Figure 2. 744 HART Mode Menu Tree
• Sensor serial number
• Sensor lower and
upper limits
• Sensor minimum
span
(temperature devices only)
• Sensor type
• Sensor connections
• Write protect
• Alarm state
• HART poll address
• HART burst mode
• HART burst
command
pe03f.eps
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HART Mode Users Guide
Sensor
From the Active Device screen press the Setup and
Sensor softkeys to access the read-only Sensor Setup
screen. This is where you can view information about the
sensor in the transmitter, including serial number, limits,
and span. The limits shown are the absolute limits for the
sensor. (The Upper Range Value (URV) and Lower
Range Value (LRV) are different, and are viewable and
programmable through the Basic Setup screen.)
pe10s.bmp
Device Identification
From the Active Device screen press the Setup and
Device Identification softkeys to view information about the
transmitter. You can program the Tag, Message, Date,
and Descriptor registers in the transmitter using this
screen.
pe11s.bmp
10
Documenting Process Calibrator HART Mode
Communication Operations
HART Output
From the Active Device screen press the Setup and HART
softkeys to access the read/write HART Output
Output
screen. Here you can change the Poll Address (0 = single
transmitter, any other address = multidrop), and control
burst mode.
pe12s.bmp
HART Information
From the Active Device screen press the Setup and HART
Information
Information screen. This screen shows more complete
information about the transmitter model, hardware and
software revision numbers, and how many preambles it
sends.
softkeys to access the read-only HART
pe13s.bmp
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HART Mode Users Guide
Service Operations
The Service softkey provides access to Loop Test,
Pressure Zero Trim (where applicable), Output Trim, and
Sensor Trim operations. For generic transmitters, only
Loop Test, Output Trim, and Pressure Zero Trim are
available. (See Table 1.) The trim (adjustment)
operations are described later in this manual.
Note
Loop Test and Output Trim are not available if
the transmitter is in multidrop mode.
Abort Softkey
The Abort softkey terminates the communication
operation underway, and returns control to the previous
screen. From the Active Device screen,
browser, in which you can view the list of supported
transmitters.
Abort calls up the
Interaction between Analog Mode and HART Mode
Analog mode is normal calibrator operation, as described
744 Users Manual
in the
you press the r (HART) key. This action starts
communication over the HART interface.
You can switch between HART and analog modes easily
by pressing r (or pressing M to go to analog mode
from HART mode), gaining the benefit of having the
transmitter automatically,set up analog mode for
appropriate measure and source functions, if desired.
For supported transmitters, the transition to analog mode
goes to the MEASURE/SOURCE screen, which provides
an easy way to proceed with an “as found” calibration.
For generic transmitters, the transition to analog mode
involves choosing the MEASURE or SOURCE screen,
from which you select the appropriate function.
For supported or generic transmitters, when you press
r to return to HART mode, the Active Device screen is
displayed. The HART serial communication connection
remains active as you switch between HART and analog
modes.
. HART mode is activated when
12
Documenting Process Calibrator HART Mode
Understanding HART Calibration
Understanding HART Calibration
An analog transmitter has one stage of electrical
conversion from a measured physical parameter to a
4-20 mA current loop output. A HART transmitter has the
three stages shown in Figure 3.
Depending on how the transmitter is used in your
application, you may need to test and adjust the Input
stage, the Output stage, or both. For example, if your
application requires the Primary Variable (PV) to be
correct when read by a host computer, you must calibrate
the Input stage.
If your application requires that the 4-20 mA current
output value accurately reflect what the Input stage is
measuring, you must calibrate both the Input and Output
stages.
Transmitters in multidrop systems, in which more than
one is wired in parallel, do not use their Output stages at
all. Their analog outputs are all held at an idling level of 4
mA no matter what the Input stage is measuring.
744 HART Mode Menus for Adjustment
In 744 HART mode, adjusting the Input stage is called
Sensor Trim. Adjusting the Output stage is called Output
Trim
. Both adjustments are made from the Service menu.
For pressure transmitters, there is another adjustment,
Pressure Zero Trim. This adjustment is the same as
called
trimming the lower sensor point at zero. All three
operations are run from the 744 HART mode
menu.
Service
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HART Mode Users Guide
744 Calibrator
14
Pressure zero trim
Physical
variable
Sensor trim
Input
PV PVAO
Computation
HART transmitter
Figure 3. Block Diagram of a HART Transmitter
Loop test
Output trim
Output
4-20mA
loop
pe02f.eps
Calibrating a Supported HART Transmitter
An “as found” and “as left” transmitter calibration has an
easier, more automated process for HART transmitters
than for analog transmitters. The calibration procedure is
the same as described in the
for how you set up the calibration template, and how you
adjust the transmitter.
If you are starting a calibration procedure from a
loaded Task, connect to the HART transmitter
first and establish communication before you
Task
press
The following procedure assumes that you are familiar with
using a 740 Series Documenting Process Calibrator to
calibrate analog transmitters, and are not running a loaded
Task.
1. Make the appropriate measuring, sourcing, and HART
interface connections between the calibrator and the
transmitter, and press r to establish
communication.
2. Press r to switch to analog mode.
in analog mode.
744 Users Manual
Note
, except
Documenting Process Calibrator HART Mode
Calibrating a Supported HART Transmitter
3. You are presented with a set of choices for analog
mode. Use the u and d keys to select one of the
measure/source choices. This is where you select
measure mA (analog output), or measure PV, which
does not involve the Output stage of the transmitter.
See Figure 3.
4. Press e.
5. Press the
6. Use the u and d keys followed by e to select
an instrument calibration procedure. You’ll see that
the calibration template is preloaded with appropriate
data. You can make changes to any item if you wish.
As Found softkey.
pe14s.bmp
15
744
HART Mode Users Guide
7. Proceed with calibration as usual (described in the
744 Users Manual
).
8. Press the
mode, and presents you with the Service menu for the
transmitter.
9. Do an Output Trim, a Sensor Trim, or both. These are
Service Operations, and are described later in this
manual. When you have finished with the trim
procedures, press the
10. Press the
procedure to verify that the transmitter passes.
Adjust softkey. This returns you to HART
Done softkey.
As Left softkey and repeat the calibration
Loop Test
The Loop Test feature sends a command to the transmitter
to set its output stage to a specified value. Use this to
check the calibration of the output stage, or to check for
proper reading on an external loop reading device.
To perform a Loop Test:
1. From the Active Device screen Press the
softkey, followed by Loop Test.
Service
2. Press a softkey to command the transmitter to set its
analog output to the corresponding value, or manually
enter a value with the numeric keys.
In the middle of the screen the transmitter acknowledges
the selected PVAO (digital representation of the Output
stage). The calibrator shows the measured value at the top
of the screen, so you can use Loop Test as a quick way to
check the calibration of the transmitter’s Output stage.
pe15s.bmp
16
Documenting Process Calibrator HART Mode
Calibrating a Supported HART Transmitter
Output Trim
An Output Trim adjusts the tranmitter’s Output stage. You
can perform an Output Trim on both generic and
supported transmitters.
To perform an Output Trim:
1. From the Active Device screen Press the
softkey, followed by Output Trim.
2. Press Fetch to load the mA value being measured by
the calibrator into the dialog box.
3. Press
4. To trim the high analog output point, repeat steps 2
Send to trim the low analog output point.
and 3, following the prompts on the display.
Service
pe16s.bmp
Sensor Trim
You can only perform a Sensor Trim on a supported
transmitter. A Sensor Trim adjusts the Input stage of a
HART transmitter. If your application does not use the
Output stage of the transmitter, Sensor Trim is the only
adjustment you need to make.
A Sensor Trim may involve one or more trim points. This is
controlled by the transmitter’s software. You can only
perform a Sensor Trim on a supported transmitter.
To perform a Sensor Trim, proceed as follows:
1. From the Active Device screen, press the
softkey, followed by Sensor Trim.
Service
pe17s.bmp
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744
HART Mode Users Guide
2. Use the u and d keys to select the Sensor Trim
operation, and press e.
3. Follow the instructions on the display. For pressure,
there is a message to connect a pressure module to
the calibrator, and another to press the c key to
zero the pressure module.
4. Press
Continue.
pe18s.bmp
5. Enter the trim value you want the calibrator to
produce, and press e, or in the case of a
pressure transmitter (as above), press
the value being measured by the Fluke pressure
module into the dialog box.
6. Press
7. If prompted to do so, repeat steps 2 and 3, following
Trim.
the prompts on the display, to trim the remaining
points.
Fetch to load
Note
Select trim points near the range limits unless the
transmitter’s documentation specifies otherwise.
If you get an error message that for the selected
trim point there is an excess correction,
sometimes you can solve the problem by doing a
series of Sensor Trims in small steps from the
previous trim point toward the desired trim point.
18
Documenting Process Calibrator HART Mode
Cloning a Transmitter
Cloning a Transmitter
Cloning copies the Basic Setup information from one
transmitter to another. You can clone generic and
supported transmitters.
To use the calibrator to clone a transmitter:
1. Connect the calibrator to the transmitter you want to
clone. You only need a communication connection.
2. From the Active Device screen, press the
softkey.
3. Use the u or d keys to select
the screen and press e.
Basic from the list on
Setup
pe09s.bmp
4. Press the Store Page softkey to load the settings into
the calibrator’s memory (not the transmitter).
5. Disconnect the calibrator from the transmitter and
connect it to the transmitter you want to configure.
Press the
6. Press the
the Basic Setup screen.
7. Press the
display with the cloned parameter settings. The
settings are not transmitted to the transmitter at this
time.
8. Use the u or d and ekeys to select
parameters one at a time, change them, or leave them
as cloned, and press the
them to the transmitter.
Abort softkey to establish communication.
Setup softkey, then select Basic to return to
Recall Page softkey to refresh the calibrator
Send softkey to transmit
19
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HART Mode Users Guide
20
Index
—A—
abort, 12
active device screen, 4
analog mode, 12
as found, 15
as left, 15
—B—
basic setup, 8
browser screen, 6
—C—
calibrating a HART transmitter, 15
cloning, 19
communication test leads, 3
—D—
device identification, 10
—E—
external series resistor, 3
—G—
generic transmitters, 6
—H—
HART information, 11
HART mode, 12
HART output, 11
—I—
input
stage, 13
—L—
loop power, 3
loop test, 16
LRV, 4
—M—
model numbers, 6
multidrop, 8, 13
21
744
HART Mode Users Guide
—O—
output
stage, 13
output stage, 16
output trim, 13, 17
—P—
phone numbers for Fluke, 2
pressure module, 18
pressure zero trim, 13
process variables, 8
PV, 4
PVAO, 4, 16
—R—
recall page, 19
—S—
sensor, 10
sensor trim, 13, 17
serial communication, 3
series resistor, 3
service operations, 12
setup
basic, 8
device identification, 10
HART information, 11
HART output, 11
sensor, 10
software versions, 6
store page, 19
supported transmitters, 6
—T—
task, 744, 15
telephone numbers for Fluke, 2
trim
output, 13, 17
pressure zero, 13
sensor, 13, 17
—U—
URV, 4
22
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