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Figure Connecting to a HART Transmitter... 5 744 HART Mode Menu Tree... 9 Block Diagram of a HART Transmitter ... 14 List of Figures Title Page...
Introduction Warning To avoid electric shock, read the Safety Information in the 744 Users Manual before you use the Fluke 744 Documenting Process Calibrator. With analog transmitters, you must make a hardware adjustment during calibration. With HART (Highway- Addressable Remote Transducer) transmitters, adjustments are by remote command.
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: +65- -276-6196 Anywhere in the world: +1-425-356-5500 Or visit us on the World Wide Web: www.fluke.com...
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 terminals on the transmitter, press r , and you are done.
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HART Mode Users Guide 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 pe06s.bmp...
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Documenting Process Calibrator HART Mode Connecting to a HART Transmitter DOCUMENTING PROCESS CALIBRATOR Transmitter ( ZERO) pe01c.eps Figure 1. Connecting to a HART Transmitter...
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.”...
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Table 1. Supported vs. Generic Transmitters (Devices) Menu Operation 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 Pressure Zero Trim Output Trim Sensor Trim Process Detailed process information...
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.
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(Example) % Range PROCESS SV, TV, QV SETUP Loop test Pressure zero trim SERVICE Output trim Sensor trim ABORT Documenting Process Calibrator HART Mode • • PV units • LRV, URV Basic • Damping • Transfer function Sensor • Software version •...
HART Mode Users Guide Sensor From the Active Device screen press the softkeys to access the read-only Sensor Setup Sensor 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.
HART Output From the Active Device screen press the 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. Documenting Process Calibrator HART Mode HART Information From the Active Device screen press the Setup...
HART Mode Users Guide Service Operations softkey provides access to Loop Test, Service 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.
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.
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HART Mode Users Guide Sensor trim Pressure zero trim Input Physical variable 744 Calibrator PVAO Computation HART transmitter Figure 3. Block Diagram of a HART Transmitter Loop test Output trim 4-20mA Output 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 744 Users Manual , except for how you set up the calibration template, and how you adjust the transmitter.
HART Mode Users Guide Proceed with calibration as usual (described in the 744 Users Manual ). Press the softkey. This returns you to HART Adjust mode, and presents you with the Service menu for the transmitter. Do an Output Trim, a Sensor Trim, or both. These are Service Operations, and are described later in this manual.
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: From the Active Device screen Press the softkey, followed by Output Trim Press to load the mA value being measured by Fetch the calibrator into the dialog box.
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Continue 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. Press Trim...
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: Connect the calibrator to the transmitter you want to clone. You only need a communication connection. From the Active Device screen, press the softkey.