Fluke 744 manual Connecting to a Hart Transmitter

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Documenting Process Calibrator HART Mode Connecting to a HART Transmitter
4. If the transmitter is not powered by a loop power supply, press the Loop Power softkey to activate 24V loop power.
Note
The calibrator provides loop power through an internal series resistance of 250 Ω.
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 and
270 Ω connected in series with the external loop supply and the transmitter.
5. The calibrator tries Poll Address 0 (single transmitter per loop). If no connection is made, press the Poll 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.
3

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.

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 rkey.

Note

The square-root symbol on rkey is there only for calculator mode. At all other times, there is no square-root function associated with the

rkey.

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Contents 744 Page Table of Contents 744 Hart Mode Users GuideList of Tables 744 List of Figures 744 Introduction Documenting Process Calibrator Hart ModeHow to Contact Fluke Connecting to a Hart Transmitter ∙ Poll address if not Documenting Process Calibrator Hart Mode Supported vs. Generic Transmitters Supported vs. Generic Transmitters Viewing Process Variables Setup OperationsCommunication Operations Hart Mode Menu Tree Sensor Hart Output Hart Information Abort Softkey Interaction between Analog Mode and Hart ModeService Operations Understanding Hart Calibration Hart Mode Menus for AdjustmentBlock Diagram of a Hart Transmitter Calibrating a Supported Hart Transmitter Loop Test Sensor Trim Output TrimPress Continue Cloning a Transmitter 744 Index Device identification