Fluke 709H Precision mA HART Loop Calibrator

The Fluke 709H is a professional loop calibrator designed for technicians who need more than basic 4–20 mA measurement. It combines precision current sourcing and measurement with HART communication, diagnostics and calibration functions in a compact field instrument.

Its combination of 0.01% accuracy, HART communication, 24 V loop power and data logging makes it particularly suitable for commissioning, calibration and troubleshooting of smart process transmitters.

Precision 4–20 mA Loop Calibration

The Fluke 709H supports mA source, simulation, measurement and mA measurement with loop power. Its mA range is 0 to 24 mA, allowing technicians to test standard 4–20 mA process signals as well as signals outside the normal operating range.

Key performance:

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  mA range: 0 to 24 mA
  
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  Voltage measurement: 0 to 30 V DC
  
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  mA resolution: 1 µA
  
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  Voltage resolution: 1 mV
  
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  Accuracy: 0.01% ± 2 counts
  
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  Loop compliance voltage: 24 V DC at 20 mA
  
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  Operating temperature: -10 to +55 °C
  

Integrated HART Communication and Diagnostics

The major advantage of the Fluke 709H HART Loop Calibrator is its integrated HART functionality.

In communicator mode, the instrument can read basic device information, perform diagnostic tests and trim calibration on many HART-enabled transmitters. This can reduce the need for a separate HART communicator, laptop and external HART modem for routine field work.

The built-in selectable 250 Ω resistor also simplifies HART communication when testing compatible loops.

Data Logging for Troubleshooting

The 709H can record transmitter and process information for troubleshooting and documentation.

Its data logging function provides:

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  Selectable recording intervals from 1 to 60 seconds
  
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  Up to 9,800 records
  
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  Up to 99 individual sessions
  
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  Measurement data plus the four process variables and standard status information
  

With the optional 709H/Track software and cable, calibration data can also be transferred for documentation in CSV or TXT format.

Fast Field Operation

The Fluke 709H uses a Quick-Set rotary encoder to simplify setup and adjustment during field calibration.

The large backlit display is designed for visibility in dark or confined working areas, while the compact protective holster makes the instrument practical for portable instrumentation maintenance.

Loop Power and Transmitter Testing

The 709H provides 24 V DC loop power at 20 mA, allowing technicians to power compatible current loops during testing.

The instrument requires only a simple two-wire connection for its measurement functions, helping simplify field troubleshooting and commissioning.

Adjustable Signal Testing

The Fluke 709H supports adjustable 0–20 mA or 4–20 mA spans, as well as variable step and ramp functions.

Its valve test functionality can also simulate defined mA values using percentage keys, making it useful for checking the response of current-controlled process loops.

Rugged Portable Design

The Fluke 709H is designed as a handheld field instrument rather than a bench calibrator.

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  Compact dimensions: approximately 150 × 90 × 30 mm
  
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  Weight: approximately 0.3 kg
  
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  Power: 6 × AAA alkaline batteries
  
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  Typical battery life: 40 hours
  
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  Backlit graphical LCD
  
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  Auto shutdown function
  
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  Over-voltage protection up to 240 V AC
  
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  Three-year warranty
  

Typical Applications

The Fluke 709H is suitable for:

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  HART transmitter calibration
  
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  4–20 mA loop testing
  
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  Pressure transmitter testing
  
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  Temperature transmitter testing
  
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  Flow transmitter testing
  
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  Level transmitter commissioning
  
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  Smart instrument troubleshooting
  
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  Process loop commissioning
  
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  HART device diagnostics
  
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  Field calibration documentation
  
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  PLC/DCS analog input verification
  

Fluke 709H vs. Fluke 709

The two models share the core precision mA loop calibration functions, including 0.01% accuracy, 0–24 mA range, 1 µA resolution and 24 V loop power. The major difference is that the 709H adds HART communication, diagnostics and advanced data logging/documentation capabilities.

For applications that require direct interaction with HART-enabled transmitters rather than only mA signal calibration, the 709H is the more capable choice.

FAQ

What is the Fluke 709H used for?

The Fluke 709H is used for precision 4–20 mA loop calibration, HART communication, transmitter troubleshooting and process instrumentation maintenance.

Does the Fluke 709H support HART?

Yes. HART communication and diagnostics are integrated into the 709H, and the instrument includes a selectable 250 Ω resistor for HART communication.

What is the accuracy of the Fluke 709H?

The specified accuracy is 0.01% ± 2 counts across its measurement ranges under the stated reference conditions.

Can the Fluke 709H source and simulate 4–20 mA?

Yes. The 709H supports mA source, mA simulate, mA read and mA read/loop power functions, with a 0–24 mA range.

Can the Fluke 709H power a transmitter?

The instrument provides 24 V DC loop power at 20 mA, allowing it to power compatible current loops during testing.

Does the Fluke 709H include calibration documentation?

The standard package includes a NIST-traceable calibration report and data. Optional 709H/Track software and cable can transfer calibration data in CSV or TXT format.