How to calibrate a HART Pressure Transmitter from a downloaded task with the Fluke 729


This video will show you how the Fluke 729 Automatic Pressure Calibrator performs a HART Calibration from a downloaded task.


This unit already has a downloaded task from our software which DPCTrack2 or ProCalV5 can be used. The first thing you want to do is connect up, so you've got the 729 with the 4-20 mA jacks connected up to the transmitter as well as the pressure line from the calibrator to the transmitter.

Setting up your HART calibration

Next thing you want to do is you want to vent this thing out, zero your pressure. And then let's go ahead and press HART to get things going. Once you press HART, you need to enable your 250 ohm resistor and enable loop power. The transmitter is now seen by the 729.

Press continue. The 729 is going to go ahead and look at all the Information about that device and now we're connected and ready to calibrate.

Let's go ahead and find that downloaded task that we just sent down to the calibrated from DPCTrack2. I'll just scroll down on the 729, find task by tag, and there it is. So, you see it's a PT100 and there's a serial number. If it matches up, it'll show up on the screen and is ready to go so we can press F4 to recall it. Notice the Fluke 729 already has the HART information about the device; it knows it's a pressure and current out, 0 100 PSI range. Press continue. It Automatically has set the tolerance in this case at .5. Test strategy was set to be a 3 up test with an auto settling time of 3 seconds between test points, and the transfer function is set for linear, not square root.

Screen settings

  • Tolerance of range: 0.50%
  • Test strategy: 3 up
  • Auto setting time: 3 seconds
  • Transfer function: Linear

Transfer function: Linear

Running your HART calibration auto test

Go ahead and press F4 to begin the auto test and the 729 is going to go to work. This is a 3 up test, so the Fluke 729 is going to take readings at 0, 50, and 100. Watch the screen as it gets close to the set point, you'll notice the pressure will stop and then the automatic regulator will kick in and fine tune to the exact set point. It will then hold on to it for the 3 second delay we put in and then take the 4-20 mA reading before moving on to the final test point.

Once that final reading has been made, then you'll get the results shown on the screen here. In this case it passed calibration, so we've completed the documenting, press F4 for done. Notice the tag ID and the serial number are already included on the screen. It knows that from the task and verified by the HART communication. We can go to the user list and select the user who did the task. Press F4 for done.

If it was out of spec we could go ahead and do HART adjust to the 4-20 mA trim as well as, if necessary, trim to apply values for the sensor. Once you complete that, go ahead and do your as-left to complete your as-found and as-left test results.

Press done and we have completed our calibration.

After a completed calibration

Once you have completed your calibration you can go ahead and review the results in memory. If you go to “Set Up” and then you can scroll down to “Manage Test Results,” press ENTER and you can see the task, the test results, that we've just completed on that PT100 transmitter. If you press ENTER here, you can look at the actual test results to verify before you then upload that test result to software such as DPCTrack 2 or ProCalV5.