How to Perform a Pressure Calibration Using the Fluke 729


In this video, you will learn how to calibrate a pressure transmitter using the Fluke 729 Automatic Pressure Calibrator.


The first step in the process is connecting your calibrator to the transmitter using the 4-20 mA jacks. Going to the plus and minus on the transmitter, then connect your pressure hose from the 729 to the pressure ports of the transmitter.

On the 729, you'll see the units are on KPA, but we want to adjust that to PSI. Do this by using the arrow keys to highlight KPA, press enter, and then switch that to PSI. Next, we're going to vent the 729 and zero the pressure. Then, to continue setting up, we're going to select the type of transmitter. In this case it's pressure and current out, so we'll select number one on the screen.

We're going to select the lower and upper range pressure for the calibration. This transmitter is 0-100 PSI, so we're going to move the cursor down two, the 100% and change this to 100 PSI. 4-20 mA, press F4 to continue, and then also press Loop Power to power up. The tolerance range defaults to .2% and we can leave that there.

Use the arrow keys to navigate to the different menus on the tool. You can see different areas of the 729, for example, test strategy. For this example, we are going to select three up. Auto-settling time, we'll leave at five seconds. And the transfer function, you can have set for linear or square root; we'll leave that at linear. Press F four. Now select auto test.

Perform a pressure calibration

The Fluke 729 is going to go to each set point with the pump, and then it gets close, the automatic regulator will bring the pressure to the exact 50 PSI setting for this particular test spot. It will then settle for five seconds, taking the 4-20 mA reading.

Documenting your calibration

This calibration did pass; it's in the percentage of error. Press done here to document the report. Tag ID allows you to enter in the value, in this case it's PT100. If you move down to serial number, you can now enter the serial number of the device. And then for user ID, you can select user list or put a name in. In this case we can go to user list F1 and select the name of the technician.

Once you've completed adding information, press done and now the calibration has been documented. If it was out of spec, you could go to make adjustments, and then do an as-left. In this case, it is in specification, so you can press F4 and you've completed a process calibration.