Calibrate the pressure sensor on a Field Gauge and Process Meter

Calibrate the pressure sensor on a Field Gauge and Process Meter

Do-it-yourself instructions for calibrating a Ralston digital gauge with the free FieldLab Desktop software. At the end of this process, FieldLab Desktop will automatically make any necessary adjustments to bring your Ralston gauge to acceptable tolerances.

This article applies to the following devices:
  1. Process Meter LC20, all models.
  2. Field Gauge LC 10 and LC20, all models equipped with one or more pressure sensors.

Things you will need:
  1. A PC running Windows.
  2. FieldLab Desktop software version 1.38.0 (or later) installed on your PC. Download the latest version for free.
  3. A Ralston Instruments digital gauge.
  4. USB Cord, provided with your Ralston gauge.
  5. A pressure source that can generate enough pressure to take the Ralston gauge to full span.
  6. A reference pressure gauge with the following:
    1. Reference gauge should be 4 times more accurate than the Ralston gauge you are calibrating.
    2. Reference gauge must have a full span equal to or greater than the full span of the Ralston gauge.

1. Connect the Ralston gauge and reference gauge to the same pressure source.

2. Power on the Ralston gauge.

3. Connect Ralston gauge with the provided USB cord to a PC running FieldLab Desktop.

4. In FieldLab Desktop on your PC, select the Ralston gauge you want to calibrate from the Devices screen.

5. On the gauge Overview screen, select the tab titled "Sensors".

Select the tab titled Sensors


6. On the Sensors screen, select the button titled "Calibration".



7. Select the pressure engineering units you want to use for the calibration process.




Note: The example screens in this support article were taken from a Ralston gauge model with a full span of 300 psi.
Ralston gauges are available with full spans from 30 to 10,000 psi; so when you are calibrating your Ralston gauge be sure to follow the actual Min, Mid, and Max calibration points displayed on your computer screen in FieldLab desktop.

8. Adjust the pressure source to the target pressure.
FieldLab Desktop display the live pressure reading from the Ralston gauge via the USB connection. FieldLab Desktop cannot see the reading on the reference device, so you will need to adjust the pressure so that the reference device displays each target pressure.

If you can't get the reference device to read exactly the target pressure get it as close as you can and then manually enter the reference device reading into the Reference Reading field using your keyboard.

9. When the reading on the reference device indicates you have reached the target pressure, select the "Log Reading" button.




10. Select the button titled “Up Next, Mid Point” to proceed to the next reference point.



Repeat steps 8, 9, and 10 above for each of the remaining reference points.

11. Once you have logged the Min, Mid, and Max Points, select the Make Adjustments button.
After you select the Make Adjustments button, FieldLab Desktop will recalibrate the Ralston gauge if it is out of spec.

Select the Make Adjustments button once you have logged the Min, Mid, and Max points.


12. Set the Next Calibration Date


13. Save Changes so that the next calibration date will be recorded on your Ralston gauge and in FieldLab Desktop.

14. Select Exit to return to the overview screen for your Ralston gauge.


    • Recent Articles

    • Getting Started: Run Your First Test with FieldLab Mobile

      This guide walks you through connecting a gauge, logging data, and retrieving a completed test run. This walkthrough uses a single gauge, but FieldLab Mobile supports multiple gauges and readings in a single test. The following guide applies to ...

    • Update custom unit edits on your Field Gauge and Process Meter

      Applies to FieldLab Desktop app versions 2.0 and later Learn how to: Create a custom pressure unit in FieldLab Desktop When you edit and save an existing custom unit, it will need to be manually updated on any Field Gauge or Process Meter that had ...

    • Update edits to custom fields on your FieldLab

      Applies to FieldLab Desktop versions 2.0 and later When you edit and save an existing custom field name, the edit will automatically update in all Test Modes saved in the Test Library. Any Test Modes that use the edited custom field and are installed ...

    • Update edits to custom pressure units on your FieldLab

      Applies to FieldLab Desktop versions 2.0 and later If you have edited and saved an existing custom pressure unit and it is already being used in a Test Mode installed on your FieldLab, you will need to delete and re-add the Test Mode on the FieldLab ...

    • Remove zero offsets on a gauge with FieldLab Desktop

      This article applies to all Ralston gauges that have a pressure sensor installed. The remove zero offset feature is available in FieldLab Desktop versions 2.0 and later. If you have the FieldLab Desktop App installed on your computer, update to the ...