This article applies to all Ralston Field Gauge LC20 and Process Meter LC30 models.
Press and Hold the Menu/Up Arrow Button.
Press the Backlight/Right Arrow Button to scroll to UNITS
Press the Zero/Check Mark Button to enter the Units submenu.
The checkmark indicates current the current units the Field Gauge/Process Meter is set to display.
If you do not wish to change engineering units, press the Menu/Up Arrow Button twice to return to the main pressure screen.