The units for each axis can be changed by selecting Units > from the View menu, and then selecting the axis for which you would like to change the units. The most widely used units are predefined in the program. The user can also choose custom units by manually entering the conversion factors. This is most useful for the L420 logger where the 4 – 20 ma loop usually corresponds to a physical measurement. The window below shows typical entries for a 4 – 20ma PH sensor.