For indication of process parameters and identification of measurand tendency (trend monitoring) for the most part analog indicators in form of circular professional scales direct-reading instruments or bar graph professional displays are used.

Analog indicators contain motor-driven potentiometric as measuring system that can be designed as bridge or balancing circuit accepting resistance, current or voltage inputs.

Such systems provide the design of any scale angle, exceeding the full range of 360° shaft rotation as wel,l e.g. for indicating wind direction or the position of a variable-pitch propeller on ships.