Arrow and scale indicators

Digital indicators are inconvenient when quickly assessing the values ​​of parameters and their rate of change, which justifies the use of dial gauges in tracking mode, when setting and adjusting.

Scales are round, horizontal or vertical linear. In most cases, for setting and tracking, it is preferable to move the arrow while the scale is fixed. Open window scales located behind the instrument panel are preferred for a wide range of measurements, fast reading of accurate values, but such scales complicate the design of the front panel. Movable scales with a fixed arrow (point of reference) are obtained when applying tick marks on the drive elements of an op amp, limbs of adjustment.

For confident and fast recognition of the indicator-risks, the distance between them and the inscriptions are relatively large, so that when the distance to the operator’s eye is about 1 m, ensure sufficient (at least 20 ') angle of view between adjacent risks.

When the workplace is not sufficiently illuminated, for example, when working with a CRT, the backlight of the scales is used with the help of instrument incandescent bulbs, realizing it with direct or reflected light. When organizing illumination, the operator's eyes must be protected from direct light.

Electromechanical dial gauges for digital information processing, typical for modern RES, require the introduction of additional digital-analog converters. These contradictions are eliminated in electronic discrete-analogue scale indicators, which in fact represent the sign-synthesizing indicators, in which the segments are drawn out in the form of linear scale scratches. Combined indicators combine the advantages of digital and analog ways of presenting information.