The ISNV air velocity and direction meter is designed for continuous technological measurement of air velocity and control of the direction of air movement, as well as for indirect automatic measurement of the volumetric air flow rate in mine workings, including those hazardous for gas or dust, in temperate, cold and tropical climates. (ambient temperature from minus 5 to plus 35 ° С, relative humidity up to 100%, dust content 1 g / m3). The ISNV meter consists of a dispatching semi-set of DP, a tachometer PT converter and a portable PI indicator.