Flow direction switch VA 409 with direction indication serves to determine the flow direction of compressed air and gases especially in closed ring main applications. Flow sensor VA 409 is able to detect even the smallest changes in the flow direction quickly. Using the VA 409 with flow direction indication, the flow direction of the compressed air can be determined quickly and easily.
The direction information in form of a potential-free contact (normally closed max. 60 VDC, 0.5 A) is transferred to the
flow sensors VA 400/VA 420 or to a separate building management system (mbs). Two LEDs show the flow direction. In conjunction with 2 flow sensors, either VA 400/VA 420 incoming and outflowing compressed air in closed circular pipelines can be measured precisely.
- Detects smallest changes
- < 0.1 m/s referred to 20 °C and 1000 mbar
- No mechanical wear parts
- Easy installation under pressure