VA 409 – Flow Direction Switch for Compressed Air Systems

The new thermal flow direction switch, VA 409 with direction indication, is designed to determine the flow direction of compressed air and gases, especially in closed circular pipelines.

The VA 409 quickly and safely establishes the flow direction of compressed air. Unlike its mechanical paddle flow switch predecessors, the VA 409 can detect even the smallest changes in flow direction swiftly and without any mechanical movement.

Direction information is relayed as a potential-free contact (normally closed max. 60 VDC, 0.5 A) to the consumption sensors VA 500/ VA 520 or to a separate building management system (mbs). Two LEDs indicate the flow direction.

Used in conjunction with two consumption sensors VA 500/ VA 520, the incoming and outgoing compressed air in closed circular pipelines can be measured with precision.

TECHNICAL DATA VA 409

Response area detection of direction:	< 0.1 m/s relative to 20 °C and 1000 mbar
Measuring principle:	Calorimetric measurement
Sensor:	Pt 30/ Pt 700/ Pt 330
Measured medium:	Air, gases
Operating temperature:	0…50 °C sensor tube -20…70 °C housing
Operating pressure:	up to 16 bar
Power supply:	24 VDC, 40 mA
Current consumption:	Max. 80 mA to 24 VDC
Protection class:	IP 54
EMC:	in acc. with DIN EN 61326
Connection:	2 x M12, 5-pin, plug A and plug B
2 potential-free contacts:	2 x U max. 60 VDC, l max 0.5 A (normally closed); On request: Normally open
Housing:	Polycarbonate
Sensor tube:	Stainless steel, 1.4301, length 160 mm, Ø 10 mm, safety ring Ø 11.5 mm, longer sensors on request
Mounting thread:	G 1/2″
Housing diameter:	65 mm
Direction indication:	2 LED`S