air flow rate

airflow rate Mechanical switch contact Versatile fields of application Small size Easy to connect

The airflow monitor (NC / NO) is designed to indicate the loss of air movement of a fan or filter fan. The contact detects the loss of air movement caused by fan failure or blocked filter media regardless of direction of air. Its simple mechanical operation makes it a viable alternative to electronic monitoring system. 

Technical Data:

Contact type	reed / magnet contact
Normally closed (NC)	switch contact open when air is flowing
Normally open (NO)	switch contact closed when air is flowing
Max. switching voltage	NC: 240VDC (UL), 240V AC/DC (VDE) / NO: 60VDC
Max. switching current	NC: DC 500mA / NO: DC 170mA
Max. switching capacity	10W (resistive load)
Switching threshold of airflow velocity	> 2.5m/s (hysteresis: > 1m/s)
Max. airflow velocity	50m/s
Contact resistance	< 370mOhm (with wire)
Max. air humidity	70% RH (not precipitating)
Service life	> 100 000 cycles
Connection	2 x single strand AWG 28, length 500mm, tip of stranded wire 5mm stripped and tinned (NC: black, NO: blue)
Mounting	alternatively integrated in protective grille (see table), mounting clamp or mounting clip
Casing	plastic according to UL94-HB, black
Fitting position	bidirectional tab perpendicular to airflow
Operating/Storage temperature	-20 to +50°C (-4 to +122°F) / -20 to +80°C (-4 to +176°F)
Protection type	IP20
Approvals	VDE + UL File No. E250507
Note	The product of switching voltage and switching current must not exceed 10W. The max. voltage and max. current must not be exceeded, not even short-term (voltage/current peaks). The resulting voltage and current peaks of inductive or capacitive loads must be restricted by a contact protection circuit.

Technical Data:

Contact type	reed / magnet contact
Normally closed (NC)	switch contact open when air is flowing
Normally open (NO)	switch contact closed when air is flowing
Max. switching voltage	NC: 240VDC (UL), 240V AC/DC (VDE) / NO: 60VDC
Max. switching current	NC: DC 500mA / NO: DC 170mA
Max. switching capacity	10W (resistive load)
Switching threshold of airflow velocity	> 2.5m/s (hysteresis: > 1m/s)
Max. airflow velocity	50m/s
Contact resistance	< 370mOhm (with wire)
Max. air humidity	70% RH (not precipitating)
Service life	> 100 000 cycles
Connection	2 x single strand AWG 28, length 500mm, tip of stranded wire 5mm stripped and tinned (NC: black, NO: blue)
Mounting	alternatively integrated in protective grille (see table), mounting clamp or mounting clip
Casing	plastic according to UL94-HB, black
Fitting position	bidirectional tab perpendicular to airflow
Operating/Storage temperature	-20 to +50°C (-4 to +122°F) / -20 to +80°C (-4 to +176°F)
Protection type	IP20
Approvals	VDE + UL File No. E250507
Note	The product of switching voltage and switching current must not exceed 10W. The max. voltage and max. current must not be exceeded, not even short-term (voltage/current peaks). The resulting voltage and current peaks of inductive or capacitive loads must be restricted by a contact protection circuit.