The Principle of electronic thermal mass flow switch based on the principle of thermal theory, there are two resistances in the closed probe . One resistance was heated and regarded as detected resistance , the other one was heated and regarded as standard resistance . When the medium is flowing ,the heat on the heated resistance will be taken away and the resistances#39; value will be changed . The differential resistances value is the basis of determining the flow velocity .

Long probe large pipeline dedicated electronic flow switch NK300

Applications ：

gaseous /liquid
Control of cooling lubricant systems

Monitoring of cooling circuits

Control of filter units

Dry run protection in pumps
The flow switch for ground-source heat-pump is mainly applicable to industrial automation/mechanical equipment/air compressing industry/ refrigeration and air-conditioner. The magnet not contact with flowing water, so can normally work in sewage discharging system.

Special features：

Reliable flow monitoring of liquid media

Switching and analogue outputs for flow, temperature and diagnostics

Easily parameterisable via the local display

Free from wear, without any moving parts in the medium

Technical Parameters

*Set the range： 1...150cm/s(water），3...300cm/s(oil），20...2000cm/s(air）

*Signal output： PNP,NPN，relay，Normally open + normally closed（SPDT）

*The power supply： 24V±20%VDC or 230V±15%VAC

*Current is switched on：Maximum 400mA(PNP or NPN), maximum 4A (relay)*

*No-load current： Maximum 80mA

*Flow indicator： LED row (6)

*Set way： Potentiometer setting

*Pressure range： 100bar

*The temperature gradient：≤4°C/s

*The response time： 1-13s,Typical values 2s

*Initialization time： 8s

*Electric protection：Invert, short circuit

Overload protection

*Protection grade： IP67

*Medium temperature：-20...80°C

*The environment temperature：-20...80°C

*Storage temperature： -20...100°C

*Connection mode：M12 plug-in/direct attachment line

*Material：

           probe： Stainless steel

           shell： PBT

           weight： 0.4kg