Calorimetric Flow Meter / Monitor / Totaliser DVK
Measuring range: 1 - 10 ... 50 - 500 l/min air
Connection: G ¼ ... G ½
Material: connection: stainless steel, housing: PPS
pmax: 10 bar
tmax: 50 °C
Accuracy: ±5 % of full scale
LED-indication, 2 open collector PNP, totalizing function
The digital KOBOLD flow meter/monitor model DVK serves to measure and monitor small and average flows of air in piping and hoses. The device is absolutely maintenance-free and uses the calorimetric method. When the operating voltage is applied, a thermistor integrated in the sensor is heated to a defined value above the medium temperature. When air (or gas) flows through the sensor, the heat generated in the sensor is absorbed by the medium.
This means that the sensor is cooled down to the medium temperature. Depending on the velocity and rate of flow, the temperatures are equalized and the resistance of the sensor is reduced proportionally. The flow velocity can be determined by measuring the resistance. The medium temperature is measured by a second sensor. The resistance values of both sensors are compared by the electronics over a Wheatstone bridge circuit and an output relay is actuated if the set switching values have not been made or exceeded.
The switch state is signalled by two LEDs (ON: LED on; OUT 1*: green, OUT 2*: red). The digital KOBOLD flow meter type DVK works with practically no pressure loss. Typically, the device is available in two different versions (display and sensor as compact instrument, or display and sensor separated but connected with a cable) with the necessary screw connections.