So how exactly does a calorimetric flow switch work?

If the presence of flow in a piping system should be monitored, a calorimetric flow switch ? often known as a flow monitor ? is often used. But so how exactly does a calorimetric flow switch actually work? The following blog post explains this in greater detail.
Calorimetric flow switches, which are generally also referred to as thermal flow monitors, use the physical laws of heat transport in flows. A distinction is actually made between two technical solutions: continuous and regulated heating.
What No One Tells You of a measuring probe for a calorimetric flow switch
Continuous heating
A flow switch that is in line with the calorimetric measuring principle consists of a measuring probe with two temperature sensors integrated into it (see illustration). One of the sensors is heated continuously with the aid of a heating element (wire-wound) with a continuing heating power and measures the temperature at the heating element. Have You Heard determines the temperature of the medium in the pipe. Consequently, a temperature difference occurs between your two sensors, which is registered by the electronics. The bigger the flow velocity of the medium in the pipeline, small this temperature difference is. The basis for this may be the cooling aftereffect of flowing media. The molecules in the medium, which are flowing at night probe tip, collect ?packages of heat? and transport them away. The more molecules flow past, the greater the cooling effect. The amount of molecules passing by increases continuously with increasing flow velocity.
Regulated heating
The measuring probe is basically identical in design: You can find two temperature sensors in the medium, one of and this can be heated. In this technical solution, the heating power is regulated so that the temperature difference between your two temperature sensors is kept constant throughout. Consequently, as the flow velocity increases, the heating power should be increased in order to keep how big is the temperature difference constant. The applied heating power is thus a direct measure of the flow velocity in the medium.
Note
Do you have further questions on the measuring principle behind the calorimetric flow switch or do you want help with the selection of this type of product? In its portfolio, WIKA includes a calorimetric flow switch for monitoring the flow of liquid media (model FSD-3). Your contact person will undoubtedly be happy to assist you to.

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