Ahlborn ALMEMO 2390-5 Manuel de service

3Selecting the Right Flow Sensor 3.5 Flow Sensors3.5.1 Selecting the Right Flow Sensor For measurement of flow velocities the ALMEMO® sensor range

ThermoanemometerZero Point Correction: Generally, a re-adjustment of the zero point is not required. However, during long term operation or when expo

3Thermoanemometer Technical Data:Electronics Box with SensorMeasuring range: FV A605 TA1(O): 0.01 to 1m/sFV A605 TA5(O): 0.15 to 5m/sResolution: FV

ThermoanemometerThermoanemometer MT 84x5The thermoanemometers MT 84x5 are laser-calibrated, high-precision probes with adjustable measuring ranges an

3Thermoanemometer Technical Data MT 84x5:Measuring ranges: MT 8455, MT 8465 adjustable from 0.125 m/s to 1.0 / 1.25 / 1.5 / 2.0 / 2.5 / 3.0 / 4.0 /

Pressure Modules for Dynamic Pressure3.5.3 Pressure Modules for Dynamic PressureBasic PrinciplesThe air velocity is determined by the dynam-ic pressu

3Pressure Modules for Dynamic Pressure Air velocity for selected dynamic pressures (Prandtl Pitot tube, T = 22 °C)Dynamic pressure [Pa] Dyn. press

Pressure Modules for Dynamic PressureExample: Air velocity 50 m/s, air temperature 80 °C, atmospheric pressure 960 mbar. The measured value must be m

3Pressure Modules for Dynamic Pressure Zero Point Correction of the Pressure SensorsThe zero point of the pressure sensors can shift due to positio

Pressure Modules for Dynamic PressureTechnical DataPressure connector:Overload capacity: maximum triple measuring rangeMax. common mode pressure: 700

3Rotating Vanes 3.5.4 Rotating VanesFor flow measurements the ALMEMO® sensor range provides the rotating vanes FV A915-Sxxx wit

Selecting the Right Flow Sensor Sensor: Advantages DisadvantagesThermoanemometer very small air flows can also be measured (e.g. draft mea

Rotating VanesDesignOur rotating vanes are sensitive transducers with diamond bearings that are very precisely adjusted. This ensures high accuracy.

3Volume Flow Measurement 3.5.5 Volume Flow MeasurementFor determining the volume flow V in ventilating channels the medium flow ve-locity is multip

Volume Flow MeasurementDetermination of the Average Flow VelocityThe most important parameter for the measurement of the volume flow is the average f

3Volume Flow Measurement ALMEMO® Manual 3-5-23

Volume Flow MeasurementProcedure:If the measurements are performed according to the guidelines VDI/VDE 2640 the following notes must be observed:- De

3Selecting the Right Flow Sensor The following pictures are guidelines for correct installation of air velocity trans-mitters. Reliable measure-

Thermoanemometer3.5.2 ThermoanemometerThermistors and hot-wire anemometers are highly sensitive sensors that can also measure very small air velociti

3Thermoanemometer Thermoanemometer FVA935-THxThe air velocity sensor is a hot film anemometer. An elec-trical current is increasing the t

Thermoanemometer Temperature: 22 °C ± 2 K Atmospheric humidity: 45 ±10 % r.H. (non-condensing) Atmospheric pressure: 1013 mbarPower supply: 6

3Thermoanemometer Thermoanemometer FV A605-TAFor measuring the air velocity the ALMEMO® range of sensors includes rotat-ing vanes, Pitot tubes and

ThermoanemometerTwo mechanical types are available with two different measuring ranges:Unidirectional (sensitive in one direction) with a protected m

3Thermoanemometer Fühlerschutz:FV A605 TAxO1.When in meas. position, hold sensor tip at the knurled handle band (a).2.Turn the blue sensor handle (