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Working Hours

Mon - Fri: 08:00 - 16:00 (EET)
Sat: Closed
Sun: Closed



Models 0101, 5101, 5201

This compact air flow sensor is specially designed for air flow monitoring and provides early warnings of clogged filters. Its compact housing style fits easily into ventilation systems and features an adjustable potentiometer to establish a setpoint. An LED provides visual indication when flow is above or below the setpoint. This airflow sensor is based on the calorimetric principle and is an inexpensive alternative for mechanical flaps and pressure cells. All components of the airflow sensor are incorporated in a compact smooth cylindrical plastic housing. The airflow sensor has a built-in timer that serves as a switch-on delay for the fan or ventilator. During this time the output is closed, the relay is energized which is also visually displayed by means of a simultaneous lighting of a red and a green LED. The switch point can be set by means of a potentiometer and is indicated by a red or green LED. In the case of no flow the red LED lights. If the green LED does not light, the output relay is de-energized. When the airflow monitor detects flow the red LED goes out, the green one lights and the output relay is energized. The output signal is available as a floating NO contact. The length of the airflow monitor allows a maximum immersion of 120 mm into the air duct. It is installed by means of a mounting clamp which is secured to the duct via two self-tapping screws. The airflow sensor can also be used for industrial airflow monitoring, since during the design of the sensor part special emphasis was put on the protection of the PTC's against mechanical destruction by solid particles in the medium. The PTC's are included in the sensor head and are protected against mechanical damage from outside by means of flush mounted metal plates. The metal plates also provide a good heat contact to the medium.


Operating voltage: 24 V DC (model 5101)                            80~250 VAC/DC (model 0101)
output:    Relay output, N/O (relay on with flow present) Medium temperature:    -10 to +50C
Setting range (cm/s):    100…..100 m/s
Function display:    2 LEDs (1 red & 1 green)
Response time (s):    3...60
Protection rating:    IP65
Housing    Body & sensor head: POCAN
connection: 2m PUR 4 x 0.5mm2
Pressure rating (bar)    1
Dimensions    L140 x 23mm dia.

0630-5101     Model 5101
0630-0101     Model 0101

Analogue output model   
Operating voltage    24 V DC + 10%
output    0...10V  analogue
Medium temperature    35...65C
flow range (cm/s)    200…..2000 (1...10V)
Function display    1 green LED
Power On delay (s)    90
Protection rating    IP65
Housing    Body & sensor head POCAN
connection    Cable with Binder plug /
2m ; 4 x 0.5mm2
Pressure rating (bar)    1
Dimensions    L140 x 23mm dia.
0630-5201      Model 5201

Pitot Tubes

type L pitot tubes - With or without temperature compensation
Accuracy :  more than 0,5 % for an alignment with to the fluid axis flow within 12°
Pitot tubes conform to AFNOR.NF.X10.112.norm. Appendix 4 dated 14.9.77.
Type : ellipsoidal head curved NPL
Coefficient : 1,0015.
Quality : Hard stainless steel; 4/4 to AFNOR / Z2.CND.17.12.

type S pitot tubes - With integrated thermocouple K probe
a wide range of high-quality and accurate Pitot tubes, as per the ISO 10780 norm.

Length of the Pitot tubes Type S  Ø 8 mm

  •     500 mm
  •     1000 mm
  •     1500 mm
  •     2000 mm
  •     2500 mm
  •     3000 mm

Sigma air flow measuring blades

Sigma air flow measuring blades are a simple and cost effective method of providing permanent air flow measurement in rectangular or circular ducts. When used with one of our Class 100/200/300 differential pressure device (pressure, transmitter, electronic micromanometer, liquid column manometer, differential pressure switch, ...).

Sigma air flow measuring blades have been designed and manufactured for use in all types of air flow systems. The flow measuring blades, when correctly placed in an air flow, generate a differential pressure, the square root of which is proportional to the air flow.

  •     Sigma air flow measuring blades ensure accurate indication, control or recording of air flow velocity and volume.
  •     Permit velocity measurements from 3 to 100 m/s (9 Pa to 10000 Pa).
  •     Airfoil section limiting differential heads (<3%) and turbulences.
  •     Distribution of the measurement apertures on the airfoil permitting the medium air flow control (average of the differential pressures).

The choice of the number of blades depends on the shape of the duct and the accuracy wished. One or several Sigma blades can be used depending on the applications.

15 standard lengths available:100/125/160/200/250/315/400/500/630/800/1000/1500/2000/2500/3000mm, with others available on request.

applications : air supply systems in laboratories, air conditioning systems, air flow test rigs, fume extraction and exhaust systems, vacuum cleaning systems.

pitot tube accessories

clear & silicone tube
clear tube Ø 5 x 8
for permanent installation (m/l or 25m).
Silicone tube Ø 4 x 7

pipe connectors
Straight connection for Ø 5 x 8 tube. T-connection for Ø 5 x 8 tube. Y-connection for Ø 5 x 8 tube.
Black or white, for test instruments (m/l or 25 m).

Air Flow Sigma Cones for measuring direct air flows in ventilators and HVAC systems
By placing a Sigma Capture Cone  over a diffuser or grille, you can measure air volume in order to verify air flow distribution. The easily observed trend values and fast meter response make the Sigma Cones the preferred instrument for facility engineers.

Airflow Sigma Cones for hotwire anemometers
Cone K35 : 10 @ 400 m³/h - 200 x 200 x 300 mm
Cone K75 : 30 @ 750 m³/h - 300 x 300 x 470 mm.
Cone K120:50 @ 1200m3/h - 450 x 450 mm x 600 mm
Cone K150:10 @  400 m3/h - 550 x 100 mm x 600 mm

Airflow Sigma Cones for 100 mm  vane
Airflow cone for 100 mm  diameter vanes
Cone K25 : 10 @ 400 m3/h - 200 x 200 mm x 330mm
Cone K85 : 10 @ 400 m3/h - 350 x 350 mm x 450mm