SCHMIDT® Flow Sensor SS 20.400
SCHMIDT® Flow Sensor SS 20.400
SCHMIDT® Flow Sensor SS 20.400
SCHMIDT® Flow Sensor SS 20.400
SCHMIDT® Flow Sensor SS 20.400
SCHMIDT® Flow Sensor SS 20.400

SCHMIDT® Flow Sensor SS 20.400

Thermal flow velocity sensor for uni- or bidirectional measurement of air and gases with simultaneous detection of flow direction.

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Introduction Technical Data

SCHMIDT® Flow Sensor SS 20.400

Thermal flow velocity sensor for uni- or bidirectional measurement of air and gases with simultaneous detection of flow direction.

  • Thermopile head (very fast response time)
  • Flow velocity and switching signals
  • Probe length 130 … 300 mm
  • Measuring ranges 0 … 1 m/s to 0 … 20 m/s
  • Bidirectional measurement (optional)
  • Detection of flow direction (optional)
  • Optimized adjustment for LF-applications (optional)
  • Sensor programming (optional)
  • Cleanroom sensor
  • Extremely compact (electronics is integrated in sensor tube)
  • Sensor element protected against mechanical stress
  • Linear analog output for measured flow velocity
  • Two switching outputs to signal flow direction and threshold
  • Clean rooms and pharma
  • Laminar flow monitoring in flow boxes
  • Monitoring of cleanroom overflow
  • Cooling air monitoring
  • Flow measurement in test benches

SCHMIDT Technology – Simply a question of better measurement

Technical data
Measuring quantity

Standard flow velocity wN based on standard conditions temperature of medium TM
Measured medium Clean air or nitrogen, additional gases on request
Measuring range wN (±)0 … 1 / 2.5 / 5 / 10 / 20 m/s (uni- or bidirectional)
Lower detection limit wN (±)0.05 m/s
 

Measuring accuracy
Standard wN ±(3 % of measured value + [2 % of fmr; min. 0.05 m/s])
High precision (optional) wN ±(1 % of measured value + [2 % of fmr; min. 0.04 m/s])
Response time (t90) wN 1 s (configurable: 0.01 ... 10 s)
 

Operating temperature
Sensor probe 0 … +60 °C
Storage temperature -20 … +85 °C
 

General data
Humidity Measuring mode: Non-condensing (< 95 % RH)
Operating pressure (max.) Atmospheric (700 … 1.300 hPa)
Supply voltage 12 … 26.4 V DC
Current consumption Typical < 35 mA (max. 150 mA, current of switching outputs included)
Analog outputs (wN and TM) 0 … 10 V (RL > 10 kΩ; CL ≤ 10 nF; short-circuit protected)
4 … 20 mA (RL < 300 Ω; CL ≤ 100 nF)
Switching outputs 2 x open collector (at GND), current-limited and short-circuit protected, configurable
-Channel 1 (OC1): Flow direction or threshold value
- Channel 2 (OC2): Threshold value
- External switching voltage / current: Max. 26.4 V DC / 55 mA (typ. 50 mA)
- Hysteresis: 5 % of threshold value (min. ±0.05 m/s)
Electrical connection Plug-in-connector M9, male, 7-pin (shielded), screwed
Maximum cable length Voltage interface: 10 m; current interface: 100 m
Mounting position ±3° relative to flow direction (uni- or bidirectional)
Protection type Sensor probe: IP66; electrical connector: IP67 (with correct attached cable)
Protection class III (SELV) or PELV (EN 50178)
Sensor length 130/200/300 mm
Weight Approx. 60 g max. (L = 300 mm)
 

Material
Sensor head Stainless steel 1.4404
Sensor tube Stainless steel 1.4404
Plug-in connector, nut screw Stainless steel 1.4404
 

Dowloads
Product brochure (02/2023) Dowload PDF
Instructions for use (504301.02G) Dowload PDF
3D-STP data Dowload
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