SCHMIDT® Flow Sensor SS 20.400

Thermal flow sensor for uni- or bi-directional measurement of the flow rate of air and gases with simultaneous detection of flow direction.

 

  • Thermopile head (very fast response time)
  • Flow and switching signal
  • Probe length 130 … 300 mm
  • Measuring ranges 0 … 1 m/s to 0 … 20 m/s
  • Bi-directional measurement (detection of flow direction, optional)
  • Vertical adjustment (for laminar flow applications, optional)
  • Sensor programing (optional)
  • Cleanroom sensor
  • Extremely compact, because electronics are integrated into the sensor tube.
  • Sensor element in the chamber head and protected against mechanical stress.
  • Linear analog output for measured value output, two switching outputs to output the flow direction and threshold.

 

  • 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

Specifications

Technical data
Measuring quantityStandard flow velocity wN, based on standard conditions 1)
Measured mediumClean air, nitrogen, additional gases on request
Measuring range flow wN0 … 1 / 2.5 / 5 / 10 / 20 m/s
Lower detection limit flow wN0.05 m/s
Measuring accuracy
Standard wN± (3 % of measured value + [2 % of fmr; min. 0.05 m/s]) 1)
High precision (optional) wN± (1 % of measured value + [2 % of fmr; min. 0.04 m/s]) 1)
Response time (t90) wN1 s (configurable: 0.01 ... 10 s)
Operating temperature
Sensor0 … +60 °C
Storage temperature-20 … +85 °C
Material
Sensor headStainless steel 1.4404
Sensor tubeStainless steel 1.4404
Plug connectorStainless steel 1.4404
General data
HumidityMeasuring mode: Non-condensing (< 95 % RH)
Operating pressure (max.)Atmospheric (700 … 1.300 hPa)
Supply voltage12 … 26.4 V DC
Current consumptionTypical < 35 mA (max. 160 mA with switching outputs)
Analog output wN0 … 10 V (RL > 10 kΩ; CL ≤ 10 nF; short-circuit protected)
4 … 20 mA (RL < 300 Ω; CL ≤ 100 nF
Switching outputs2 x low-side driver (open collector at GND), current-limited and short-circuit protected, configurable
Channel 1 (OC): Direction or threshold value; Channel 2 (OC2): Threshold value
External switching voltage / current: Max. 26.4 V DC / 55 mA (typ. 50 mA)
Switching hysteresis: 5 % of threshold value, min. ± 0.05 m/s
Electrical connectionPlug-in-connector M9, male, 7-pin (shielded), screwed
Maximum cable lengthVoltage interface: 10 m
Current inferface: 100 m
Mounting positionArbitrary
Protection type / classIP66 / III or PELV (EN 50178)
Sensor length130 / 200 / 300 mm
WeightApprox. 60 g max. (300 mm sensor length)

1) Standard velocity wN based on standard conditions of 20 °C and 1,013.25 hPa, related to adjustment reference; fmr = final measuring range

Subject to technical changes.

Order information

 DescriptionArticle-Number
Basic sensorSCHMIDT® Flow Sensor SS 20.400, thermopile head
(also available as: ATEX version (cat. 3G, zone2; please refer to SS 23.400)
518 210 -XYDZR-P
 Options
Mechanical typeSensor length 130 mm (only with 0…10V output signal available) 1      
Sensor length 200 mm 2      
Sensor length 300 mm 3      
Measurement rangeMeasurement range 0 … 1 m/s  1     
Measurement range 0 … 2.5 m/s  2     
Measurement range 0 … 5 m/s  3     
Measurement range 0 … 10 m/s  4     
Measurement range 0 … 20 m/s  5     
Measurement direction, adjustment accuracy and calibrationUnidirectional – standard adjustment   1    
Unidirectional default adjustment with factory calibration certificate   6    
Bidirectional – standard adjustment   2    
Bidirectional default adjustment with factory calibration certificate   7    
Unidirectional – high precision adjustment incl. factory calibration certificate   3    
Bidirectional – high precision adjustment incl. factory calibration certificate   4    
Unidirectional – vertical flow adjustment with high precision with factory calibration certificate (only for measuring range 1 m/s)   5    
Analog output0 … 10 V    1
   
4 … 20 mA (not for sensor length 130 mm)    5
   
Representation of directionBidirectional switching output OC 1     1  
Bidirectional: halved analog signal 0 m/s = 12 mA / 5 V     2
  
Unidirectional     3  
Sensor-programmingFactory setting       S
Customer-specific programming of switching polarity, splitting signal and response time       K

Accessories

Connection technology

DescriptionArticle-Number
Coupler socket, 7-pin, with soldering sleeves for cable Ø 0.14 mm2535 278
Connection cable with coupler socket, 5 m length, open cable ends, material PUR535 279
Connection cable with coupler socket, length ________ m,
open cable ends (length 2 … 100 m; 1-m-steps)
505 911 - 4
Connection cable with angled socket, 7-pin, length 10 m, open cable ends535 281
Power supply 24 V/1 A DC (output), 115/230 V AC voltage supply535 282

Mounting and fixing technology

DescriptionArticle-Number
Wall mounting flange, stainless steel, clamping ring PTFE520 181
Compression fitting stainless steel G½, atmospheric pressure532 160
Wall mounting bracket, material aluminium anodized503 895
Mounting flange stainless steel 1.4404551 740
Assembly kit for pipe assembly suitable for MD 10.010/10.015 including pipe clamps and collar for adjustment to the pipe diameter531 394

Measured value display

DescriptionArticle-Number
SCHMIDT® LED display MD 10.010 in wall housing to show volume flow and flow velocity, 85 … 250 V AC and sensor power supply527 320
SCHMIDT® LED display MD 10.010, similar to 527 320 but with 24 V DC voltage supply528 240
SCHMIDT® LED-display MD 10.015; similar to 527 320 but with an additional sum function and a second measuring input527 330
SCHMIDT® LED display MD 10.015, similar to 527 330 but with 24 V DC voltage supply528 250

Miscellaneous

DescriptionArticle-Number
Measuring Section Calibrator set (8 / 12 / 16 mA)546 741 - 4

Downloads

Back to Top