S 421 Flow/Consumption sensor (Inline-sensor)
Features S 421
- Pipes sizes available: DN32, DN40, DN50, DN65, DN80
- Process connections available: R thread, flange EN1092-1, ANSI/B16.5
- Exchangeable sensor unit (easy sensor swap)
- Integrated flow conditioner –> no straight inlet requirements
Common Features S 401 & S 421
- Measures standard flow, mass flow, consumption and temperature
- Thermal mass flow, independent of pressure and temperature changes
- IP65 casing provides robust protection in rough industrial environment
- Very fast response time
- High accuracy and wide measuring range
- Isolated mA and pulse output signals or Modbus/RTU interface
- Selectable gas type (some gases require real gas calibration!)
- App for mobile phones and tablets for sensor settings via BlueTooth
- Sensor can be calibrated in 2 different gases

Volumetric flow ranges S 421
Connection | thread | DN | Measuring range from to |
---|---|---|---|
* | 1¼” | DN32 | 2 … 500 m³/h |
* | 1½” | DN40 | 3 … 700 m³/h |
* | 2” | DN50 | 4 … 1000 m³/h |
* | 2½” | DN65 | 6 … 1500 m³/h |
* | 3” | DN80 | 8 … 2500 m³/h |


Technical data S 401/421 | |
---|---|
Accuracy | 1.5% of reading + 0.3% full scale Optional 1% of reading |
Repeatability | 0.25% of reading |
Sampling rate | 10 samples / sec |
Reference conditions |
Can be set by user. Standard conditions are Ps = 0.1 MPa and Ts = 20 °C |
Operating temperature |
-30 °C … +140 °C fluid temperature -30 °C … +70 °C casing -10 °C … +50 °C casing with display |
Operating pressure |
S 401: 0 … 5.0 MPa (>1.6 MPa need installation device) S 421: 0 … 1.6 MPa |
Analogue output |
Signal: 4 … 20 mA, isolated Scaling: 0 … max flow Max load: 250R |
Pulse output | Signal:Isolated switch output, normally open, Max 30 VDC, 20 mA Scaling:1 pulse per consumption unit |
Modbus/RTU | Isolated RS-485 with Modbus/RTU protocol |
Power supply | 12 … 30 VDC / 200 mA |
Wetted material | Stainless steel 1.4404 (SUS 316L) |