Accurate Flow and Consumption Measurement
High measurement accuracy of up to ±1.5% of reading (optional ±1%) ensures reliable monitoring of compressed air and technical gas flow and consumption.
CS Instruments – VA 500
Highly accurate thermal insertion flow sensor for reliable flow and consumption measurement, with installation and removal under pressure.
| Measuring Principle Thermal mass flow |
| Medium Compressed air and technical gases |
| Measuring Range 1/2″ to DN 300+ |
| Accuracy ±1.5% of reading (optional ±1%) |
| Operating Pressure -1 to 50 bar |
| Outputs / Communication RS 485 (Modbus RTU), 4–20 mA, pulse output |
| Special Feature Installation and removal under pressure |
| Measuring Principle Thermal mass flow |
| Medium Compressed air and technical gases |
| Measuring Range 1/2″ to DN 300+ |
| Accuracy ±1.5% of reading (optional ±1%) |
| Operating Pressure -1 to 50 bar |
| Outputs / Communication RS 485 (Modbus RTU), 4–20 mA, pulse output |
| Special Feature Installation and removal under pressure |
- Standard Measuring Range Version (92.7 m/s)Standard version suitable for most compressed air and gas flow measurement applications.
- G 1/2″ Threaded Connection (Male Thread)Standard connection for installation through a 1/2″ measuring point (e.g. ball valve).
- Integrated DisplayBuilt-in indication of flow and totalizer values (e.g. m³/h and m³) for quick local readings.
- RS 485 (Modbus RTU)Industrial digital interface for connection to control systems or data loggers.
- Standard AccuracyMeasurement accuracy of ±1.5% of reading and ±0.3% of full scale.
- For Non-Hazardous AreasVersion designed for standard industrial environments without Ex approvals.
- Maximum Operating Pressure up to 50 barSuitable for a wide range of industrial systems (additional protection is recommended at higher pressures).
| Parameter | 120 mm | 160 mm | 220 mm | 300 mm | 400 mm | 500 mm | 600 mm | 700 mm |
|---|---|---|---|---|---|---|---|---|
| Parameters (Basic) | m³/h, l/min (1000 mbar, 20 °C) for compressed air; Nm³/h, Nl/min (1013 mbar, 0 °C) for gases | |||||||
| Displayed Units (Configurable) | m³/h, m³/min, l/min, l/s, ft/min, cfm, m/s, kg/h, kg/min, g/s, lb/min, lb/h | |||||||
| Settings via Keypad | Pipe diameter for flow calculation, counter reset, reference conditions (°C/mbar), 4–20 mA scaling, pulse value | |||||||
| Sensor | Thermal mass flow sensor | |||||||
| Measured Medium | Air, gases | |||||||
| Gas Types (Configurable) | Air, nitrogen, argon, helium, CO₂, oxygen, vacuum | |||||||
| Measuring Range | Depends on pipe diameter (see manufacturer table) | |||||||
| Accuracy (Standard) | ±1.5% of reading + ±0.3% of full scale | |||||||
| Accuracy (Optional) | ±1% of reading + ±0.3% of full scale | |||||||
| Operating Temperature (Sensor Tube) [°C] | -30 … +110 | |||||||
| Operating Temperature (With Pressure Measurement) [°C] | -20 … +85 | |||||||
| Operating Temperature (Housing) [°C] | -20 … +70 | |||||||
| Operating Pressure [bar] | -1 … 50 (additional high-pressure protection recommended above 10 bar) | |||||||
| Digital Interfaces | RS-485 (Modbus RTU) as standard; optional Ethernet (PoE), M-Bus, or IO-Link | |||||||
| Analog Output | 4–20 mA for m³/h or l/min | |||||||
| Pulse Output | 1 pulse per m³ or liter (galvanically isolated); configurable pulse value; can also be used as an alarm | |||||||
| Power Supply | 18 … 36 VDC, 5 W | |||||||
| Load | < 500 Ω | |||||||
| Housing | Polycarbonate (IP65) | |||||||
| Sensor Tube Material | Stainless steel 1.4301 | |||||||
| Standard Installation Length [mm] | 220 | |||||||
| Sensor Tube Diameter [mm] | Ø 10 | |||||||
| Mounting Thread | G 1/2" (male thread) | |||||||
| Housing Diameter [mm] | Ø 65 | |||||||
| Mounting Position | Any | |||||||
Why Choose the VA 500?
Installation and Removal Under Pressure
The probe can be installed and removed while the system is operating. A safety ring prevents uncontrolled ejection of the probe due to system pressure.
Extremely Wide Measuring Range
The wide measuring range allows operation even at very high flow rates in smaller pipe diameters – from 1/2″ up to DN 300 and larger.
Integrated Temperature and Pressure Measurement
Temperature measurement is included as standard, while an optional integrated pressure sensor enables even more accurate calculations and system diagnostics.
Industrial Communication and Analog Outputs
RS 485 (Modbus RTU) is included as standard. Optional interfaces include 4–20 mA outputs, pulse output, Ethernet, M-Bus and IO-Link.
Complete Application Flexibility
Pipe diameter, reference conditions, 4–20 mA scaling and pulse values can be configured directly through the integrated keypad and display.
Energy Industry
Energy MonitoringReliable measurement of air and gas flows to support energy monitoring and improve process efficiency.
Compressor Stations (FAD)
FAD MeasurementMeasurement of Free Air Delivery (FAD) directly in pipelines, even while the system is operating.
Chemical Industry
Process GasesAccurate flow measurement of technical gases for stable and safe chemical processes.
Food & Beverage Industry (N₂ / CO₂)
Inert GasesMonitoring nitrogen and CO₂ consumption in packaging, cooling and protective atmosphere applications.
Automotive Industry
Process AirReliable measurement of air and gas flow in manufacturing, assembly and painting processes.
Aerospace Industry
Critical ProcessesHigh measurement accuracy for flow monitoring in demanding and safety-critical applications.
Metallurgy & Welding
Welding GasesFlow measurement of shielding and process gases for stable welding and metallurgical operations.
Natural Gas & Steam
Industrial MediaMonitoring industrial gas and process media flows for energy and technological applications.
Measuring devices
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Where to find us
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