High Measurement Accuracy Across the Entire Range
Excellent measurement accuracy, even at very low flow rates, enables reliable monitoring of consumption and leak detection in compressed air and gas systems.
CS Instruments – VA 520
Inline thermal flow meter with an integrated measuring section for highly accurate consumption measurement and leak detection.
| Meter Type Inline Flow Meter (Integrated Measuring Section) |
| Measuring Principle Calorimetric / Thermal Mass Flow |
| Outputs 4–20 mA + Pulse Output (Galvanically Isolated) |
| Communication RS-485 (Modbus RTU), optional Ethernet/PoE, M-Bus, IO-Link |
| Application High Accuracy Even at Low Flow Rates (Leak Detection) |
| Pressure Drop Negligible |
| Display 2 Values Simultaneously, Rotatable by 180° |
| Option Integrated Pressure Sensor |
| Meter Type Inline Flow Meter (Integrated Measuring Section) |
| Measuring Principle Calorimetric / Thermal Mass Flow |
| Outputs 4–20 mA + Pulse Output (Galvanically Isolated) |
| Communication RS-485 (Modbus RTU), optional Ethernet/PoE, M-Bus, IO-Link |
| Application High Accuracy Even at Low Flow Rates (Leak Detection) |
| Pressure Drop Negligible |
| Display 2 Values Simultaneously, Rotatable by 180° |
| Option Integrated Pressure Sensor |
- Inline Meter with Defined Measuring SectionIntegrated measuring section with inlet and outlet flow conditioning ensures high measurement accuracy and repeatability.
- Modbus-RTU (RS-485)Digital interface for connection to PLCs, BMS systems, or Energy Management Systems (EMS), including remote diagnostics and configuration.
- 4–20 mA Analog OutputOutput for instantaneous flow rate (e.g. m³/h or l/min) for easy integration into existing control systems.
- Pulse Output (Galvanically Isolated)Pulse output for total consumption (counter) with configurable pulse value; can also be used as an alarm output.
- Dual-Value DisplaySimultaneously displays current flow rate and total consumption; temperature measurement is also included.
- Integrated KeypadQuick counter reset, unit selection, zero adjustment, and leak flow volume suppression functions.
- Easy MaintenanceThe measuring unit can be unscrewed; removal of the complete measuring section or a bypass is not required. The sensor can be removed and cleaned.
| Parameter | R 1/4" | R 3/8" | R 1/2" | R 3/4" | R 1" | R 1 1/4" | R 1 1/2" | R 2" | DN 15 | DN 20 | DN 25 | DN 32 | DN 40 | DN 50 | DN 65 | DN 80 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Parameters (Standard) | m³/h, l/min (1000 mbar, 20 °C) for compressed air; Nm³/h, Nl/min (1013 mbar, 0 °C) for gases | |||||||||||||||
| Display 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 | |||||||||||||||
| Sensor | Thermal Mass Flow Sensor | |||||||||||||||
| Measured Medium | Air, gases | |||||||||||||||
| Gas Types (Configurable) | Air, nitrogen, argon, CO₂, oxygen | |||||||||||||||
| Measuring Range | Depending on measuring section size (manufacturer's table) | |||||||||||||||
| Accuracy (Standard) | ±1.5% of reading + ±0.3% of full scale | |||||||||||||||
| Accuracy (Optional) | ±1% of reading + ±0.3% of full scale | |||||||||||||||
| Operating Temperature [°C] | -30 … +80 | |||||||||||||||
| Operating Temperature (with Pressure Measurement) [°C] | -20 … +80 | |||||||||||||||
| Operating Pressure [bar] | -1 … 16 (optionally up to PN 40) | |||||||||||||||
| Digital Interfaces | RS-485 (Modbus RTU); optional Ethernet (PoE), M-Bus, 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 relay | |||||||||||||||
| Power Supply | 18 … 36 VDC, 5 W | |||||||||||||||
| Load | < 500 Ω | |||||||||||||||
| Housing | Polycarbonate (IP65) | |||||||||||||||
| Measuring Section Material | Stainless steel 1.4404 or 1.4301 | |||||||||||||||
| Mounting Position | Any orientation | |||||||||||||||
Why Choose the VA 520
Inline Measurement Without a Bypass Line
The integrated measuring section with defined inlet and outlet sections allows easy installation directly into existing pipelines without requiring an additional bypass line.
Negligible Pressure Drop
The calorimetric measuring principle without mechanical moving parts ensures an extremely low pressure drop and minimal impact on the process.
Ideal for Leak Detection
High resolution in the lower measuring range enables effective leak detection and energy consumption optimization.
Dual Display and Rotatable Screen
The display simultaneously shows current flow, total consumption, and temperature, and can be rotated by 180°, enabling easy reading even in ceiling-mounted installations.
Advanced Configuration and Diagnostics
Counter reset, unit selection, zero adjustment, and diagnostic functions (min/max values, errors, service data) are accessible locally or via communication interfaces.
Industrial Communication and Integration
Support for Modbus-RTU, Ethernet (PoE), M-Bus, and IO-Link enables easy integration with energy management systems, BMS platforms, or PLC controllers.
Robust Industrial Design
An IP65 housing and stainless-steel measuring section ensure reliable operation in demanding industrial environments.
Energy
Energy MonitoringReliable measurement of air and gas flow rates 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 remains in operation.
Chemical Industry
Process GasesAccurate flow measurement of technical gases for stable and safe chemical processes.
Food 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 monitoring flow rates in demanding and safety-critical applications.
Metallurgy and Welding
Shielding GasesMeasurement of shielding and process gas flow rates for stable welding and metallurgical processes.
Natural Gas and Steam
Industrial UtilitiesMonitoring industrial gas and process media flow rates for energy and technological applications.
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