Compact and Ready to Use
Compact inline flow meter ready for immediate operation, with integrated temperature and pressure compensation for minimal installation effort.
CS Instruments - VD 520
Compact flow meter based on averaging Pitot tube technology.
| Measuring Range: 2 … 224 m/s / 600 m/s (compressed air) |
| Measured Medium: Air and gases |
| Accuracy: ± 1.5% of measured value |
| Measurement Principle: Differential pressure |
| Turndown Ratio: 1:100 / 300 |
| Response Time: t99 < 1 s |
| Operating Pressure: -1 … 30 bar(g) |
| Outputs: RS-485 (Modbus RTU), 4–20 mA, pulse |
| Measuring Range: 2 … 224 m/s / 600 m/s (compressed air) |
| Measured Medium: Air and gases |
| Accuracy: ± 1.5% of measured value |
| Measurement Principle: Differential pressure |
| Turndown Ratio: 1:100 / 300 |
| Response Time: t99 < 1 s |
| Operating Pressure: -1 … 30 bar(g) |
| Outputs: RS-485 (Modbus RTU), 4–20 mA, pulse |
- Inline Differential Pressure Flow Meter (VD 520)Compact ready-to-use version with integrated pressure and temperature compensation, providing flow, consumption, temperature, and pressure measurement.
- Process Connection Options: Threaded or FlangedAvailable with R male thread, NPT male thread, or flanges (DIN EN 1092-1, ANSI 16.5 Class 150 / 300).
- Selectable Measuring Section (DN)Standard measuring sections DN 15 / 20 / 25 / 32 / 40 / 50 (threaded) and DN 65 / 80 (flanged only).
- Analog and Digital Outputs (Standard Version)RS-485 (Modbus RTU), 4–20 mA analog output, and pulse output are included as standard.
| Parameter | VD 520 |
|---|---|
| Measuring Range | 2 … 224 m/s (compressed air), optionally up to 600 m/s; 0.04 … 500 mbar differential pressure (gases) |
| Measured Medium | Air and technical gases |
| Accuracy | ± 1.5 % of measured value |
| Measurement Principle | Differential Pressure |
| Turndown Ratio | 1 : 100 / 300 |
| Response Time | t99 < 1 s |
| Media Temperature | –30 … +80 °C |
| Operating Pressure | –1 … +30 bar(g) |
| Ambient Temperature | –20 … +70 °C |
| Power Supply | 18 … 36 V DC, 5 W |
| Signal Outputs (Standard) | RS-485 (Modbus RTU), 4–20 mA, pulse output |
| Signal Outputs (Optional) | Ethernet interface (Modbus TCP / PoE), M-Bus |
Why Choose the VD 520?
Multiple Measurements in One Device
Measures flow, total consumption, temperature, and pressure in a single device, reducing the need for additional sensors.
High Accuracy at Low Velocities
The highly sensitive differential pressure sensor ensures very accurate measurements even at velocities below 2 m/s.
Wide Measuring Range
Very large measuring range and extended turndown ratio thanks to measuring sections with reduced internal diameters.
Shorter Inlet Sections
The use of an averaging Pitot tube significantly reduces the required straight inlet lengths in the pipeline.
Robust Industrial Design
The rugged design without moving parts ensures long service life and reliable operation even in demanding industrial environments.
Easy Calibration
The removable sensor head allows simple calibration and servicing without removing the entire measuring section.
Compressors and Compressed Air Systems
Efficiency / FADAccurate flow measurement for compressor performance monitoring, FAD determination, and optimization of fixed-speed and variable-speed (VSD) compressed air systems.
Energy and Energy Monitoring
Energy EfficiencyMeasurement of compressed air consumption for energy audits, energy cost monitoring, loss analysis, and industrial system optimization.
Technical Gases and Process Industry
GasesSuitable for flow measurement of various technical gases in industrial processes requiring accurate measurements under different pressures, temperatures, and operating conditions.
Measuring devices
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Where to find us
DirectionsPod lipami 4 · 1370 Logatec, Slovenija
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