Exceptional Sensitivity at Low Velocities
Unique sensitivity in the lower measuring range enables accurate measurements from as low as 2 m/s, covering the entire operating range of variable-speed (VSD) compressors.
CS Instruments – VD 550
Robust differential pressure flow sensor for wet compressed air and technical gases, providing flow, consumption, temperature, and pressure measurement with installation under pressure.
| Measuring Range: 2 … 224 m/s / 600 m/s (compressed air) |
| Measuring Range (Gases): 0.04 … 500 mbar differential pressure |
| 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 |
| Media Temperature: -30 … +180 °C |
| Operating Pressure: -1 … +100 bar(g) |
| Protection Class: IP67 |
| Outputs: RS-485 (Modbus RTU), 4–20 mA, pulse |
| Measuring Range: 2 … 224 m/s / 600 m/s (compressed air) |
| Measuring Range (Gases): 0.04 … 500 mbar differential pressure |
| 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 |
| Media Temperature: -30 … +180 °C |
| Operating Pressure: -1 … +100 bar(g) |
| Protection Class: IP67 |
| Outputs: RS-485 (Modbus RTU), 4–20 mA, pulse |
- Differential Pressure Flow Sensor (VD 550)Robust flow sensor for wet compressed air and gases, measuring flow, total consumption, temperature, and pressure.
- Installation Under Pressure via Ball ValveInstallation through a 1/2" or 3/4" ball valve allows mounting and servicing under pressure without shutting down the system.
- Robust Outdoor Housing (IP67)Impact-resistant die-cast aluminum housing with IP67 protection, suitable for outdoor installation.
- Standard Outputs and CommunicationPulse output, RS-485 (Modbus RTU), and 1× 4–20 mA analog output (electrically non-isolated).
| Parameter | VD 550 |
|---|---|
| Measuring Range | 2 … 224 m/s / 600 m/s (compressed air); 0.04 … 500 mbar differential pressure (gases) |
| 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 |
| Media Temperature | –30 … +180 °C |
| Operating Pressure | –1 … +100 bar(g) |
| Ambient Temperature | –20 … +70 °C |
| Protection Class | IP67 |
| Power Supply | 18 … 36 V DC, 5 W |
| Signal Outputs (Standard) | 1× 4–20 mA analog output (electrically non-isolated), pulse output, RS-485 (Modbus RTU) |
| Signal Outputs (Optional) | 2× 4–20 mA active outputs, Ethernet interface (PoE), M-Bus, HART, IO-Link |
Why Choose the VD 550?
Suitable for Very High Flow Rates
The differential pressure measuring principle enables reliable measurement even at extremely high flow velocities and large pipe diameters.
Multiple Measurements in One Device
Measurement of flow, total consumption, temperature, and pressure in a single device provides comprehensive system monitoring without additional sensors.
High-Temperature Measurement
Suitable for demanding applications with media temperatures up to +180 °C, without compromising measurement stability or accuracy.
Wide Pipe Diameter Range
Suitable for pipelines from DN 20 to DN 1500, enabling universal use in compressed air and technical gas systems.
Installation Under Pressure
Installation through a 1/2" or 3/4" ball valve allows mounting and removal of the sensor without shutting down the system.
Robust Industrial Design
Impact-resistant die-cast aluminum housing with IP67 protection ensures reliable operation even in outdoor and harsh industrial environments.
Compressors and Compressed Air Systems
Efficiency / FADAccurate flow measurement directly downstream of compressors for FAD determination, performance monitoring, and optimization of fixed-speed and variable-speed (VSD) compressors.
Energy and Energy Monitoring
Energy EfficiencyUsed for energy audits and monitoring compressed air consumption as one of the key industrial utilities, including loss analysis and system optimization.
High-Flow Industrial Systems
High Flow RatesReliable flow measurement in large pipelines (DN 20 to DN 1500) and at very high flow velocities in demanding industrial processes.
Measuring devices
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Measurement reports, trends, and interpretation of results
Supply, installation, calibration, and service
Where to find us
DirectionsPod lipami 4 · 1370 Logatec, Slovenija
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