Velocity Radar RG-30/30A - Accurate Flow Measurement

VELOCITY RADAR RG-30 / RG-30A

RADAR SENSOR FOR CONTACT-FREE VELOCITY MEASUREMENT

The flow velocity sensor RG-30 has been designed for contact-free measurements of the surface flow velocity of rivers and channels by means of radar technology.

FEATURES AND ADVANTAGES

Maintenance free
No structural work is necessary in the water
Simple integration into existing systems
No threat to the system through flooding
Low power consumption
Recognition of flow direction
Measuring range 0.08 … 16 m/s (depending on the flow conditions)
Near blanking zone 0.5 m
Non-contact and fast measurement
Own measurement interval or externally triggered
Independent of environmental influences

Description

FIELDS OF APPLICATION

The radar sensor RG-30 is used for hydrography and water management. It is applied for example in open rivers, streams, or channels. It is especially suitable for measurement tasks where the usage of conventional respectively contact intense measurement systems is problematic. For example, measuring spots that are hard to reach or carry highly turbid water. It is installed outside the water and measures without direct contact with the same. Hence, the system requires no maintenance and works reliably even during high flow, floodings, or despite debris, driftwood, or high turbidity.

IMPLEMENTATION

The sensor impresses with its low power consumption and its high reliability for permanent recording of the flow velocity. The compact design and the contact-free measurement principle by means of radar technology allow easy and uncomplicated mounting and usage.

MEASURING PRINCIPLE

The measurement of the flow velocity is based on the principle of the Doppler frequency shift. The sensor emits a radar signal and compares its frequency with one of the reflected signals from the water surface. The frequency is shifted proportionally to the surface flow velocity. Those signals are collected, evaluated and the medial surface flow velocity is determined.

TECHNICAL DETAILS

GENERAL

Dimensions 241 mm x 246 mm x 154 mm
Total weight 2.7 kg
Protection class IP 67
Power supply 6 … 30 V
Power consumption at 12V standby approx. 1 mA; active operation approx. 110 mA
Operating temperature -35 … 60°C
Miscellaneous Protection over-voltage protection, reverse power protection, lightning protection

VELOCITY MEASUREMENT

Measurement range 0.08 … 16 m/s (depending on flow conditions)
Accuracy +/- 0.01 m/s; +/- 1 % FS
Resolution 1 mm/s
Direction recognition +/-
Measurement duration single measurement 5 … 240 sec.
Measurement interval 8 sec. … 5h
Radar frequency 24 GHz (K-Band)
Radar opening angle 12°
Distance to water surface 0.50 …130 m
The necessary minimum swell is 3 mm

AUTOMATIC VERTICAL ANGLE COMPENSATION

Accuracy +/- 1°
Resolution +/- 0.1°

INTERFACE

Analogue output (only at RG-30a) velocity 4 … 20 mA; 0 … 10 m/s configurable
Interface 1 x RS 485 or Modbus; 1 x SDI-12
Digital input 1 x trigger input low: 0 … 0.6 V; high: 2 … 30 V