RQ-30d Discharge Radar Sensor
Discharge measurement for wide rivers with inhomogeneous distribution of flow velocity With the system of one master-radar sensor and several slave-radar sensors the velocity is measured at several spots throughout the whole water cross-section. Therefore a… Read more
GENERAL |
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| Dimensions | master: 338 mm x 333 mm x 154 mm | slave: 175 mm x 154 mm x 246 mm |
| Total weight | master: 5.4 kg | slave: 2.7 kg |
| Protection class | IP 67 |
| Power supply | 6 ... 30 V |
| Power consumption at 12V | standby approx. 1mA; active operation approx. 140mA |
| operating temperature | - 35 ... 60°C |
| Miscellaneous | over voltage protection, reverse power protection, lightning protection |
WATERLEVEL MEASUREMENT |
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| Measuring range | 0 ... 15 m standard version / 0 ... 35 m extended version |
| Resolution | 1 mm |
| Radar frequency | 26 GHz (K-Band) |
| Radar opening angle | 10° |
VELOCITY MEASUREMENT |
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| Measuring range | 0.08 ... 16 m/s (depending on flow conditions) |
| Accuracy | +/- 0.01 m/s; +/- 1 % FS |
| Resolution | 1 mm/s |
| Direction recognition | +/- |
| Measuring duration | 5 ... 240 sec. |
| Measuring interval | 8 sec. ... 5h |
| Measuring frequency | 24 GHz (K-Band) |
| Radar opening anlge | 12° |
| Distance to water surface | 0.50 ... 35 m |
| Minimum swell needed | 3 mm |
AUTOMATIC VERTICAL ANGLE COMPENSATION |
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| Accuracy | +/- 1° |
| Resolution | +/- 0.1° |
INTERFACE |
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| Interface | 1x SDI-12 1 x RS 485 or Modbus |
| Transfer rate | 1.2 to 115.2 kBd |
| Protocol | diverse ASCII-protocols |
| Output | discharge rate, flow velocity, waterlevel, quality parameters |
Discharge measurement for wide rivers with inhomogeneous distribution of flow velocity
With the system of one master-radar sensor and several slave-radar sensors the velocity is measured at several spots throughout the whole water cross-section. Therefore a very high accuracy of the discharge measurement is achieved also for very wide water bodies.
Measuring principle
For the RQ-30d (in comparison to the RQ-30) the measuring principle was enhanced: Here the river is split into multiple sections and from each one a partial velocity measurement is taken. One sensor, the master device, additionally measures the water level and distributes this information to all the other devices (= slaves) in the system. Now they are able to calculate the partial dicharge rate per section. Summing up all partial amounts of discharge results in the total discharge at the actual site – continuously, with non-contact to the water and with increased accuracy. The RQ-30d system can be operated with up to seven slave devices at the maximum.
- Discharge measurement with high accuracy – ideal use for very wide rivers with inhomogeneous velocity distribution
- One water level measurement and multiple, individual velocity measurements
- Well proven RQ-radar technique: non-contact measurement, maintenance free system, flood-proof
- No structural work is necessary in the water
- Recognition of flow direction and hysteresis effects
- Measurement in tidal waters
- Measurement in backwater situations
- Measures even where weed growth prevails and sensor is not affected by turbidity
- Measuring range 0.08 ... 16 m/s (depending on the flow conditions)
- Analogue outputs from 4 to 20 mA (optional)
The main advantage of the RQ-30d is that the discharge can be measured more precisely, especially in rivers and streams where the flow velocity is distributed inhomogeneously over the cross-section. Varying velocities can be observed particularly in very broad streams as well as in situations, where the measuring site is located close to a river bend, an incoming river or watergates. In order to capture the complete flow-profile even more accurately, the RQ-30d system measures multiple individual flow velocities dispersed over the width of the body of water.

