RQ 30 Non-Contact Radar Discharge Measurement System
The availability of real-time discharge data has become increasingly important to companies who require detailed data quickly for optimal water management strategies. The conventional method is the development of a relation called “stage-discharge rating” by…
Points of Interest:
- Easy to install
- Non-contact, Real-time discharge measurement
- Robust Construction
- Measures Water level, velocity and calculates discharge
- Maintenance free operation
- Interfaces: 1 x SDI-12 and 1 x RS485 (Optional 4-20mA)
- Operating Temperature -35° C to 60 °C (-31 °F to 140 °F)
- Adjustable Bandwidth to suit water flow
- Measurement time 0 to 240 seconds
The availability of real-time discharge data has become increasingly important to companies who require detailed data quickly for optimal water management strategies. The conventional method is the development of a relation called “stage-discharge rating” by taking periodic measurements of the discharge using mechanical or acoustic current meters for a range of stages. Complex flow conditions may negate stable stage-discharge ratings and make the use of conventional methods impractical or impossible. These conditions include flow reversals, backwater effects, and hysteresis effects.
The RQ 30 radar sensor measures the stage and the flow velocity and can be used to produce discharge records at stations where conventional methods cannot be used. Furthermore it allows direct calculation of the discharge in the sensor. Two techniques of contact free radar measurement are combined in one system.
The determination of the flow velocity is based on the principle of Doppler frequency shift. The water level is determined by transit time measurement. The measurement values are output via a serial interface, SDI-12 or as analog current signals of 4 to 20mA. This allows a simple adoption into any measurement system. The system is installed simply without constructional changes of the channel itself. Existing bridges or buildings can be used to mount the system. The contact free radar technique guarantees a maintenance free operation over years and is the perfect discharge radar for flood warning.
Fields of Application
The RQ-30 enables discharge measuerment for rivers, streams, open channels and canals for which continuous monitoring is desired. Thanks to the non-contact radar technology the measuring equipment is not susceptible to contamination, debris or driftwood in the water. Furthermore, the non-contact measurement warrants very low maintenance and fail-safe operation especially during high water or flooding.
The sensor can be simply mounted on bridges, on the roofs of closed canals or channel superstructures. The bed of the water should be as stable as possible in order to warrant consistent measurement. A visible swell must be evident on the surface of the water.
The non-contact radar technology determines the water surface flow velocity using the Doppler frequency shift method and furthermore the water level is established by a travel time measurement. With known cross section profile the discharge Q of the water can then be calculated on basis of the continuity equation: Q = vm · A (h)