Water Flow Monitoring

Application Background

Simply recording water depth does not provide a reliable measure of water flow, for example, depth may vary while flow remains constant. In such cases it is essential to measure depth and velocity and then determine the flow measurement.

Unidata’s Starflow Ultrasonic Doppler instrument is ideal for smaller open channel and pipe measurements as it is a complete hydrographic data collection system. Starflow measures water velocity, depth, flow and temperature, enabling you to do a complete stream study with a single instrument.

Starflow operates in a wide range of water qualities from fresh streams to primary sewerage channels. It measures both forward and reverse flows, and is particularly useful at sites where a stable stage / velocity relationship does not exist. For very small flow monitoring the Unidata Tipping Bucket Flow Gauge can be used.

Application Detail

Open channels, partly filled pipes, and natural streams have very complex velocity characteristics. Turbulence, waves, stream slope, bed and wall unevenness, rocks and debris, all combine to create an unpredictable velocity profile. To account for these effects Starflow analyses up to one thousand separate velocity measurements and statistically determines the mean velocity. This approach provides a good “average velocity” even under difficult conditions.

Note, however, that Starflow is not a “current profiler”, that is, it does not record a detailed velocity profile.
The Starlog companion software allows a user to define the stream, channel or pipe profile, so that the velocity and depth readings can be converted to a true flow reading.
Starflow contains a micrologger with 512kb of memory; enough for 250,000 measurements. It will acquire instantaneous, maximum, minimum and averaged readings. Starflow is equipped with the SDI-12 communications facility, intelligent battery supervision and an interface to a telemetry system, such as Neon.

Starflow Instrument can connect to an SDI-12 Data Recorder as a slave or it can act as an SDI-12 Data Recorder master to which other SDI-12 instruments can be connected. You will generally mount the Starflow on (or near to) the bottom of the stream, pipe or culvert where you are measuring flow, however you can also mount it on the side of larger channels.

A single cable connects the instrument to a 12VDC power source. The unit also provides a control output for initiating a water-sampling unit. The sampling control is fully programmable and can be based on flow, velocity, depth or a combination of these conditions. By connecting a rain gauge you can make a complete storm water monitoring system.

Starflow can be equipped with the 6526LCD Starflow Liquid Crystal Display Module to display the values obtained from the most recent scan on demand. The 6526LCD is packaged in a compact weatherproof polycarbonate enclosure, fitted with pre-wired SQL type connectors.

A Neon Remote logger can be connected with the Starflow Instrument in order to record and transmit measured perimeters to a Neon Server routinely. When the data arrives at the Neon Server, it can be viewed on a standard web browser. The data can be checked automatically for any out of limit readings and an appropriate alarm action can be issued.

Typical Configuration

Options for Application Specific Instruments / InputsUnidata Part NumberDescription
Ultrasonic Doppler SDI-12 Instrument - velocity, depth and temperature6527Starflow QSD Ultrasonic Doppler SDI-12/MODBUS Instrument
Tipping Bucket Flow Gauge6506GFlow Gauge 75ml
Tipping Bucket Flow Gauge6506HFlow Gauge 130ml

Options for Neon Telemetry - NRL / NRT / RTU / Field UnitsUnidata Part NumberDescription
Industrial (Metal Enc) Neon Remote Logger 16 Channels3016Options Available: 3G/4G Cellular, Ethernet, Inmarsat, Iridium SBD and LoRa
Industrial (Metal Enc) Neon Remote Logger 8 Channels3008Options Available: 3G/4G Cellular, Ethernet, Inmarsat, Iridium SBD and LoRa
Industrial (Metal Enc) Neon Remote Logger 4 Channels3004/3006Options Available: 3G/4G Cellular, Iridium SBD and LoRa
Neon Remote Logger (Polycarbonate Enc) 4 Channels M Series3004M/3006MOptions Available: 3G/4G Cellular, Microsatellite, Iridium SBD and LoRa
Equatorial Orbit Satellite - Inmarsat2018F-AB0-1 or 3NRT Ethernet with single or triple Ethernet Ports with three Li Batteries
NRT Field Termination Strip2103F2018F and 2022 NRT FTS
NRT Firmware Option2303A-8M8M Extended Memory Option
NRT Firmware Option2303A-8M-CAM8M Extended Memory & Serial Camera Option
NRT Firmware Option2303A-CAMSerial Camera Option

Options for Neon Application Software - Customer ServerUnidata Part NumberDescription
Neon Application Software2302ANeon Server Software Licence Incl 5 NAL
Neon Application Software2302A-10Additional 10 NRT Access Licences
Neon Application Software2302A-20Additional 20 NRT Access Licences
Neon Application Software2302A-50Additional 50 NRT Access Licences

Options for Neon Application Software - Unidata ServerUnidata Part NumberDescription
Neon Application Software2301ANeon Data Initial Subscription Setup Fee
Neon Hosting Service2301A-01Neon Data Service Fee for 1-50 NRTs
Neon Hosting Service2301A-02Neon Data Service Fee for 51-100 NRTs
Neon Hosting Service2301A-10Neon Data Service Fee Metering

Options for Conventional Dataloggers / Field UnitsUnidata Part NumberDescription
Neon Remote Logger 16 Analog Channels / Touch Screen Display3016-00016 Ch NRL (Superseded Prologger 7001D)
Neon Remote Logger 8 Analog Channels / Touch Screen Display3008-0008 Ch NRL (Superseded Stalogger 6004D)
Neon Remote Logger 4 Analog Channels / Touch Screen Display3004M-0004 Ch NRL (Superseded Micrologger 8010C)
Starlog V4 Management Software6308A-AUEStarlog V4 Full Licence Key