Starflow Ultrasonic Doppler Instrument

Model 6526

  • Overview

    Unidata ultrasonic Doppler instrument is a compact, easy-to-use system for measuring the velocity and depth of water in rivers and streams, open drainage channels, and large pipes. It is suitable for use in a wide range of water qualities ranging from sewage and wastewater to clean streams, potable water and even seawater.

    The instrument measures forward and reverse flow conditions and may be programmed to computer flow rate and total flow in pipes and open channels.

    The ultrasonic transducer assembly is profiled to reduce flow disturbance. It is designed to be placed at (or near) the bottom of the water channel for upstream measurement. A single cable connects the instrument to a 12V DC power source.

    Water velocity is measured by the ultrasonic Doppler principle which relies on suspended particles or small air bubbles in the water to reflect the ultrasonic detector signal. The instrument will not operate in very clean, degassed water. Water depth is gauged by a hydrostatic pressure sensor, referenced to atmospheric pressure through the vented power and signal cable.

    Model Depth Resolution
    6526J-51 0 to 5m 2.5mm for 0 to 2.5m
    5mm for 2.5 to 5m

    Starflow Ultrasonic Doppler Velocity, Depth and Flow Instrument

  • Specifications

    Physical specifications

    Material: PVC body, Marine Grade 316 Stainless Steel Mounting Bracket
    Size: 290mm x 70mm x 30mm (LxWxH)
    Weight: 2kg with 15m of Cable
    Operating temperature: 0°C to 60°C water temperature

    Velocity, Depth and Flow specifications

    Velocity Range: 21mm/s to 4500mm/s bi-directional
    Velocity Accuracy: 2% of measured velocity
    Velocity Resolution: 1mm/s

    Depth Range:
    0m to 5.0m
    Depth Accuracy: Typical ± 0.25%

    Temperature: -17°C to 60°C
    Temperature Resolution: 0.1°C

    Flow Computation: Flow rate, totalised flow
    Channel type: Pipe, open channel, natural stream

    Cable: 15 metre, 9 way vented <> compatible
    Cable Options: User specified up to 50 metres

    Electrical specifications

    Power Source: External Battery 12V DC
    Power Usage: 11.5V to 15V DC, 50µA standby, 200mA active, 90mA communications
    Control: 1 x CMOS output trigger – water sampler
    Communication: 1 x RS232C Baud rates: 300/1200/2400/4800/9600/19200/38400
    SDI-12: SDI-12V 1.3 recorder (1200 baud smart instrument channel)

    Integrated logger specifications

    Storage memory: Low power CMOS RAM 512k standard
    Time clock: Crystal regulated, +/- 10 seconds/month
    Scan rates: Programmable from 5 seconds to 5 minutes
    Log intervals: Programmable from 5 seconds to 24 hours
    CPU: 80C552 microcontroller, 14.7456 MHz

  • Ordering Information

    The full product consists of the following models: 6526J5, 6526M-2, 6603D-SDI, 6603DT and 6308B-AUE

    Model Description
    6526J-21 2m depth Starflow System
    6526J-21-S Special cable length (up to 50m) 2m depth Starflow System
    6526J-51 5m depth Starflow System
    6526J-51-S Special cable length (up to 50m) 5m depth Starflow System

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    • Documents

    • Q: What information do you get from Starflow if you issue GET command?
      A: Please see Engineering Memo for more info Using GET command with Starflow