At times, depending on the difficulty of flow monitoring site applications or conditions, as well as in overflow monitoring or billing scenarios, more than one level measurement is desired to guarantee accuracy. That’s where the Hach Redundant-Level Monitoring System comes into play. This system combines a Hach FL900 Series Flow Logger with AV9000 Analyzer Module, a Sigma Submerged AV Sensor, and a Hach US9003 In-Pipe Ultrasonic Sensor to create a highly accurate level monitoring solution. In this configuration, level is captured by both a pressure transducer in the Sub AV sensor and with ultrasonic technology in the in-pipe sensor, dramatically limiting your risk of missing data.

Hach FL900 Series Flow Logger

  • Extremely rugged to handle harsh environments
  • Four sensor ports for any Hach sensor
  • Rain Gauge port
  • COM port for direct meter communication or access to MODBUS
  • Cellular wireless modem for real-time data access
    • Carriers available include Verizon, AT&T, Sprint & Rogers

Sigma Submerged AV Sensor

  • Robust, 1 MHz Acoustic Doppler flow sensor with improved resistance to sensor fouling through either oil-filled or non-oil-filled options
  • Uses a pressure transducer to calculate flow level
  • Incorporates advanced technologies to ensure accuracy, including automatically correcting for temperature effects on measurements.
  • Pairs with Hach AV9000 Analyzer Module to provide “cleaner,” more precise data
    • Advanced signal processing and filtering options
    • Accounts for water temperature swings and salinity concentrations

Hach US9003 In-Pipe Ultrasonic Sensor

  • Eliminates inherent ultrasonic deadband and provide accurate measurements in near-full pipe conditions
    • Transducer is mounted parallel to the flow surface within an engineered enclosure that contains a 45° reflector
  • Non-contact monitoring technology greatly reduces chance of sensor fouling
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