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2. Surge tank level monitoring

The main function of a surge tank is to control pressure variations due to rapid changes in the velocity of the water. When the power turbine is running at a steady load, there are no surges in the flow of water since the quantity of water flowing through the conduit is sufficient to meet the turbine’s requirements. When the turbine load decreases, a governor closes the gates of the turbine to reduce water supply. The water is routed for storage in the surge tank—an action that prevents the conduit from bursting. When the turbine load increases, additional water is drawn from the surge tank to meet the increased demand. A surge tank’s internal diameter may range from a few feet to several dozen feet. The tank relies on a level sensor to determine whether or not water stored in the tank should be removed.



  • Accurate, continuous measurement
  • Unaffected by airflow (wind)
  • No protective devices required – stilling wells, baffle plates, etc. (flow rate)
  • Flexible antenna & mounting configurations
  • No calibration, no moving parts, reliability
  • PnP configuration, low/easy maintenance
  • Meets FCC, ESTI & Industry Canada requirements for open-air/tank installation