With man’s increasing need to consume water, need to measure water in open channels has also increased. Open channels are those natural and man-made structures through which water flows with a free surface. For open channels a number of different and varied methods have been developed to measure the flow of water. Modern mechanical and electronic flow meters have made the continuous measurement of open channel flows possible. 

Pune Techtrol offers solutions for measuring “Loss of Head”  (differential level) between upstream and downstream of the filter screen in open channels of WTP’s / ETP’s, filtration stations, water management systems, etc.

Techtrol’s ultrasonic loss of head level system – LHUS is widely used in water canals, water treatment plants, sewage pumping and filter stations. It consists of a pair of ultrasonic transmitters and a differential level controller. The transmitters are installed on either side of the filter screen to translate the level change into an analog signal by using time of flight principle. The relative difference between the two signals from upstream and downstream is processed by the evaluation unit and displayed as “Loss-of-Head” digitally.

Salient Features

• Ultrasonic, Non-contact measurement.
• Easy to install and operate.
• Minimal maintenance due to non-moving parts
• Displays differential level
• Easy calibration through keypad
• Option of Re transmission 4-20 mA for DCS/PLC
• Two potential free change-over relays can be configured as Single Point or Pump Control/Screen Control Alarm for either Low Head, High Head or Difference.

System Operation

The system (Fig 1) consists of two Ultrasonic Transmitters (Ultratrol), which consist of ultrasonic transducer integral with microcontroller based electronics housed in an enclosure. Ultrasonic pulses emitted from the transducer to the target are reflected back and sensed by the electronics to provide 4-20mA current output. The two Ultrasonic Transmitters are mounted on the upstream and downstream side of the bar screen placed in an open channel. These transmitters are connected to Differential Level Controller (TDLC) with relay set at a predefined value. The level difference between upstream and downstream side is measured by the TDLC to actuate a preset relay.

TDLC can also be provided with 4-20mA (re- transmission) to DCS / PLC Screen Panel for further control and automation.

Applications:

“Techtrol” Loss of head ultrasonic system-LHUS is suitable for use in Waste Water, Sewage, Effluent Treatment Plants, Open Channel, and Water filtration plant –filter bed level.