H-flumes were developed to determine widely fluctuating flow rates, from very low to extremely high volumes. For example, seasonally variable flow rates or discharges due to severe precipitation events can be measured. Furthermore, H-flumes are also used for the detection of agricultural and industrial drainage processes. Provided that there is an open channel with free discharge at the outlet, they provide excellent accuracy even in contaminated water. A pre-set calming channel ensures a uniform distribution of the flow over the entire measuring width.

The H-Flumes are made of robust stainless steel. The water level is scanned without contact by means of an ultrasonic transducer or with capacitive sensors, which are installed in a V2A protective housing. When combined with UGT data loggers, the temperature and wind compensation of the ultrasonic transducers are performed in the data logger.

Measuring principle of the H-Flumes

An ultrasonic level sensor records the level in the flume at freely programmable time intervals and sends it to the data logger. To reduce environmental influences, this level value is internally compensated with the reference sensor value. The measured water level creates a defined cross-sectional area in the flume, which can be used to determine the flow rate when the water is flowing freely.

System components

• H-flume made of stainless steel
• Stainless steel calming channel
• Ultrasonic level sensor
• Ultrasonic reference sensor for drift compensation
• UGT data logger powered by a 6.5 Ah battery pack
• Data logger software

We supply H-flumes in three sizes to facilitate optimal alignment to the prevailing flow rate range: 

* Standart length approach channel 101 cm, custom lengths on request