INSTRUMENTATION
Reliable level readings from remote areas VEGA’s compact radar level measuring instruments provide energy-efficient measurement around the clock.
W
hile the Flanders Environment Agency (Vlaamse Milieumaatschappij; VMM) in Belgium can do little to change the volatility of the weather, it does play a decisive role in creating a water distribution strategy. The environmental agency measures and monitors water quantity and quality, as well as manages water systems and levies fees on water pollution and groundwater extraction. It also advises on environmental permits, supervises infrastructure planning and supplies drinking water. VMM relies on IoT (internet of things) solutions and adopts an integrated approach that focuses on limiting the risk of flood damage and achieving a high ecological status. VMM looks to ensure that no user or consumer in the complex system of water distribution is neglected. However, one can only monitor something that has been accurately measured. User-friendly, low-maintenance measuring equipment In the early days, ultrasonic sensing was used to measure the water level in non-navigable streams, canals and rivers. However, this measuring method had a major drawback, especially outdoors: the sound propagation time depended on the temperature, which resulted in considerable measurement errors due to temperature changes or solar radiation. Thick fog, wind and rain, as well as build-up of dirt, also influenced ultrasonic measurement. Even cobwebs caused inaccurate readings, as they gathered debris that interfered with the measuring signal and resulted in an increase in the blocking distance, or dead band. There were also ongoing maintenance problems. Radar sensors, by contrast, are not bothered by dirt, sunlight, fog, wind or rain. They also do not require mechanical protection from high floodwaters. For that reason, the decision was made over 15 years ago to change the sensor type; and since then, VMM has relied on radar technology from VEGA. They first worked with the radar level sensor VEGAPULS 61 with PVDF antenna for many years, then later with VEGAPULS WL 61. VMM especially appreciated the
50
JUL /AUG 2022
The exact location of each sensor is determined via a GPS module built into the data logger
