Water Level Measuring Network Design and Implementation

The Yangtze River model was constructed to study the flood evolution in the middle and lower reaches of Yangtze River. To automatically measure and dynamically track the water level in the river model, water level meter was designed. An optical scale with 1um resolution was used as a position detection sensor; the optical scale output signals were processed and then were counted by the reversible counter T2 of the AT89S52 microcontroller. Water surface detection probe was designed based on the water with low electrical conductivity, and the probe was fixed on the sliding rule of the optical scale; a stepper motor was used to drive the probe slid up and down. When probe downward contacted the water surface, the counter value was read and the height of water level was displayed. A water level measuring network was constructed with a number of water level meters based on the MODBUS protocol and RS485. The water level measuring network has been used on the Yangtze River model and achieved the expected results.