Fully automatic digital evaporation station

Surface evaporation is an important link in the water cycle and a significant topic in hydrological research. It is the main part of water loss in reservoirs, lakes, and other bodies of water, and is also the basic reference material for studying land surface evaporation. Water surface evaporation data is required in water resource assessment, hydrological model determination, water conservancy and hydropower engineering, and planning, design, and management of industrial and mining enterprises with large water consumption.

Water surface evaporation, as a characterization of evaporation capacity, is a necessary analysis content for water resource evaluation work. Generally, the water surface evaporation of the E601 type evaporator on the ground is used as the analysis basis. The use of the E601 ground evaporator in various parts of China dates back to the early 1960s and has accumulated more than 40 years of measured data. This not only provides important basis for previous national water resources surveys and evaluations, but also lays the foundation for the study of the long-term variation law of water surface evaporation.

system configuration

The MC-ZDF fully automatic digital evaporation station realizes automatic water level change measurement, automatic overflow calculation, automatic rainfall calculation, and automatic water replenishment on the basis of manual evaporation, thereby achieving automatic measurement of daily evaporation. GPRS wireless transmission is used in communication to send real-time monitoring data to the hydrological center, making it convenient for various units to access and view the data in a timely manner.

The evaporation station is an electromechanical integrated device composed of a digital water level gauge and an electrical control device with a single-chip computer as the core. It is used to detect the water level in the evaporation tank and control the action of the water replenishment pump. The evaporation gauge and the collector communicate through the internal RS-485 communication bus of the system.

The water level gauge consists of a static water tank, a photoelectric rotary encoder, a float, a balance weight, a circular steel wire rope hanging wheel fixed on the rotating shaft of the photoelectric rotary encoder, as well as a protective cover and base for the photoelectric rotary encoder.

The relay that controls the water pump and electric valve is inside the collector. When the relay is closed, the water pump or electric valve starts working, and when the relay is disconnected, it stops working.

The static water tank of the evaporation station is buried in the soil at the observation site. The lower part of the static water tank is connected to the evaporation tank through a connecting pipe, forming a connected structure with the evaporation tank to achieve synchronous changes in the water surface of both.

There is a horizontal bubble on the base of the water level gauge, which is used to observe and adjust the level of the water level gauge base during installation. The base of the water level gauge is connected to the static water tank as a whole with bolts.

The water level gauge has a circular stainless steel protective cover on the outside, and the lower part of the protective cover is fixed to the evaporator base with bolts.

The evaporation station has the function of recording evaporation data, which is stored every half hour and can record information for at least one year. The storage time can be increased according to requirements. Recording data has a power-off hold function. The evaporation data recording adopts a cyclic recording method, with new recorded data covering the earliest recorded data. The interval time for recording evaporation data can be manually set, with a default of recording data every minute. Each record data includes: the current recorded date and time, current water level, evaporation rate within three days, overflow rate, rainfall, as well as previous and previous evaporation rates, overflow rate, and rainfall.

The fully automatic evaporation station software can be installed on a personal computer to store, download real-time and historical data, and analyze the data transmitted by the evaporation station through the computer.

Real time data: instantaneous evaporation station data at the current computer time.

Historical data: The fully automatic evaporation station records data (collector clock) into the storage chip of the collector according to the set collection cycle.

After software installation, the software is set to default settings. Users can set software based on the hardware type of the data acquisition device they are using. Only when the software settings are consistent with the hardware can communication with the data acquisition device be normal.