FFZ-01Z Digital Water Surface Evaporation Station

1. Overview

The FFZ-01Z digital water surface evaporation station is manufactured in accordance with the "Water Surface Evaporation Observation Specification" SD265-88 issued by the Ministry of Water Resources and Electric Power of the People's Republic of China and the relevant requirements of the "Ground Meteorological Observation Specification" of the China Meteorological Administration, 2003 edition, for automatic observation of the water surface evaporation process.
The definition of "Digital Water Surface Evaporation Station" refers to an evaporation station where all components, including evaporation gauges, rain gauges, overflow buckets, data collection and control processes, and water replenishment processes, are fully digitalized for the observation of water surface evaporation volume.
The FFZ-01Z evaporation station features a resolution of 0.1mm for both the evaporation gauge and the rain gauge, with a flow overflow resolution of 0.025mm. It meets the high-grade requirements of relevant national standards. The precipitation and evaporation data tables comply with the requirements for data integration and storage. Suitable for equipping various types of water surface evaporation observation stations, it replaces laborious and complex manual observations, enabling automatic observation and recording of water surface evaporation.
The FFZ-01Z type evaporation station can be connected with a GPRS data transmission device to form a remote monitoring station.
Our equipment is intended for use during non-freezing periods only.
The evaporimeter, rain gauge, and overflow buckets in our equipment should be maintained regularly according to the instructions provided in the product manual.
2. Working Principle
This evaporation station system utilizes evaporation gauges, rainfall gauges, and overflow buckets as basic observation tools. It automatically collects, processes, and displays information on evaporation, precipitation, and overflow processes, as well as controls the refilling of evaporation and overflow buckets, and drainage. The collector connects to the host computer system and a data transmission communication unit (RTU) via RS485/232 communication interfaces. With the accompanying application software, it enables remote monitoring of water surface evaporation process information and data compilation for storage.
The water level in the evaporation pan of the operating evaporation station should be maintained at the water level marking line. On days without precipitation, the collector automatically collects the water level change inside the evaporation pan to calculate the evaporation amount. Whenever the water level inside the evaporation pan drops to the agreed value (10mm below the water level marking line), the collector controls the operation of the补水泵B3 at the boundary moment of the observation day (hydrological boundary day at 8:00, meteorological boundary day at 20:00) to automatically replenish water to the evaporation pan and water ring, restoring the water level in the pan to the height of the water level marking line. Then, with the height after replenishment as the starting point, the evaporation amount for the next period is measured.
On days with precipitation, when the water level in the evaporation bucket rises to the agreed value (10 mm above the water level marker), the collector drives overflow pump B1 to operate, allowing water from the evaporation bucket to flow into the overflow bucket. Once the water level in the overflow bucket reaches the agreed value, the overflow process ends. After the collector collects and calculates the overflow volume data, it starts the overflow bucket drainage pump B2 to discharge the water from the overflow bucket to the agreed base water level.
According to the "Specification for Surface Evaporation Observation" and the "Specification for Ground Meteorological Observation" of the National Meteorological Administration, the formula for calculating evaporation is:
Evaporation amount = (Evaporation drum water level measurement - Evaporation drum water level starting value) + Precipitation - Overflow amount
The above expression can be simplified to: QF = (Wt - W0) + Qj - Qy
In the formula: QF: indicates the water surface evaporation amount, unit: mm
Wt: Represents the evaporating pan water level at measurement time (t), unit: mm
W0: Represents the initial evaporation pan water level, unit: mm
The Wt and W0 values are automatically measured by the FFZ-01 digital water surface evaporation gauge.
Qj: Represents the precipitation during the measured period; the Qj value is provided by the JFZ-01 digital rain gauge, unit: mm
Qy: Indicates the overflow flow rate during the measured period, with the Qy value automatically measured by the overflow bucket; Unit: mm