摘要：Electro-mechanical tipping bucket runoff-meter was designed and developed to measure surface runoff water using locally-sourced components. The instrument consists of metallic-fabricated runoff plot area of 2 m2, depth 0.25 m and metal gauge of 3mm. The tipping operationwas initiated by arranging the sensitive electro-mechanical components such digital micro-switch (SW1,SW2, SW3 and SW4), pair of open/close circuit breakers (No,Nc), electronic speed gear and circular rotating disc to a pair of twins buckets of runoff volume 0.141 liter capacity per bucket which corresponds to 0.25 mm runoff depth. The whole arrangement was powered by a 12V by 75 AH battery and the tipping processes was being recorded by the electro-mechanical data logger. The instrument has a measuring accuracy of ±0.001 liter per tip. It was calibrated to measure minimum and maximum runoff volume from 0.14l to 200 liters, these values correspond to 0.25 mm and 800 mm runoff depths respectively. Therefore, precise results obtained using the instrument could be used to establish strong database for measuring and storing accurate surface runoff data which in turn could be applied for hydrological modeling for sustainable water resources management and design of hydraulic structures.
