An Inexpensive, Low-Maintenance, Precision Amplifier, Dissolved Oxygen Sensor, and Miniature Data Logger System Designed for Long-Term Deployment in Riverine Systems

（一種廉價的，低維護，精密放大器，溶解氧傳感器，微型和數(shù)據(jù)記錄系統(tǒng)，設計用于長期部署在河流系統(tǒng)。）

文獻：

DOI:

10.1577/T08-011.1

• Received: 16 Jan 2008
• Accepted: 22 Oct 2009
• Published online: 09 Jan 2011

• Abstract

  The dissolved oxygen (DO) concentration is a dynamic water quality variable that is critical to fisheries. To obtain simultaneous DO data at 15-min intervals over long periods (i.e., months) at a number of points along a river, a simple, inexpensive (<US$40) differential voltage amplifier circuit was developed to provide an interface between a galvanic DO probe and a miniature data logger. The circuit is designed around precision, micropower, single-voltage supply operational amplifiers and consumes less than 3 W while isolating and amplifying the output of a galvanic DO probe. The circuit is efficient and rapid enough to be powered by the data logger's 2.5-V, 1-mA, 18-ms-read sensor trigger signal. The complete unit, including the enclosure and floats, was constructed for less than $700. Fourteen were deployed in the upper portion of the St. Johns River, Florida, over an 18-month period. The units remained continuously deployed for 4- to 6-month periods 82% of the time, and 93% of the collected data passed quality assurance tests.

  摘要
  溶解氧（DO）濃度是一個動態(tài)的水質變量，對漁業(yè)而言非常關鍵。按照15分鐘的時間間隔，在某一數(shù)量的點，沿河流布置，長周期（幾個月）運行。一種簡單，廉價的差動電壓放大器電路的開發(fā)，提供一個DO探頭和一個微型的數(shù)據(jù)之間的接口同時進行數(shù)據(jù)記錄儀。該電路的設計是圍繞精密，微功耗，單電源運算放大器，功耗小于3瓦，而隔離和放大電流的輸出DO探頭。電路是有效的，并足夠迅速由數(shù)據(jù)記錄器獲得2.5-V，1-毫安，18毫秒的讀傳感器的觸發(fā)信號。完整的單元，包括外殼，構建了不到700 $。部署在圣約翰河，佛羅里達州的上部，在18個月內。單位仍然連續(xù)部署4-至6個月的時間段的82％的時間，并通過質量保證測試所收集的數(shù)據(jù)的93％。