一般較有規模的企業都會需要有空調監控系統的需求，因此經常都會使用SCADA (資料採集與監視系統, Supervisory Control And Data Acquisition ) 來做為監控平台。而SCADA最常見的架構方式就是在現場端使用PLC ( Programmable Logic Controller ) 對周邊的元件做遠端控制、狀態監控及數據收集，PLC再統一傳輸資料到上層的PC主系統，並藉由PC來做資料儲存的功能。而以傳統的方式而言，當中所使用到的傳輸連接方式大部分都會以實體線路為主，因此不管是在建置或維護上都必須花費很多時間、人力及物料成本。
本研究完成無線通訊之空調監控系統之設計與實現，在感測節點的位置採用LoRa、Zigbee及Wi-Fi無線通訊模組安裝至MCU (Micro Control Unit)，且使用分散式架構，不僅可以達到縮短建置的時間，還可降低維修及除錯難度，並依照不同遠近的場域使用各自合適的無線通訊方式，再集中收集至Raspberry Pi，而此Raspberry Pi即同時安裝了LoRa及Zigbee無線通訊模組，再加上原先具備的Wi-Fi功能，可將其視為一個提供多種無線通訊介面的閘道器 (Gateway)。而以資訊安全的層面來看，當駭客想勒索一間製造商公司，則可針對其廠務監控系統做攻擊，使其癱瘓，工廠的生產一定會大受影響，因此以監控系統而言其資訊安全是必須受到重視的。為此本研究也在資料傳輸的過程中進行加密，來防止機敏資料被攔截或被獲取控制權。一般所使用的SCADA都是屬於商業軟體居多，基於低成本考量，本架構採用Node-RED開發平台建構出一個免費的使用者介面，來當作即時監看、歷史查詢及檔案管理的一個操作系統，因其屬於開源的開發平台，故以整體開發靈活度而言可以提供更廣泛的應用。

A lot of companies that use the Supervisory Control and Data Acquisition (SCADA), and it can help companies to monitor and manage the air-condition system. The most common structure of SCADA is to use PLC (Programmable Logic Controller) on the field side to remote control, status monitoring and data collection of peripheral components. In the traditional way, most of the transmission and connection methods used are mainly based on physical lines. There is a lot of cost to build or maintain.
First of all, this research focuses on the implementation of the wireless air-conditioning monitoring system, which uses LoRa, Zigbee and Wi-Fi wireless communication modules, and Micro Control Units (MCU) are also installed on these modules. The using of a decentralized architecture includes not only shorten the construction time, but also reduces the difficulty of maintenance and debugging.
Furthermore, according to distances and fields, the companies use the appropriate wireless communication systems to collect the data on Raspberry Pi, which is installed with LoRa and Zigbee wireless communication modules, and already Built-in function Wi-Fi. It can be regarded as a gateway that provides multiple wireless communication interfaces. This system can protect a company’s privacy information. For example, the company can use this system to prevent a hacker attack its factory monitoring system to paralyses it. Therefore, this research also encrypts the information in the process of transmission to prevent sensitive data from being intercepted or gaining control.
In conclusion, this study provides many organizations and companies with an alternative system on the Node-RED free development platform, which can be applied in the future with low cost and security.

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