環境試驗對電纜線負載時表面溫度影響之研究

Abstract

本研究的目的在探討電纜線及電線經過四種的標準環境試驗後，再以紅外線熱影像觀察其在工研院所研發的電纜發熱走火模擬機上，通以各種不同電流負載下其表面溫度的變化，進而探討其相關的安全影響。實驗樣品為太平洋電纜線600V XLPE 及600V PVC電纜線為二種；使用負載為以安全電流值之80%、100%及150%和200%；而環境試驗項目包括有高溫、發熱、溼熱、鹽霧及嚴酷度試驗等四種。實驗結果發現高溫環境對電線外觀影響最大；鹽霧環境則會導致接頭通電後溫度明顯上升；而溼熱及嚴酷度亦是影響表面溫度過載的重要影響因素，且彼此相互影響。因此本研究結論是環境及使用過載是會造成電纜線表面溫度上升近而是有火災風險之虞，兩者在某些部份匹配下會有相互作用。最後本研究建議：1.定期的檢查是必要的預防措施，在含鹽或高溫地區，電纜線接點的位置是為檢查重點；而高溼度地區則需要檢查電纜線其他位置。2.防止電過載使用亦是避免電線火災的重要措施。

This thesis is aimed to investigate the cable surface temperature variations as the functions of the current load and four different environmental factors. The tests are carried out on a cable fire simulating equipment designed by the Center For Environmental Safety and Health Technology Development Industrial Technology Research Institute. An IR Thermography is used to monitor the corresponding surface temperatures. The test samples are 600V XLPE and PVC, respectively. The loads used are 80, 100, 150 and 200% of assigned safe current values. Environmental items include high temperature, temperature and humidity, salt spray and reliability tests. From the test results, it is found that high temperature environment affects the surface pattern greatly; salty spray one leads the connector temperature to raise as it is subjected load, and temperature and humidity as well as reliability environmental tests cause the cable overloaded. These factors are couple together and influenced each other. As a consequence, this thesis concludes that the environments and overload are the main reasons to cause the temperature rise of cable surface, subsequently, the potential risk of cable fire. Accordingly, this study recommends: (1) regular inspection be needed, especially on the connected area with screw of cable, in addition to that the other location of cable when subjected to high humidity environment, and (2) over loading of cable be avoided.