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　　用于消防排煙系統(tǒng)中，當(dāng)有火警發(fā)生時(shí)可通過(guò)該按鈕來(lái)緊急開(kāi)窗排煙。緊急按鈕線路在遇到開(kāi)路或者短路故障，排煙窗會(huì)立即自動(dòng)開(kāi)啟，保障了消防排煙窗系統(tǒng)的可靠性。

Used insmoke exhaust system, to open window and exhaust smoke by manual emergencybutton when firing, smoking window will open automatically when there is somewrong with open circuit or short circuit of emergency button line, Guaranteethe high performance of smoke exhaust system.