封闭外壳 meaning in Chinese

latch housing

Li - closed case and ventilation systems , do what good work environment
全封闭外壳与抽风系统，确何良好工作环境。
Test procedures for low - voltage ac power circuit protectors used in enclosures
封闭外壳内的低压交流电力线路保护器的试验程序
The totally - closed covering and the convulsion system , guaranteeing the good working conditions
全封闭外壳与抽风系统，确保良好工作环境。