Are guards provided over foot activated control pedals to prevent inadvertent activation? 对于可被脚打开的控制开关,是否安装有护罩,以防止脚无意中开启设备?
The rheostat is operated by rotating the control knob, separating it from the push-pull action of the main lighting switch. 可变电阻器由旋转的控制手柄操纵,与灯光总开关的推一拉的操纵是分开的。