求翻译：使用前，先将箱体注满水，箱体左侧三个水口分别是最上面是“注水口”，中间是“溢水口”，最下面是“排水口”。面板上的各控制开关应处于非工作状态。是什么意思？

Before use, first tank filled with water, box above three points are the most on the left is "water", the middle is "overflow", the bottom is "drains". The control switch on the Panel should be in a non-working state.