If it is not the zero-adjustment mechanism will be damaged .

若 放置不 正确，将破坏 调 零机构。

Use a slotted screwdriver to turn the zero-adjustment screw .

采用一字螺丝刀旋转 调 零螺钉。

Turn the external zero-adjustment screw in the desired direction .

向所需方向扭转外部 调 零螺钉。