A measuring box is a comprehensive set of measuring instruments and auxiliary equipment necessary for measuring electrical energy, including energy meters, measuring voltage and current transformers and their secondary circuits, energy measuring screens, cabinets, boxes, etc. The measuring box can be installed in a suspended or floor standing manner. To ensure installation quality, the suspended box must be fixed with built-in expansion bolts, and the bolt size must meet the requirements of safety and firmness as well as outdoor installation conditions.