There are many methods for testing boxes, but the commonly used tools are vernier calipers, tape measures, and levels. In-box inspection requirements: the inspector must inspect the materials in the box one by one according to the design drawings, and check whether there is a small amount or leakage of the processed parts. The following issues should be paid attention to when checking the cabinet.

1. The external dimension deviation of the LED box is within 0.5mm, and the diagonal deviation is within 1mm.

2. Check whether the burr is cleared, whether the acute angle is blunt, whether it is scratched, whether the hand is allowed to have thorns.

3. Each nut and nut column must be tooth-returned to ensure the smooth tightening of the threads.

4. Check whether the assembly of the LED machine housing meets the requirements of the drawings. All components (locks, hinges, etc.) should use existing standard components to ensure the mechanical strength and sealing performance during assembly.

5. The welding of each welding part of the box body must be firm, free of false welding, missing welding, etc., the solder joints should be flat, the solder joints should be scraped, the process requirements are strict and the specifications are required. The surface of the welding seam should be polished and sealed, waterproof, smooth, and without sharp angles.