Quality requirements for distribution cabinets

1. Main control project
The test and adjustment results of the cabinet (panel) must comply with the provisions of the construction specifications.
(2) The metal frames and basic steel sections of cabinets, screens, tables, boxes and trays must be reliably grounded (PE) or connected to zero (PEN). The grounding terminals of the openable doors equipped with electrical appliances and the frames should be connected with bare braided copper wires, and proper markings should be made.
(3) The signboards and frames on the board surface are complete, correct and clear.

(4) The insulation resistance values between lines and between lines and ground of the lines between cabinets (screens, tables) and boxes (panels), as well as for feeder lines, must be greater than 0.5 M Ω. The secondary circuit must be greater than 1 M Ω.

2 General project
(1) Cabinets, screens, tables, boxes and panels should be connected to the basic steel sections with galvanized bolts and all anti-loosening parts should be complete.
(2) The installation of distribution boxes (panels) shall comply with the following provisions:
The wiring inside the box panel is neat and there is no hinge phenomenon. The wires are tightly connected without damaging the core or breaking the strands. The cross-sectional areas of the wires pressed on both sides of the helix under the washer are equal. No more than two wires are connected on the same terminal, and the anti-inspection washers and other parts are complete. The circuit numbers are complete and the labels are correct.
The switches inside the box panel are flexible and reliable. For circuits with leakage protection, the operating current of the leakage protection device shall not exceed 30mA, and the operating time shall not exceed 0.1s.
The neutral wire (N) and protective grounding wire (PE) busbars are respectively set in the lighting box and the panel. The box (tray) is not made of flammable materials and has a complete coating.
The box position is accurate, the installation is firm, and all components are complete. The openings in the box are compatible with the diameter of the conduit pipe. The cover of the concealed assembly electrical box is tightly attached to the wall.
The vertical allowable deviation is 1.5‰, and the bottom edge is 1.5 meters above the ground.