Do not seven: the lighting distribution box (board) protection line is not in place, the line diameter does not match
Impact: The protection wires of the lighting distribution box (board) are not arranged from the terminals, but are connected in series by the cabinet frame, the wire diameter is not set as required, and the device with the super-safe voltage of the distribution box door is not provided with the protective ground wire. It is easy to cause a safety accident.
Solution: According to the requirements of the specification, within the lighting distribution box (board), a protective ground wire busbar shall be provided, and the protective earth wire shall be connected on the busbar.
The cross-sectional area of the protective earthing wire shall not be less than the cross-sectional area from the power source to the maximum lead of the electrical appliance; and it shall also be selected in accordance with relevant regulations. The grounding on the distribution box (board) should be secure and must have a loosening device.
An openable door with more than 50V electrical equipment, the movable panel should be reliably connected to a well-grounded metal frame with a bare copper cord. The cross-sectional area of the bare copper cord should also be selected as required. The metal box and the box body with a wall thickness of less than 2.5 mm should not be used as a span of the pipeline. Grounding wire and protective earthing wire crimping point of the electrical appliance.
Do not eight: lighting distribution box (board) using wood materials without flame retardant treatment
Impact: If the lighting distribution box (board) is used in a damp and dusty place, it is easy to cause mildew and electric leakage. In addition, the wooden box (board) is not subject to flame retardant treatment, which is easy to cause fire, which is an unsafe hidden danger.
Measures: In order to ensure safe use, the lighting distribution box (board) should not be made of combustible materials. Even in dry and dust-free locations, the wooden distribution boxes (boards) used should be flame-retarded before they can be used.
Do not ten: lighting distribution box (board) did not check
Impact: The lighting distribution box (board) has not been inspected, and it is often found after installation: its two-layer board has no special grounding bolts, the protective grounding wire has a small cross section, and the electric-powered openable door does not use bare copper cord. Reliable connection with metal frame, wire and appliance connection is not strong, there is anti-circle phenomenon, screw mother does not need galvanized parts, wire diameter does not meet the requirements, there is no color mark, no card cabinet and electrical circuit diagram, appliance layout, interval Unreasonable, no N and PE terminal strips are set. Modifying the delay period also affects quality. ,
Program: Improve according to impact.