How To Use A Power Distribution Cabinet Correctly

The Powbinet unit in industrial and commercial sites performs the dual functions of power distribution and line protection, and its proper use is directly related to the stability of the power supply system. Before commissioning, the nameplate parameters must be checked for compatibility with the actual load, and a 20-30% margin should be allowed in the rated current. The functional zones of incoming line cabinets, metering cabinets, and outgoing line cabinets should be clearly defined, and identification plates should clearly indicate the circuit name and load capacity.

The tripping curve of the circuit breaker needs to be adjusted according to the load characteristics. Lighting circuits are suitable for type C tripping characteristics, while motor circuits should use type D to withstand starting current surges. The operating current of the residual current device (RCD) should be set at 30mA for personal protection and 300mA for fire protection. The bolt torque at busbar connections must meet the specified value; dedicated terminals must be used for copper-aluminum transitions, and conductive paste should be applied to the contact surfaces to reduce contact resistance.

Temperature monitoring during operation is crucial. Infrared thermometers should be used monthly to check the temperature of the busbars and circuit breaker terminals; a temperature exceeding 40°C above the ambient temperature is considered abnormal. Ventilation vents inside the cabinet should be kept clear, and the top cooling fan should be operating normally. The switching frequency of the capacitor compensation cabinet should be controlled within 8 times per hour, as frequent operation will shorten the life of the capacitors.