3 Phase Busbar Trunking

Three-phase busbar systems are divided into three-phase four-wire busways and three-phase five-wire busways. The former is composed of three phase conductors (A, B, C) and one neutral conductor (N), without an independent protective earth (PE) conductor, where the PE function is achieved through the enclosure. The cross-sectional area of the neutral conductor is typically 50%-100% of that of the phase conductors: for balanced three-phase load systems like motor groups, the neutral only carries unbalanced currents, allowing its cross-section to be 50% of the phase conductors; if single-phase loads account for more than 30%, the neutral cross-section should be increased to 100% of the phase conductors to avoid overload. The latter adds an independent protective earth (PE) conductor based on the former, with the PE busbar insulated from the enclosure and directly connected to the metal casings of equipment. The independent PE busbar can quickly drain leakage currents, making it suitable for scenarios with strict requirements for electric shock protection.

1.three-phase four-wire busways: 

Due to the absence of an independent grounding busbar, this type of busway is more suitable for scenarios with low protection requirements, including temporary power supply projects such as tower cranes and lighting in construction sites, as well as applications where basic safety requirements can be satisfied through enclosure grounding (e.g., refrigeration rooms in shopping malls, ventilation equipment in underground garages). This helps achieve cost reduction and efficiency improvement.

2.three-phase five-wire busways:

The separation of the N busbar and PE busbar can reduce harmonic interference from the neutral conductor to the PE, ensuring the stability and precision of equipment operation, making it suitable for powering precision electronic devices.

Hot Tags: 3 phase busbar trunking, China 3 phase busbar trunking manufacturers, suppliers, 3 Phase Sandwich Busduct, Busway Flange, Compact Busduct, Rising Mains Busway, Sandwich Busway, Segregated Bus Duct