Connection of Busbars to Cables and Other Distribution Equipment in Switchgear

Busbars serve as the foundation of all power distribution equipment and are integral to assembled distribution facilities such as Switchgear and substations. Functioning as a central hub within a circuit, they efficiently and reliably aggregate and distribute electrical energy within a localized system. However, busbars cannot operate independently. To transmit and distribute electricity effectively, additional components are essential. Since loads may be distributed across various locations, often at considerable distances, cables—capable of traversing conduits, cable trays, and spatial obstacles—play a critical role in delivering electricity to where it is needed. Thus, the connection between busbars and cables becomes indispensable. What are the available connection methods?

The first is bolted connection, the most mainstream and classical method. This involves crimping a cable terminal to the end of the conductor and securing it to a pre-drilled hole or connection surface on the busbar using fasteners such as bolts, nuts, flat washers, and spring washers. During bolted connection, it is essential to use a torque wrench tightened to the standard torque value. Insufficient torque may increase contact resistance, leading to overheating, while excessive torque can damage threads or the busbar itself.

The second method is plug-in connection, typically used in draw-out-type switchgear. The busbar system is fixed within the frame of the switchgear, while the circuit breaker and its socket are installed on a draw-out tray. Inserting the tray engages the dynamic and static contacts precisely, while withdrawing it disconnects them.

The third method is crimping connection, also known as conductor pre-treatment. This is not a direct connection to the busbar but a critical preparatory step for bolted connections. It involves using hydraulic or mechanical crimping pliers to permanently compress and secure a cable terminal to the conductor core.

Within switchgear, busbars must also connect to other power distribution components, such as main incoming circuit breakers, feeder breakers, disconnect switches, and load switches. The connection methods between busbars and these components are largely similar to those between busbars and cables, with one key distinction: connections between busbars and components are generally detachable, whereas connections between busbars and cables are typically permanent.

The above elaborates on the methods of busbar connection.

As a supplier of assembled equipment and transformers, we possess not only extensive expertise and experience in busbar connection methods but also demonstrate proficiency throughout the entire process of equipment design and manufacturing. We are committed to providing high-quality products and excellent service. Welcome to consult with Hangbian Electric Technology Co., Ltd.