Attach busbars to the main (primary) MCCB (R, Y, B, & Neutral for 3-phase). Link branch circuit wires to respective outgoing MCCBs. Connect the grounding busbar to the panel and the. Drawing on international standards, long-term field data, and enclosure-level design experience, we clarify best practices for copper busbar joints —helping designers, engineers, and project managers make safer and more cost-effective decisions. Many engineers assume that increasing the busbar. The GRL busbar system makes distribution cabinet installation fast, flexible, and neat. Follow these instructions during the installation process: Start the installation by connecting the switchboard.