Main panels serve as the central power intake, while distribution panels split and manage electricity to specific circuits or zones within a building.

Main Distribution Boxes (Main Panels)

A main panel, also called a main distribution box, is the primary point where electricity from the utility enters a building. It houses the main breaker, which controls the overall power supply and provides full-system protection against overloads and short circuits. Main panels handle higher voltages and currents, typically ranging from 100A to 4000A, and are usually installed near the utility source. They distribute power to branch circuits or downstream distribution panels, ensuring centralized control and safety for the entire electrical system . Key components of a main panel include:

• Incoming terminals connecting to the utility supply
• Main circuit breaker for overall system shutdown
• Branch breakers for individual circuits
• Optional surge protection and metering devices

Distribution Panels

A distribution panel (or distribution board) acts as an intermediary hub that receives power from the main panel and divides it into smaller circuits for specific areas, floors, or equipment. These panels are ideal for multi-zone or large buildings, providing localized control, load balancing, and energy monitoring. Distribution panels typically operate at lower capacities (50A–800A) and are installed inside buildings for convenient access . Key features of distribution panels include:

• Busbars for efficient power distribution
• Multiple outgoing breakers feeding downstream circuits or equipment
• Optional integration of surge protection, metering, and monitoring systems
• Modular enclosures with IP-rated sealing for harsh environments

Panelboards vs Distribution Panels

While the terms are sometimes used interchangeably, panelboards are generally compact assemblies designed to control and protect individual branch circuits, often in residential or light commercial settings. Distribution panels, on the other hand, serve as a central hub for routing power to multiple panelboards or large equipment, making them more common in industrial or multi-zone applications .

Summary of Differences

Understanding the roles of main panels and distribution panels is essential for designing safe, efficient, and maintainable electrical systems in any building type .