ACDB (Alternating Current Distribution Box) and DCDB (Direct Current Distribution Box) are essential electrical safety panels in a solar system. The DCDB protects the inverter from the solar panel side, while the ACDB protects your home/grid from inverter faults. Together, they safeguard your solar investment from overcurrent and surges.

DCDB (Direct Current Distribution Box)

Installed between the solar panels and the inverter, the DCDB manages and protects the system before the electricity is converted.

• Function: Collects the DC power from solar strings and routes it to the inverter safely.

Key Components:

• DC Isolator/MCB: Used to manually or automatically disconnect the solar panels from the inverter during maintenance or emergencies.
• DC Surge Protection Device (SPD): Diverts sudden voltage spikes (like those from nearby lightning strikes) to the ground, protecting the sensitive inverter.
• DC Fuses: Provides string-level protection to prevent overcurrent.

ACDB (Alternating Current Distribution Box)

Installed between the solar inverter and the building's main electrical panel (or grid), the ACDB manages the converted AC electricity.

• Function: Ensures the safe distribution of usable AC power and synchronizes the system with the utility grid.
• Key Components:
• AC MCB / MCCB (Miniature/Molded Case Circuit Breaker): Trips and breaks the circuit if there is an overload or a short circuit from the inverter side.
• AC SPD: Provides an additional layer of surge protection for your home appliances and the grid connection.

For reliable and safe operation, both panels typically feature weather-resistant, dustproof, and waterproof casings (usually IP65-rated) so they can be installed outdoors on rooftops or walls.