Solar
Solar ACDB vs DCDB: What Is the Difference?
An ACDB serves the alternating-current side of a solar installation; a DCDB serves the direct-current side. Their ratings and switching devices are different.
Where each board is installed
The typical path is PV strings → DCDB or inverter-integrated DC protection → inverter → ACDB → main distribution or grid connection. The exact arrangement depends on inverter design and the approved project diagram.
Compare the protection
DC circuits require equipment suitable for sustained DC arcs and the array voltage. AC circuits require devices suited to AC voltage, frequency and prospective fault current. Neither board replaces inverter anti-islanding functions or all upstream protection.
Selection checklist
For a DCDB, check cold-weather string voltage, string current and MPPT routing. For an ACDB, check inverter output current, phases, feeder size, fault level, isolation and surge coordination. Never substitute an AC breaker for a DC-rated device.
Discuss your project with GEESYS
Share your load details, site conditions and single-line diagram for a project-specific recommendation.
Explore related products | Contact GEESYSFurther reading: SMA string-combiner documentation. Use the documentation for the equipment installed on your project.
Related technical guides
- How to Select the Right Solar DCDB for Your Solar Plant
- What Is a Solar Combiner Box? Complete Guide
- Solar String Combiner Box: Working, Features and Applications
- What Is a Solar AC Combiner Box?