Split-bus electrical panels were commonly installed in homes built from the 1950s through the early 1980s. These panels have no single main breaker, instead requiring up to six individual breakers to be turned off to disconnect all power. The National Electrical Code eliminated the "six-throw rule" that allowed this design in 1981, and split-bus panels have been considered obsolete ever since. If your Aiken, SC home has a split-bus panel, upgrading to a modern single main breaker panel improves safety, meets current code standards, and resolves insurance concerns.
Why Split-Bus Panels Need Replacement
While split-bus panels are not defective in the same way that Federal Pacific or Zinsco panels are, they present significant concerns due to their design and age.
No Single Emergency Disconnect
In an emergency such as a fire, electrical shock, or flooding, you need to shut off all power immediately. With a split-bus panel, you must identify and flip up to six separate breakers in the upper section. In a dark, smoky, or stressful situation, this delay can be dangerous. A modern panel provides a single main breaker that disconnects everything with one motion.
Does Not Meet Current NEC Code
The NEC has required a single service disconnect since 1981. While existing split-bus panels are grandfathered, they do not meet current safety standards. Any significant modification, repair, or upgrade to the panel may trigger a requirement to bring the entire installation into compliance with current code.
Age-Related Deterioration
Every split-bus panel still in service is at least 45 years old. Decades of thermal cycling have loosened connections, worn breaker contacts, and degraded wire insulation. The internal components are well past their intended service life, and the risk of failure increases with each passing year.
Capacity Limitations
Most split-bus panels are rated for 100 or 150 amps, which was adequate for 1970s electrical demands. Modern homes with central air conditioning, electric water heaters, home offices, and EV chargers typically need 200-amp service. Running an undersized panel near its capacity accelerates wear on every component.
How to Identify a Split-Bus Panel
The easiest way to identify a split-bus panel is to open the panel door and look at the breaker layout.
- No main breaker: If there is no single large breaker at the top of the panel labeled as the "main," you likely have a split-bus panel or a main lug panel.
- Two sections of breakers: Split-bus panels have an upper section with large double-pole breakers (typically up to six) and a lower section with standard branch circuit breakers. One of the upper breakers feeds the lower section.
- Age of the home: If your home was built between the 1950s and early 1980s and has never had a panel replacement, there is a good chance it has a split-bus panel.
If you are unsure about your panel type, we can identify it during a free inspection. For more details about split-bus panels, read our blog post: Split-Bus Panels: What They Are and Why They Need to Go.
Our Replacement Process
Replacing a split-bus panel is a straightforward process that we handle from start to finish.
Assessment and Load Calculation
We evaluate your current panel, identify all existing circuits, check wire sizes, and perform a load calculation to determine the right panel size for your home. Most split-bus panel replacements include an upgrade from 100-amp to 200-amp service.
Flat-Rate Quote
You receive a written quote that covers everything: new panel, breakers, labor, materials, permits, and any required service entrance upgrades. No hidden costs.
Permitting and Coordination
We handle all permits with Aiken County and coordinate with your utility provider for the temporary power disconnect. If a service entrance upgrade is needed to support 200-amp service, we include that in the scope of work.
Installation
We remove the old split-bus panel and install a new 200-amp main breaker panel with all new breakers. Every circuit is reconnected, the grounding system is verified and updated, and all circuits are clearly labeled. Most jobs are completed in one day.
Inspection and Approval
The county electrical inspector examines the completed work. Once approved, the utility reconnects power. You receive all documentation including permits, inspection records, and warranty information.
Benefits of Upgrading
Replacing your split-bus panel delivers immediate, tangible benefits for your home.
- Single main breaker: One switch to shut off all power in your home. Faster, safer, and simpler in any situation.
- 200-amp capacity: Enough power for central air, electric appliances, EV chargers, and future additions.
- Modern safety features: Ability to add AFCI and GFCI breakers as required by current code.
- Insurance compliance: Eliminates a common insurance concern and may reduce your premiums.
- Increased home value: A modern, code-compliant panel is an asset during resale.
- Properly labeled circuits: Clear identification of every circuit for easy maintenance and troubleshooting.
Ready to Replace Your Split-Bus Panel?
Serving Aiken, SC and surrounding communities including North Augusta, Graniteville, New Ellenton, Jackson, and Clearwater. Get your flat-rate quote today.