Updating split level home
Note that the top six double pole breaker spaces are outlined with blue dotted lines and are numbered 1 through 6.
Note how the wires from breaker #2 travel down behind the six spaces and attach (trust me) to the bars for the bottom breakers highlighted in red.
To recap: In a typical split bus panel found in a residence there will be provision for “6” double pole breakers (or less)—one of which is the disconnect for all the breakers located below the 6 double pole breaker locations.
Wires will run from that one breaker and be connected directly to the bus bars for the other section of breakers.
The code allows for this type of panel as long as all the power can be shut-off in 6 throws or less—known as the “6-Throw Rule.” Inspectors and homeowners sometimes mistake these split-bus panels for sub-panels and incorrectly call for repairs to the way they are wired—or wonder where the main breaker is.
I don’t want to go into the differences between how service panels are wired differently from sub-panels, but just understand that they are wired VERY differently and it important for the home inspector to know these differences.
Often the service size itself is adequate for the home—the panel simply lacks the space to add new circuits.
This means that when all those top breakers are turned off—all power to the breakers in the panel will be off—including the lower breakers.
Here is another panel with only three double pole breakers in the top six spaces but one of them has blue wires that run to the bus bars for the lower circuits.