4 Outdated and Unsafe Electrical Panels That Could .
Then the 3rd breaker supplies power to the lower breakers (see the blue wires connecting them). Why they're unsafe: By themselves, split-bus panels aren't unsafe. However, these types of panels haven't been used for over 40 years. That puts them past their expected lifespan, meaning the circuit breakers may not trip as they are designed to. Plus, electrical code no longer allows for ...