What are the Numbers On The Mains?

When you open the circuit breaker box to replace your Federal Pacific breakers, you'll see two circuit breakers with numbers printed on them. These are the main circuit breakers, connected to the power cables which supply electricity from the power company to the whole house. The numbers printed on these circuit breakers indicate "amp capacity" or how many amps the circuit is rated to handle. For modern residential services you will see amp capacity of at least 100 amps, but often more. 150 is quite common, but there are also electrical panels and circuit breaker mains rated at between 200 and 400 amps. Older homes may be equipped with 60 amp circuit breakers, but for modern electrical needs this is usually considered insufficient.