in a house panel with a 100 amp main can u put a 100 amp breaker on the bus . like if in the panel i have 2 20 amp lighting circuit breakers and 30 amp and 50 amp range and a 100 amp below that feeding central air unit.any help would be aprecicated thanks
It is posible to have a 100 breaker for A/C, it's very common around here to have a 100 amp breaker serving a disconnect for 3 or 4 A/C units rather than having 3 or 4 diferent home runs for each unit.
To answer the guy's original question, yes it is posible, but if the A/C's draws a combined load anywhere near that 100 amps, it's too much for the panel with all the olther stuff.
Do you have a range and a dryer on this panel also? It sounds like you need to upgrade to a 200 amp service. Things would be OK, but then the 60 amp load of the AC arrives on the scene. Very possible the main could trip. Is it worth living with that chance?