A 100-A sub-panel would be fed from a 100-A breaker.
For a 100 Amp breaker panel it would be 2 AWG. For 150 Amps it would require 2/0 (2 ought) aluminum wire.
Yes, but they obviously cannot be simultaneously loaded their maximum loads because the 400-amp breaker will blow well before that. Similarly, you can have multiple 100-amp panels fed from a 200-Amp main breaker, knowing that you will NEVER have 100 amps running in all panels at the same time.
The size breaker you use is determined by the size wire used in the circuit. If you use AWG #12/2 wire then use a 20 amp breaker. If you use AWG # 14/2 then use a 15 amp breaker.
In North America the standard sizes for breakers are 15, 20, 30, and 40 amps. The 15 amp size breaker is used in general circuit wiring. The 20 amp size breaker is used for dedicated appliance receptacles, hot water tank and baseboard heating. The 30 amp size breaker is used for a clothes dryer. The 40 amp size breaker is used for the electric range.
A 100-A sub-panel would be fed from a 100-A breaker.
There are two things to think about here. First of all a 200 amp breaker will not physically fit into a 100 amp panel. This is so designed because the panel buss is not designed to conduct 200 amps before the current is cut off. A 100 amp rating on the panel is the maximum amount of current that the manufacturer states, that can be handled safely. Second if the 200 amp breaker is in the main panel then everything downstream from that breaker has to be rated for 200 amp conductivity. The wire size will have to be 3/0 from the breaker to the first over current device in the sub panel which will be the sub panel's main breaker. The sub panel can not be a load center but will have to be a combination panel. I doubt that the 100 amp sub panel's main breaker lugs would be large enough to connect the 3/0 cable.
For a 100 Amp breaker panel it would be 2 AWG. For 150 Amps it would require 2/0 (2 ought) aluminum wire.
NO!
A 15 amp breaker is not sufficient for a 225 amp load. You would need a breaker that matches the load current, such as a 225 amp breaker. Using a 15 amp breaker for a 225 amp load would cause the breaker to trip immediately due to overcurrent.
In North America this size breaker could be used on a welding machine. A range in the home would use a 40 amp two pole breaker.
No, a double pole 50 amp breaker protects a 240 volt supply at 50 amps. The number that is on the handle of the breaker is the amperage that the breaker will trip at if an overload occurs on the circuit.
probally about 100 dollars
If a 100 amp breaker keeps tripping there is an overload on the system.
Yes, a 100 amp main panel can have 2 separate 50 amp circuits protected by 50 amp breakers. This configuration allows for two separate circuits drawing up to 50 amps each from the main panel without overloading the panel's 100 amp capacity.
Yes, but they obviously cannot be simultaneously loaded their maximum loads because the 400-amp breaker will blow well before that. Similarly, you can have multiple 100-amp panels fed from a 200-Amp main breaker, knowing that you will NEVER have 100 amps running in all panels at the same time.
No, a Meter Main Combo typically includes the main breaker as part of its design, so you would not need an additional main breaker in the panel. The main breaker in the Meter Main Combo serves as the disconnect for the panel.