Your breaker panel has two separate bus bars and it is certainly best to balance your load between each bus. Typically every other breaker, as you move vertically, is an alternating bus.
While you can add up the ratings on each bus to try and balance, this will not provide the best balance in that many breakers may operate at no where near their rating. The best way is to have an electrician measure the current on each bus with a clamp-on amp meter.
While this balance is ideal, it is usually only necessary if you are having a problem with the unbalanced load, like all the lights in your house dimming when the air conditioner turns on.
On your ganged 30 amp breakers, 30 amps through either will trip that breaker.
Ampere (current) interupting capacity - the maximum current the breaker can interupt/switch/break, without damage.
I am assuming by your description that the panel is protected by a 90 amp breaker and the breakers in the panel when added up is 200. This is okay as long as your 90 amp breaker trips on a regular basis. It is typical for the breakers to add up to more than the main breaker under the assumption that you would rarely be running each circuit at its maximum capacity.
The electrical terminology for this type of breaker is a tandem breaker. It is where two breakers circuits can be in the same one breaker slot in a distribution panel. On this type of breaker there will be two output for a circuit value of what ever the breaker is rated for.
mineature cicuit breaker
No, add new breaker,find a junction box and split the series, or add a box and split the load. You only need to do this if the breaker is tripping from overload. 12ga wire should have a 20amp breaker not a 15amp. If I understand your question,wired in parallel, this would be one hot connected to two breakers, first off two breakers is 220v not 120v , and 220v has two hot wires. Never connect two breakers together on one line.
Ampere (current) interupting capacity - the maximum current the breaker can interupt/switch/break, without damage.
Hard to define... A four year old child has the strength to physically "make" a typical household circuit breaker, while a teen would be able to "make" a typical industrial circuit breaker. (The latter breaker being physically much larger than the former.) Circuit breakers have their "breaking capacity" rated in AMPS. A typical household breaker is rated at 20, 30 or 50 Amps. Industrial breakers might be rated at 500 amps or a thousand or even more. Hope this helps but if it didn't answer your question, please rephrase it and ask again.
I am assuming by your description that the panel is protected by a 90 amp breaker and the breakers in the panel when added up is 200. This is okay as long as your 90 amp breaker trips on a regular basis. It is typical for the breakers to add up to more than the main breaker under the assumption that you would rarely be running each circuit at its maximum capacity.
The electrical terminology for this type of breaker is a tandem breaker. It is where two breakers circuits can be in the same one breaker slot in a distribution panel. On this type of breaker there will be two output for a circuit value of what ever the breaker is rated for.
mineature cicuit breaker
Making capacity is the max fault current it can carry during closing of breaker, e.g. You are closing a breaker on fault. The making capacity is always higher because it is expressed in peak value not rms, and also because of the DC offset, voltage and PF while closing
First you need to determine if addition of the new breakers will exceed the 200A service under normal operating conditions. If so you will need to go to power company and increase service and put in a larger main panel. If you have the capacity for the extra current you can add a sub-panel and add the breakers there as well as the breakers you will remove from main panel to accommodate the sub-panel breaker. Another way depends on what breakers are in current panel. There are some breakers that can be duplexed in the same space as a single breaker.
No, add new breaker,find a junction box and split the series, or add a box and split the load. You only need to do this if the breaker is tripping from overload. 12ga wire should have a 20amp breaker not a 15amp. If I understand your question,wired in parallel, this would be one hot connected to two breakers, first off two breakers is 220v not 120v , and 220v has two hot wires. Never connect two breakers together on one line.
To replace breakers in an electrical box it is extremely important the replace the breaker with the same wattage. Do not replace a 100 breaker with a 20 breaker is can cause damage.
Two single-pole 30 amp breakers tied together make a two-pole 30 amp breaker. From this you can power a device that requires 220-240 volts, typically.
On most residential circuit breaker boxes in North America, each individual breaker represents one 120-volt circuit. Two breakers ganged together represent a 240-volt circuit.
You need to calculate how much the total current is likely to be at any moment. It's probable that the total load will be less than the sum of the individual breakers, 200 amps, but how much less depends on local conditions.