That's why breaker panels are provided with knock-out blanks. You only remove the blanks that you need.
If you have removed too many of the blanks, install unused breakers in the empty spaces.
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Your local hardware store sells breaker knockout blanks or plugs so you do not have to install unused breakers. They are simply plastic spacers that snap into your breaker cover (called a dead front) to keep energized parts from being too easily available for contact. -- Sparkfighter
only if listed in the panel board
If you are talking about a breaker in a house panel then a 15 amp breaker would be used. It is the smallest amperage breaker that you will find in a house panel.
The biggest circuit breaker in any home is the main breaker located in your main breaker panel that is installed where your electrical service cable comes into your home.
In North America the smallest size breaker found in a home distribution panel is rated at 15 amps
Look to see if the 30 amp panel is fed with a two wire or a three wire. If it is a two wire then you are out of luck. If the panel is fed with a three wire then the panel should have the neutral terminated in the panel. It is this neutral that you need for 120 volt connections. You didn't state how many panel slots there are in the panel. If you are able install a 15 amp breaker into the panel and connect the wires going to the load. The black wire will go to the breaker and the white wire will go to the neutral bar in the panel.
The panel and breaker have to be of the same manufacturer. This way the breaker will fit into the panel. If the panel has a push in bus bar, the breaker must also be the type to accept the bus bar. If the bus bars in the panel are of the bolt in type then the breaker also has to be a bolt in breaker.
It is inserting a breaker into a service panel.
only if listed in the panel board
No, a Cutler Hammer will not work in a GE panel or vice versa.
A 100-A sub-panel would be fed from a 100-A breaker.
If you are talking about a breaker in a house panel then a 15 amp breaker would be used. It is the smallest amperage breaker that you will find in a house panel.
The biggest circuit breaker in any home is the main breaker located in your main breaker panel that is installed where your electrical service cable comes into your home.
Possibly. Depends on which model Siemens breaker you have.
5'6"
In North America the smallest size breaker found in a home distribution panel is rated at 15 amps
Look to see if the 30 amp panel is fed with a two wire or a three wire. If it is a two wire then you are out of luck. If the panel is fed with a three wire then the panel should have the neutral terminated in the panel. It is this neutral that you need for 120 volt connections. You didn't state how many panel slots there are in the panel. If you are able install a 15 amp breaker into the panel and connect the wires going to the load. The black wire will go to the breaker and the white wire will go to the neutral bar in the panel.
Simple. Your main electrical panel will have a "main breaker". This will be a two pole breaker, usually at the top of the panel. It will have a number on the breaker "handle" such as 150 or 200. This is the maximum number of amps your panel can supply. Most newer homes, 1975 and newer have a 200 amp service.