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A #3 copper conductor with an insulation factor of 90 degrees C is rated at 115 amps. Even though the panel is rated at a higher amperage it is the main breaker that governs the wire size.

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โˆ™ 2015-07-15 06:01:10
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Q: What wire size do you need for a 125 amp panel with a 100 amp main breaker?
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What is the minimum size breaker panel for a home main service?

50 amps

What is the minimum size breaker panel for a home's main service?

50 amps

What is the minimum size breaker panel required for a homes main service?

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How do you read breaker box amps?

The main breaker will have marking indicating size of electrical service, or if it is a fuse system....the fuses will have current ratings. If it is a subpanel, it might not have a main breaker. In this case you would have to look in the panel that the feed is coming from and find the size of the breaker that is feeding it. In either case you must look for the manufacturer's label that will have the maximum current the panel can handle, make sure the breaker feeding the panel doesn't exceed this rating.

What is the minimum size breaker panel for a home?

In North America the smallest size breaker found in a home distribution panel is rated at 15 amps

What size breaker do you use for a 100 amp sub panel?

A 100-A sub-panel would be fed from a 100-A breaker.

How do you determine if you have 100 or 200 amp service?

Look at the value of the breaker or fuses that control your main electric panel. look at the wire size coming in to the main lugs on service panel, I am assuming you don't have a main breaker or you would look at the breaker rating to determine service size. 2/0 copper or 4/0 aluminum service size 200 amps, #4 copper or # 2 aluminum 100 amp.

Can you downgrade from a 125 amp main outside breaker to 100 amp using the same type of breaker is there a safety issue?

You can reduce the breaker size because that limits the current that can reach the main panel. There is no safety issue other than the significant danger in an unskilled person changing out a main breaker.

What is the smallest size circuit breaker found in the normal home?

In North America the smallest size breaker in a distribution panel is a 15 amp breaker.

Can you upgrade a 100A main circuit breaker to a higher amp?

It depends on a number of factors. The size of the service wires, the meter rating, the main breaker panel rating, etc. will have to be rated for the amperage you want to go up to.

Is the size of main circuit breaker greater than the size of sub circuit breakers?

Typically yes because that is what makes sense. However, the subpanel could have the same size breaker as long as the panel were rated for that amperage and the wire sizes were appropriate.

Do you need a main disconnect on the feeder wires running to a detached garage running from the box in the house?

You will need a breaker in your house panel to protect the wire feeders that supply the panel in the garage. The terminology for this setup is called a sub panel. At the garage end you will need a disconnect at that panel as the garage is not attached to the house. You might want to consider a 100 amp combination panel at the garage as it has a built in main disconnect and spaces for 12 or 24 breakers depending on the size of panel you select.

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