Circuit breaker is protection tool for your electrical circuits and home appliances. It lets a specific amount of current through a circuit. So, a breaker keeps your appliances protected and safe. There are breakers of various ratings that complies for your specific circuit design. But is it safe to change a circuit breaker from 20 to 30 amp?

For a circuit designed for 20 Amp current rating, it is not safe to replace it with a 30 Amp breaker. If your circuit consists of wires that can associate with a 30 Amp current flow, then it is safe to use a 30 Amp breaker.

Before changing your circuit breaker, you should learn the basics of a circuit breaker. It is important to maintain the amperage of the breakers according to the circuit wires and other current sensitive materials. I am going to highlight those important things for you here in this article.

How To Change A Circuit Breaker From 20 To 30 Amp

What Is The Amperage Of A Circuit Breaker?

The amperage of a circuit breaker indicates the amount of current it will let through it for the circuit to consume. When the current flow exceeds the amperage of the breaker, it simply trips off the circuit and breaks the current flow.

Let’s come to a question now, what is the meaning of a 20 Amp circuit breaker?

A 20 Amp circuit breaker means, at ambient temperature, it will not trip until the current flowing through it exceeds 20 Amp.

This is called the tripping current. It should be noted that, the tripping current may vary slightly due to the change in the temperature.

How To Wire A Circuit Breaker?

A circuit breaker is simply put in series with the supply line while wiring. The breaker can be single pole or a double pole breaker.

In case of a single pole breaker, only the hot wire is connected to the breaker. On the other hand, both the hot wire and neutral wire is connected to a double pole breaker.

Let me show you more of a detail for an easier understanding.

Fig. 1: Wiring different types of breaker.

I think you have already found out how to wire a breaker watching the circuit diagram above. There are different slots for the line and neutral in a double pole breaker.

In the diagram you can see the incoming wires are connected in the upper portion of the breaker. And the outgoing wires are connected in the lower portion.

In case of the single pole breaker there is slot for the hot line wire only. There is no slot for the neutral. When the current through the hot line wire exceeds the limit, it simply opens the circuit by disconnecting the connection.

In houses or buildings, the 2 pole breaker is used as the main breaker for the whole circuit. On the other hand, the single pole breakers are wired in every little unit to give protection to individual appliances or a whole room.

How To Change A Circuit Breaker From 20 To 30 Amp?

To change a circuit breaker, you have to turn off the current supply in the first place, then disconnect the wires, replace the 20 Amp breaker with the 30 Amp breaker and then reconnect the wires again.

After wiring the new breaker properly, turn it on to energize and establish the circuit connection again.

Let’s put this into some easy looking steps:

Step 1:

Turn off the main circuit breaker of the house to cut off power supply to the targeted circuit breaker.

Step 2:

Open the panel and unscrew the 20 amp circuit breaker. Test the terminals with a tester to ensure there is no voltage supply.

Step 3:

Unscrew the wires of the 20 amp breaker. Check the gauge of the wire.

If the wire does not comply with 30 ampere breaker, you will need to change them. In that case you should contact an electrician.

Step 4:

Replace the 20 Amp breaker with a 30 Amp breaker and connect the wires properly as directed.

Step 5:

Attach the breaker to the panel and put the panel back to normal.

What To Keep In Mind While Replacing A Circuit Breaker?

You must be conscious about the current capacity of the wire you are using for your circuit.

If the wires are not good enough for a 30 ampere current flow then you should not change a 20 ampere breaker with a 30 ampere breaker.

A 20 amp breaker must associate with atleast 12 gauge wire. For a 30 amp breaker, the wires should be atleast 10 gauge.

Failing to choose the right size wire may result in melting and flame in the circuit. So, always abide by the rules and regulations of electrical safety codes.

Can You Put A 30 Amp Breaker In A House?

Yes, it is okay put a 30 amp breaker in a house. In this case you have maintain the protocols while plugging devices into the circuit.

First of all, the wires and accessories must comply to the current rating. If the wires are not thick enough, it can get caught in fire.

Secondly, do not plug in devices that can exceed the current rating, doing so the circuit will be tripped off.

There is a limited number of devices you can plug in a circuit. If you ask me how many ceiling fans on a 15 amp circuit? You can connect almost 18 fans on a 15-amp circuit.

How To Change The Amperage Of A Circuit Breaker?

You can change the amperage or breaker amp by changing the circuit breaker for your circuit. In this case simply follow the steps I have described above to get your work done easily.

Doing so I hope you will know what you need to do to reach your goal. But always keep in mind that the accessories related to the breaker must match the rating of the breaker.

How Many Amp Can A 30 Amp Breaker Handle Safely?

A 30 amp breaker can handle 24 amp safely. It is a very simple calculation. Normally the safe range for a circuit breaker is the 80 percent of the rated current. So, 80% of a 30 amp breaker is: 0.8*30= 24 amp. This kind of like how many watts can a power strip handle. There are always some limitations to every device.

What Is The Difference Between A 20 Amp Breaker And A 30 Amp Breaker?

The main differences are the current rating and the accessories ratings. A 20 amp breaker allows a maximum of 20 amp current while a 30 amp breaker allows a maximum of 30 amp current. A 20 amp breaker recommends 12 guage wire while a 30 amp breaker recommends 10 gauge wire. These are the basic differences between the two breakers. Besides these there can be physical variances.

What Happens When The Current Reaches The Breaker Limit?

When the current reaches the rating of a breaker, it trips the circuit. As a result the circuit is disconnected from the source and the circuit shuts off unless there is an automatic transfer switch.


Dear readers I think you have got a good idea about the ratings of the breakers, how to change a breaker and what to look into while changing.

It is always important to know the basics about electrical and electronic items before operating them. And circuit breakers are a core device while wiring your house.

If you are thinking about changing your existing breaker, no need to panic. Now you know what are the things you need to do. So, take proper precautions and go for it. Good luck!!

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