Buying a replacement circuit breaker can be confusing if you don't know what the information printed on the breaker means.
A typical circuit breaker label may contain several numbers, letters, symbols, and certification marks. These markings can tell you important information about the breaker, including its amperage, voltage, number of poles, interrupting rating, breaker type, and applicable system requirements.
Understanding these specifications is especially important when purchasing replacement breakers for commercial and industrial electrical equipment.
For example, a breaker may be marked with information such as:
200A | 240V | 3 Pole | 10kAIC | Type TQD
Each of these specifications provides different information.
In this guide, we'll explain how to read circuit breaker labels and what the most important specifications mean.
Safety note: Circuit breakers and electrical panels can contain hazardous voltages and high fault-current levels. Do not open, remove, test, or install electrical equipment unless you are qualified to do so. When in doubt, consult a licensed electrician or qualified electrical professional.
Why Is It Important to Read a Circuit Breaker Label?
The label helps you identify the breaker and determine whether it may be suitable for a particular application.
A breaker that looks similar to another model may have completely different specifications.
Before purchasing a replacement, the label can help you identify:
- Manufacturer
- Model or catalog number
- Ampere rating
- Voltage rating
- Number of poles
- Interrupting rating
- Breaker series or type
- Frequency
- Certification markings
- Temperature ratings
- Special application information
These details are useful when comparing a replacement breaker with the existing equipment.
Circuit Breaker Label Example
Let's use a simplified example:
TQD22200
200A
240V
3 Pole
10kAIC
Type TQD
Here's what each specification tells you:
| Label Information | Meaning |
|---|---|
| TQD22200 | Model/catalog identification |
| 200A | Current rating |
| 240V | Voltage rating |
| 3 Pole | Number of poles |
| 10kAIC | Interrupting rating |
| Type TQD | Breaker series/type |
Understanding these individual specifications makes it much easier to identify the correct replacement.
1. Manufacturer Name
The first thing to look for is the manufacturer.
Common circuit breaker manufacturers include:
- GE
- Eaton
- Siemens
- Square D
- ABB
- Schneider Electric
The manufacturer is important because breakers from different manufacturers are not automatically interchangeable.
Even breakers from the same manufacturer may belong to different product families.
Why It Matters
Suppose your panel uses a specific breaker series.
Another breaker may have:
- The same amp rating
- The same voltage
- The same number of poles
but still be incompatible because its mounting system or bus connection is different.
Always identify the manufacturer before searching for a replacement.
2. Model Number or Catalog Number
The model number or catalog number is one of the most valuable pieces of information on a circuit breaker.
It allows you to identify the specific product rather than searching by general specifications.
For example, a model number might look like:
TQD22200
The exact meaning of individual characters varies by manufacturer, so you should use the complete catalog number when searching for product documentation or a replacement.
Best Practice
Instead of searching:
200 amp breaker
search:
Manufacturer + complete model number
This can significantly reduce the possibility of selecting the wrong product.
3. Ampere Rating
The ampere rating is usually one of the most visible numbers on a circuit breaker.
It may be marked as:
- 15A
- 20A
- 30A
- 60A
- 100A
- 200A
- 400A
The ampere rating indicates the breaker's rated current for its intended application.
Example
If a breaker is marked:
200A
it has a 200 amp current rating.
However, this does not mean that every 200 amp breaker is interchangeable.
You still need to check:
- Voltage
- Poles
- Interrupting rating
- Breaker type
- Panel compatibility
- Mounting configuration
4. Voltage Rating
The voltage rating tells you the maximum system voltage for which the breaker is rated under specified conditions.
You may see ratings such as:
- 120V
- 120/240V
- 208V
- 240V
- 480V
- 600V
Commercial and industrial breakers can have substantially different voltage specifications from residential branch breakers.
Important
Do not assume that a breaker is compatible simply because the amp rating matches.
The voltage rating must also be appropriate for the electrical system.
5. Number of Poles
Look for markings such as:
- 1 Pole
- 2 Pole
- 3 Pole
- 4 Pole
The number of poles indicates how many circuit conductors the breaker is designed to control and protect, according to its configuration.
1-Pole Breaker
Commonly used for branch circuits in systems where one energized conductor is switched.
2-Pole Breaker
Commonly used for circuits requiring two-pole protection and simultaneous disconnection, including many 208V or 240V applications.
3-Pole Breaker
Commonly used in three-phase electrical systems.
Example
A breaker labeled:
200A – 3 Pole
is a 200 amp, three-pole breaker.
It should not automatically be replaced with a 200 amp, two-pole breaker.
6. Interrupting Rating — kA or kAIC
One of the most misunderstood specifications on a breaker label is the interrupting rating.
It may appear as:
- 5kA
- 10kA
- 14kA
- 22kA
- 25kA
- 35kA
- 65kA
- 100kA
You may also see kAIC.
What Does 10kA Mean?
10kA = 10,000 amps
But it does not mean that the breaker normally carries 10,000 amps.
Instead, it refers to the breaker's rated ability to interrupt a fault current under specified conditions.
For example:
200A, 240V, 10kAIC
means the breaker has:
- 200 amp current rating
- 240 volt rating
- 10,000 amp interrupting rating
These are three different specifications.
7. Breaker Type or Series
Circuit breakers often have a specific type, series, or family.
Examples might include markings such as:
- TQD
- QO
- QOB
- THQB
- THQC
- ED
- FD
The exact meaning depends on the manufacturer.
The series is particularly important because it can determine:
- Panel compatibility
- Mounting configuration
- Available ratings
- Accessories
- Physical design
- Electrical characteristics
Don't Ignore the Series
A breaker marked "200A" isn't enough information to identify the correct product.
The series/type can be just as important as the amperage.
8. Frequency Rating
Some circuit breakers include a frequency rating such as:
50/60 Hz
This indicates the frequency for which the product is rated under specified conditions.
In many commercial and industrial electrical systems, frequency is an important part of equipment specifications.
Always compare the breaker documentation with the requirements of the electrical system.
9. Temperature Rating
Circuit breaker labels or documentation may include temperature information.
You may see specifications related to:
- 40°C
- 50°C
- 60°C
- 75°C
Temperature ratings can relate to the operating environment, terminals, conductors, or other product-specific conditions.
Don't interpret a temperature marking without referring to the manufacturer's documentation because its meaning depends on where and how the rating is specified.
10. Certification and Listing Marks
You may also see certification or listing symbols on a circuit breaker.
For example, a breaker may carry markings associated with organizations or standards such as:
- UL
- CSA
- IEC
- Other applicable certification organizations
These markings can provide information about the standards under which the product has been evaluated.
When purchasing electrical equipment, make sure the product's certifications and approvals are appropriate for the intended application.
11. Trip Information
Some breakers provide additional information about their trip characteristics or trip unit.
Depending on the breaker, you may encounter:
- Thermal-magnetic trip
- Electronic trip
- Adjustable trip
- Instantaneous protection
- Long-time protection
- Short-time protection
- Ground-fault protection
Not every breaker provides all of these features.
This information becomes particularly important when selecting commercial and industrial circuit breakers.
12. Terminal and Wire Information
Circuit breaker documentation may also specify the type and size of conductors that can be connected to the breaker.
Depending on the product, specifications may include:
- Wire size
- Conductor material
- Terminal type
- Torque requirements
- Temperature rating
These requirements should be followed according to the manufacturer's installation instructions.
Never assume that a conductor fits safely simply because it physically fits into a terminal.
How to Read a Circuit Breaker Label Step by Step
If you're trying to identify an unknown breaker, follow this process.
Step 1: Find the Manufacturer
Look for the manufacturer's name or logo.
Step 2: Find the Model Number
Record the complete model/catalog number.
Avoid leaving out letters or numbers.
Step 3: Identify the Amp Rating
Look for the current rating, such as:
100A
or
200A
Step 4: Check the Voltage
Look for the rated voltage.
For example:
240V
or
480V
Step 5: Count the Poles
Determine whether the breaker is:
- Single-pole
- 2-pole
- 3-pole
- Another configuration
Step 6: Find the Interrupting Rating
Look for:
kA
or
kAIC
This tells you the breaker's rated fault-current interrupting capacity under specified conditions.
Step 7: Identify the Breaker Series
Look for the breaker family or type.
Step 8: Check the Panel
Finally, verify that the breaker is approved and compatible with the intended panel or electrical equipment.
Example: Reading a 200 Amp Circuit Breaker
Suppose a breaker has the following markings:
GE
TQD22200
200A
240V
3 Pole
10kAIC
Here's how to interpret it:
GE
→ Manufacturer
TQD22200
→ Model/catalog identification
200A
→ Current rating
240V
→ Voltage rating
3 Pole
→ Three-pole configuration
10kAIC
→ 10,000 amp rated interrupting capacity under specified conditions
This information gives a much clearer picture of the product than simply knowing it is a "200 amp breaker."
How Circuit Breaker Specifications Help You Find a Replacement
When replacing a breaker, write down every specification you can identify.
Recommended Information
Manufacturer:
GE
Model:
TQD22200
Current:
200A
Voltage:
240V
Poles:
3
Interrupting Rating:
10kAIC
Series:
TQD
Then compare those details against the replacement product.
This is much safer and more accurate than searching for a generic breaker based only on amperage.
Circuit Breaker Specification Checklist
Use this checklist before purchasing:
| Specification | What to Check |
|---|---|
| Manufacturer | Brand |
| Model/Catalog Number | Exact identification |
| Amp Rating | Current rating |
| Voltage | System voltage |
| Poles | 1, 2, 3, etc. |
| Interrupting Rating | kA/kAIC |
| Breaker Series | Product family |
| Trip Type | Thermal-magnetic/electronic, if applicable |
| Mounting | Plug-on/bolt-on/etc. |
| Panel Compatibility | Approved equipment |
| Certifications | Applicable listings |
| Terminal Requirements | Wire and torque specifications |
Why You Shouldn't Choose a Breaker by Appearance
Two circuit breakers can look nearly identical but have different electrical characteristics.
For example, two breakers may both appear to be:
200A + 3 Pole
but differ in:
- Voltage
- Interrupting rating
- Series
- Mounting
- Panel compatibility
- Trip characteristics
This is why reading the label is so important.
Physical appearance is not enough to establish compatibility.
Common Circuit Breaker Label Mistakes
Mistake #1: Confusing 10kA With 10,000 Amp Rating
10kA is typically an interrupting rating, not the breaker's normal current rating.
Mistake #2: Looking Only at the Amp Rating
A 200 amp breaker is not automatically interchangeable with every other 200 amp breaker.
Mistake #3: Ignoring the Model Number
The model or catalog number can provide much more information than the amp rating.
Mistake #4: Ignoring Pole Configuration
A 2-pole and 3-pole breaker serve different circuit configurations.
Mistake #5: Assuming a Physical Fit Means Compatibility
A breaker may physically fit while not being approved for the panel.
Frequently Asked Questions
What information is printed on a circuit breaker?
Depending on the product, a circuit breaker may include the manufacturer, catalog number, amp rating, voltage rating, pole configuration, interrupting rating, breaker series, certification marks, and other technical information.
What does the amp number on a breaker mean?
The amp number indicates the breaker's rated current for its intended application. For example, a 200A breaker has a 200 amp current rating.
What does kA mean on a circuit breaker?
kA means kiloamps. On a breaker, it commonly identifies the interrupting rating—the amount of fault current the breaker is rated to interrupt under specified conditions.
What does kAIC mean?
kAIC refers to the breaker's rated interrupting capacity, expressed in kiloamps, under specified conditions.
What does 3 Pole mean on a circuit breaker?
A 3-pole breaker is designed to control and protect three circuit conductors simultaneously and is commonly used in three-phase electrical systems.
Can I identify a replacement breaker from the label?
Often, yes. The manufacturer, model number, series, amperage, voltage, poles, and interrupting rating provide valuable information for identifying a replacement. Panel compatibility should still be verified.
Does a higher kAIC rating make a breaker better?
Not necessarily. The interrupting rating needs to be appropriate for the available fault current and other system requirements. A higher rating does not automatically make a breaker suitable for every application.
Can two breakers with the same specifications be interchangeable?
Not automatically. Panel compatibility, mounting configuration, manufacturer approval, certification, and other product-specific requirements must also be considered.
Final Thoughts
Learning how to read circuit breaker labels and specifications can make the replacement-buying process much easier.
Instead of focusing on a single number such as "200A," look at the complete product information.
The most important specifications to identify include:
- Manufacturer
- Model or catalog number
- Current rating
- Voltage rating
- Number of poles
- Interrupting rating
- Breaker series
- Trip characteristics
- Mounting configuration
- Panel compatibility
For commercial and industrial breakers, these details can be particularly important.
If you're replacing a breaker such as the GE TQD22200, record the complete markings from the existing breaker and compare them with the specifications of the replacement product.
The more complete the identification information, the lower the risk of purchasing the wrong breaker.