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Square D QO120DF Dual Function Miniature Circuit Breaker

  • 20A
  • 1 Pole
  • Plug-On
Square D QO120DF
Dual Function Miniature Circuit Breaker
Brand Square D
SKU QO120DF
Select Item Condition
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  • 20A
  • 1 Pole
  • Plug-On

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Square D QO120DF - 20A Dual Function Miniature Circuit Breaker

Square D QO120DF - 20A Dual Function Miniature Circuit Breaker

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$99.00 In Stock

Quantity

Description

Part of the QO series, this 20-amp dual-function breaker combines combination arc-fault and ground-fault protection into a single-pole footprint. It operates at 120VAC and is designed for residential electrical systems. Equipped with a standard pigtail neutral wire, the device mounts into traditional QO load centers and NQ panelboards. The breaker delivers a 10 kAIC interrupting rating and includes the signature Visi-Trip indicator, providing comprehensive safety for kitchens and laundry rooms.

Specifications

Key specifications
Brand Square D
Part Number QO120DF
Series QO
Amperage 20A
Poles 1
Mounting Style Plug-On
Voltage 120VAC
Phase 1
AIC Rating 10kA @ 120VAC
Fit and installation
Frame Type QO
Terminal Type Pressure Plate
For Use With QO Load Centers, NQ Panelboards
Wire Gauge 14-8 AWG (Cu/Al)
Max Wire 8 AWG
Min Wire 14 AWG
Protection and operation
Trip Technology Thermal Magnetic
Trip Function Code LIG
Trip Function Long-Time, Instantaneous, Ground Fault
Trip Adjustability Fixed
Standards and features
Special Classification Dual Function (AFCI/GFCI)
Available Options Padlock Attachment
Accessories Pigtail Neutral
Standards CSA C22.2 No. 5, UL 1699, UL 489, UL 943, HACR
Approval CSA, HACR, UL
Temp Rating 40C
Construction Features HACR Rated, SWD Rated, Visual Trip Indicator, Time Saver Diagnostics, Mercury Free

Product FAQs

9 answers
What is the difference between the QO120DF and the QO120PDF?

The QO120DF features a pigtail neutral wire, making it compatible with legacy QO load centers that lack a plug-on neutral bus. The QO120PDF is the Plug-On Neutral (PON) version designed specifically for newer PON-ready panels.

What type of protection does a dual function circuit breaker provide?

A dual function breaker like the QO120DF combines Combination Arc Fault (CAFCI) protection to prevent electrical fires and Class A Ground Fault (GFCI, 6mA) protection to prevent electrical shock in a single device.

How do I troubleshoot a tripped QO120DF breaker?

This breaker includes Square D Time Saver Diagnostics. By using the purple push-to-test button and observing the trip behavior, electricians can identify whether the circuit tripped due to an arc fault, a ground fault, or a standard overload.

What is the recommended tightening torque for the wire terminals on this breaker?

The pressure plate terminals on the QO120DF should be tightened to 35.4 lb-in (4 N.m) for 14 to 8 AWG copper or aluminum conductors.

Can I install the QO120DF in a Square D Homeline panel?

No. QO series breakers have a different mounting footprint and are not interchangeable with Homeline panels. You must use a Homeline series dual function breaker for Homeline load centers.

Is the QO120DF rated for switching duty (SWD) and HVAC equipment?

Yes, this 20-amp breaker is SWD rated for switching 120V fluorescent lighting loads and is HACR rated for use with heating, air conditioning, and refrigeration equipment.

How do I know if the breaker has tripped without opening the panel door fully?

The QO120DF features the exclusive Visi-Trip indicator. When the breaker trips, a highly visible red flag appears in the indicator window, making it easy to spot the faulted circuit at a glance.

Does this breaker meet NEC requirements for kitchen and laundry circuits?

Yes. Because it provides both CAFCI and Class A GFCI protection, it satisfies National Electrical Code (NEC) requirements for 120V, 20A branch circuits where both arc fault and ground fault protection are mandated.

Where does the white pigtail wire connect during installation?

The coiled white pigtail wire must be connected directly to the neutral bus bar in the load center to power the internal AFCI and GFCI diagnostic circuitry of the breaker.

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Reviews

4.9
Rated 4.9 out of 5 stars
Based on 285 reviews
Reviews Summary
Customers say these circuit breakers arrive quickly and work as described. Fast shipping and competitive pricing are frequently mentioned, with many noting same-day or next-day delivery. Users appreciate the wide inventory, particularly for hard-to-find older-style models unavailable locally. The products function reliably and arrive in good condition. Most customers report straightforward ordering and positive interactions. However, some experienced delivery delays or received incorrect items requiring reordering. A few noted concerns about condition upon arrival or customer service responsiveness.
Rating
Ratings
285 reviews
  • GC
    Gerard C.
    Verified Buyer
    Reviewing
    Square D QO130GFI - 30A GFCI Miniature Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    9/21/26
    Great !

    I could not find the breaker in hardwood stores. Superbreakers took car of it in a week.

  • RH
    Roy H.
    Verified Buyer
    Reviewing
    Square D QO280 - 80A 2 Pole Miniature Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    9/17/26
    Square D QO280 - 80A 2 Pole Miniature Circuit Breaker

    Exactly as described

  • KW
    Kevin W.
    Verified Buyer
    Reviewing
    Square D QO120 - 20A 1 Pole Miniature Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    9/15/26
    Great Price

    Brand spanking new!

  • CE
    christopher e.
    Verified Buyer
    Reviewing
    Square D QO115PDF - 15A Dual Function Miniature Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    9/11/26
    My breakers

    Had a hard time locating these breakers locally, when I did find 1 they wanted to charge me triple what superbreakers charged. Items delivered exactly when they said they would, were exactly what I ordered. Appreciated the ease of ordering, definitely my go to from this point on

  • JC
    Jerry C.
    Verified Buyer
    Reviewing
    Square D QO250 - 50A 2 Pole Miniature Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    9/8/26
    Great quality

    No issues