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Square D QOB120HM Miniature Circuit Breaker

  • 20A
  • 1 Pole
  • Bolt-On
Square D QOB120HM
Miniature Circuit Breaker
Brand Square D
SKU QOB120HM
Select Item Condition
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  • 20A
  • 1 Pole
  • Bolt-On

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Square D QOB120HM - 20A 1 Pole Miniature Circuit Breaker

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$47.85 In Stock

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Description

Designed to accommodate demanding startup currents, this single-pole 20A breaker utilizes a high magnetic trip setting to eliminate nuisance tripping on specialized commercial loads. The bolt-on configuration ensures a rigid, reliable connection within Square D NQ and NQOD panelboards. Alongside its elevated magnetic threshold, the unit carries standard SWD and HACR ratings, making it highly versatile for switching duty and HVAC equipment protection.

Specifications

Key specifications
Brand Square D
Series QOB
Amperage 20A
Poles 1
Mounting Style Bolt-On
Voltage 120/240VAC, 48VDC
Phase 1
AIC Rating 10kA @ 120/240VAC, 5kA @ 48VDC
Fit and installation
Frame Type QOB
Terminal Type Pressure Plate
For Use With NQ Panelboards, NQOD Panelboards
Wire Gauge 14-8 AWG (Al/Cu)
Max Wire 8 AWG
Min Wire 14 AWG
Protection and operation
Trip Technology Thermal Magnetic
Trip Function Code LI
Trip Function Long-Time, Instantaneous
Trip Adjustability Fixed
Standards and features
Available Options Auxiliary Switch, Alarm Switch, Shunt Trip, Handle Padlock Attachment
Accessories Load Side Lugs Included
Standards CSA C22.2 No. 5, UL 489, HACR, RoHS
Approval CSA, HACR, RoHS, UL
Temp Rating 40C
Construction Features High Magnetic, HACR Rated, SWD Rated, Visual Trip Indicator

Product FAQs

5 answers
What panelboards are compatible with the QOB120HM circuit breaker?

This bolt-on breaker is designed specifically for Square D NQ and NQOD series panelboards. It will not fit in standard QO residential load centers, which require plug-on style breakers.

What does the HM suffix mean in the QOB120HM part number?

The HM designates this as a High Magnetic circuit breaker. It is engineered to tolerate higher initial inrush currents without nuisance tripping, making it ideal for specific motor or lighting loads.

Can the QOB120HM be used in place of a standard QOB120?

Yes. It shares the exact same physical dimensions and bolt-on mounting as the standard QOB120, but offers the added benefit of a high magnetic trip curve for high inrush applications.

Is this breaker suitable for HVAC equipment or switching lighting loads?

Yes, it is HACR rated for use with heating, air conditioning, and refrigeration equipment. It is also Switching Duty (SWD) rated, meaning it can be used to manually switch 120V fluorescent lighting circuits.

Why use a bolt-on breaker instead of a plug-on breaker?

Bolt-on breakers like the QOB120HM secure directly to the panelboard bus with a screw. This provides a robust mechanical connection that resists vibration, making it the standard choice for commercial and industrial environments.

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All International orders require a $1,000 minimum order threshold. Due to the special nature of these shipments, we require that these be placed with a SuperBreakers representative. Additional shipping and instructions will apply. All International Orders are Non-Cancel and Non-Refundable.

Reviews

4.9
Rated 4.9 out of 5 stars
Based on 205 reviews
Reviews Summary
Customers say these electrical breakers arrive exactly as ordered and work perfectly for their intended applications. They consistently praise the competitive pricing, which many report is significantly lower than local suppliers. Fast shipping and prompt delivery are frequently highlighted, with many receiving orders within days or even next-day delivery for urgent needs. The breakers arrive well-packaged and in excellent condition. Many reviews emphasize the company's extensive inventory availability, particularly for hard-to-find breakers. One customer experienced difficulty with order cancellation and was charged a restocking fee, which caused dissatisfaction.
Rating
Ratings
205 reviews
  • BL
    BOOSTIX L.
    Verified Buyer
    Reviewing
    Square D QOB220 - 20A 2 Pole Miniature Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    8/17/26
    QOB220

    That's nice breakers!

  • PH
    Paul H.
    Verified Buyer
    Reviewing
    Square D QOB330 - 30A 3 Pole Miniature Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    8/5/26
    Quick shipping and delivery

    Shipped and delivered on time for installation at one of our projects. Thank you!

  • RM
    Rick M.
    Verified Buyer
    Reviewing
    Square D QOB220 - 20A 2 Pole Miniature Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    8/3/26
    Project Mgr

    Just what I needed.

  • DH
    Doug H.
    Verified Buyer
    Reviewing
    Square D QOB220 - 20A 2 Pole Miniature Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    8/3/26
    Square D QOB breakers

    As always, our order arrived timely, and accurate. You can’t beat their prices that’s why we have used this company for years.

  • RK
    Ryan K.
    Verified Buyer
    Reviewing
    Square D QOB230VH - 30A 2 Pole Miniature Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    7/1/26
    Awesome

    Worked great