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QOB140-1021
Free Shipping Over $99
QOB140-1021
Free Shipping Over $99
QOB140-1021
Free Shipping Over $99
QOB140-1021
Free Shipping Over $99
QOB140-1021
QOB140-1021
QOB140-1021
QOB140-1021

Square D QOB140-1021 QOB1401021 - 40A 1 Pole Miniature Circuit Breaker

  • 40A
  • 1 Pole
  • Bolt-On
Square D QOB140-1021
QOB1401021 - 40A 1 Pole Miniature Circuit Breaker
Brand Square D
SKU QOB140-1021
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  • 40A
  • 1 Pole
  • Bolt-On

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QOB140-1021

Square D QOB1401021 - 40A 1 Pole Miniature Circuit Breaker

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$248.85 No Stock

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Description SpecificationsProduct FAQs SuperClub Warranties Shipping Reviews 4.9 (211)

Description

Part of the QO family, the QOB140-1021 is a 40A, single-pole breaker equipped with a 120/208/240VAC factory-installed shunt trip. This allows users to remotely open the circuit for enhanced safety and control. Utilizing a rugged bolt-on connection, this breaker mounts firmly into Square D NQ and NQOD panelboards. The bolt-on mechanism is ideal for commercial environments. Delivering 10 kAIC at 120/240VAC, it features the Visi-Trip window to quickly identify tripped status and is HACR rated.

Specifications

Key specifications
Brand Square D
Series QOB
Amperage 40A
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 Box Lugs
For Use With NQ Panelboards, NQOD Panelboards
Wire Gauge 8-2 AWG (Al/Cu)
Max Wire 2 AWG
Min Wire 8 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, Padlock Attachment
Accessories Load Side Lugs Included, Mounting Hardware, Shunt Trip (Factory Installed)
Standards UL 489, CSA C22.2 No. 5, HACR
Approval CSA, HACR, UL
Temp Rating 40C
Construction Features HACR Rated, Visual Trip Indicator

Product FAQs

7 answers
What panelboards are compatible with the QOB1401021 circuit breaker?

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

What does the 1021 suffix indicate on this Square D breaker?

The 1021 suffix means the breaker includes a factory-installed 120/240VAC shunt trip accessory. This allows the circuit breaker to be opened remotely via a control signal.

How much panel space does the QOB1401021 require?

Although it is a 1-pole breaker, the factory-installed shunt trip accessory requires an additional pole space. The unit is 1.5 inches wide and will occupy two spaces total in your panelboard.

What wire sizes are accepted by the terminals on this 40A breaker?

The box lugs on this breaker accept 8 AWG to 2 AWG aluminum or copper conductors.

Can the QOB1401021 be used in direct current (DC) applications?

Yes, this breaker is rated for use on DC systems up to 48VDC, where it provides an interrupting rating of 5kAIC.

How can I tell if this breaker has tripped?

This breaker features the Square D Visi-Trip indicator. When a trip occurs, the handle moves to a center position and a bright red indicator appears in a window on the face of the breaker.

Is the QOB1401021 rated for heating, air conditioning, and refrigeration (HACR) equipment?

Yes, standard QOB thermal magnetic circuit breakers are HACR rated for use with multi-motor and combination loads found in HVAC equipment.

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Shipping

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Parcel shipments with item value over $99 qualify for free economy shipping within the continental US. Please call to confirm special handling instructions. We do not charge a handling fee or require a minimum amount on any order. SuperBreakers does not ship on customer accounts.

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Reviews

4.9
Rated 4.9 out of 5 stars
Based on 211 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.
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211 reviews
  • ML
    Mike L.
    Verified Buyer
    Reviewing
    Square D QOB250 - 50A 2 Pole Miniature Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    10/9/26
    breaker orders

    Breaker worked out great

    Can not be happier with the quick shipping

    Was this helpful?
  • RC
    Richard C.
    Verified Buyer
    Reviewing
    Square D QOB380 - 80A 3 Pole Miniature Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    10/7/26
    Great price quick turn around

    Thank you for getting me the breaker in a timely fashion

    Was this helpful?
  • DS
    Darren S.
    Verified Buyer
    Reviewing
    Square D QOB250 - 50A 2 Pole Miniature Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    10/5/26
    Airport taxi lighting

    After contactor replacement we discovered bad breakers and were able to get replacements from Super Breakers in 2 days. THANK YOU SUPER BREAKERS..

    Was this helpful?
  • MR
    Miguel R.
    Verified Buyer
    Reviewing
    Square D QOB220GFI - 20A GFCI Miniature Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    10/1/26
    Excellent

    Excellent product and service

    Was this helpful?
  • MR
    Miguel R.
    Verified Buyer
    Reviewing
    Square D QOB230GFI - 30A GFCI Miniature Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    10/1/26
    Excellent

    Excellent product and service

    Was this helpful?