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Square D QOB370-1021 QOB3701021 - 70A 3 Pole Miniature Circuit Breaker

  • 70A
  • 3 Pole
  • Bolt-On
Square D QOB370-1021
QOB3701021 - 70A 3 Pole Miniature Circuit Breaker
Brand Square D
SKU QOB370-1021
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  • 70A
  • 3 Pole
  • Bolt-On

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Square D QOB3701021 - 70A 3 Pole Miniature Circuit Breaker

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$585.00 In Stock

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Description SpecificationsProduct FAQs SuperClub Warranties Shipping Reviews 4.9 (212)

Description

Engineered for commercial environments, this three-pole thermal-magnetic device provides reliable overcurrent protection. The integrated 120/240VAC shunt trip allows remote circuit opening. It mounts securely into Square D NQ and legacy NQOD panelboards using a bolt-on connection. Box lug terminals accept 8-2 AWG wiring. A built-in Visi-Trip indicator provides immediate visual confirmation of a tripped condition. It carries an HACR rating for HVAC equipment.

Specifications

Key specifications
Brand Square D
Part Number QOB370-1021
Series QOB
Amperage 70A
Poles 3
Mounting Style Bolt-On
Voltage 120VAC, 240VAC, 120/240VAC, 48VDC
Phase 3
AIC Rating 10kA @ 120VAC, 10kA @ 240VAC, 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 (Cu/Al)
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
Accessories Shunt Trip (Factory Installed), Load Side Lugs Included
Standards CSA C22.2 No. 5, HACR, UL 489
Approval CSA, UL
Temp Rating 40C
Construction Features HACR Rated, Visual Trip Indicator

Product FAQs

7 answers
What panelboards are compatible with the Square D QOB370-1021?

This bolt-on miniature circuit breaker is designed for installation in Square D NQ and legacy NQOD panelboards.

Can the QOB370-1021 be installed in a standard QO load center?

No. The QOB370-1021 features a bolt-on mounting design and is not compatible with standard plug-on QO load centers. It requires a panelboard equipped for bolt-on connections.

What does the -1021 suffix indicate on the QOB370-1021?

The -1021 suffix indicates that the circuit breaker includes a factory-installed 120/208/240 VAC shunt trip accessory. This allows the breaker to be opened remotely without requiring field installation of the trip coil.

What is the maximum DC voltage and interrupting rating for this breaker?

In addition to its AC ratings, the QOB370-1021 is rated for use on direct current systems up to 48VDC, with a maximum short-circuit interrupting capacity of 5kA.

How are wires terminated on the QOB370-1021?

The breaker is equipped with box lug terminals that accept 8 AWG to 2 AWG copper or aluminum wiring.

What type of trip mechanism does the QOB370-1021 use?

It utilizes a fixed thermal-magnetic trip mechanism, providing both long-time overload protection and instantaneous short-circuit protection.

How does the QOB370-1021 indicate a tripped condition?

It features the Square D Visi-Trip indicator, which displays a highly visible red flag in the breaker window when it has tripped due to an overcurrent or short-circuit event.

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Reviews

4.9
Rated 4.9 out of 5 stars
Based on 212 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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212 reviews
  • SJ
    Sheldon J. H.
    Verified Buyer
    Reviewing
    Square D QOB240 - 40A 2 Pole Miniature Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    10/12/26
    Installer

    Good price, worked great.

    Was this helpful?
  • 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?