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Square D FAL36040-1121 Molded Case Circuit Breaker

  • 40A
  • 3 Pole
  • Unit Mount
Square D FAL36040-1121
Molded Case Circuit Breaker
Brand Square D
SKU FAL36040-1121
Select Item Condition
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  • 40A
  • 3 Pole
  • Unit Mount

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Square D FAL36040-1121 - 40A 3 Pole Molded Case Circuit Breaker

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$792.40 No Stock

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Description SpecificationsProduct FAQs SuperClub Warranties Shipping Reviews 5.0 (39)

Description

Part of the legacy F-frame series, the Square D FAL36040-1121 is a 3-pole, 40A molded case circuit breaker built for commercial power distribution. It utilizes thermal-magnetic technology for reliable long-time and instantaneous (LI) protection. This unit-mount breaker installs into Square D enclosures and switchboards. For modern upgrades, it crosses over to the PowerPact BDL36040 when equipped with a UVR. Rated 18 kAIC at 480V, it features a factory-installed 120V undervoltage release.

Specifications

Key specifications
Brand Square D
Part Number FAL36040-1121
Series FAL
Amperage 40A
Poles 3
Mounting Style Unit Mount
Voltage 240VAC, 480VAC, 600VAC, 250VDC
Phase 3
AIC Rating 25kA @ 240VAC, 18kA @ 480VAC, 14kA @ 600VAC, 10kA @ 250VDC
Fit and installation
Frame Type FAL
Terminal Type Lugs
For Use With Square D Enclosures, Switchboards, Panelboards (Unit Mount)
Wire Gauge 14-1/0 AWG (Cu), 12-1/0 AWG (Al)
Max Wire 1/0 AWG
Min Wire 14 AWG
Protection and operation
Trip Technology Thermal Magnetic
Trip Function Code LI
Trip Function Long-Time, Instantaneous
Trip Adjustability Fixed Thermal, Fixed Magnetic
Standards and features
Available Options Shunt Trip, Auxiliary Switch, Alarm Switch, Padlock Attachment
Accessories Undervoltage Release (Factory Installed), Line and Load Lugs Included
Standards CSA C22.2 No. 5, HACR, IEC 60947-2, NEMA AB 1, UL 489
Approval CSA, IEC, UL
Temp Rating 40C
Construction Features HACR Rated, Visual Trip Indicator

Product FAQs

8 answers
What does the -1121 suffix mean on the FAL36040-1121?

The -1121 suffix indicates that this breaker is equipped with a factory-installed 120VAC Undervoltage Trip (UVT). The UVT requires a continuous 120V control voltage to allow the breaker to close and remain closed.

How does the undervoltage trip (UVT) affect the operation of this breaker?

The 120VAC undervoltage release will automatically trip the breaker if the control voltage drops below a safe threshold. The breaker cannot be reset or turned on until the 120V power is restored to the UVT circuit.

What type of panels or enclosures accept the FAL36040-1121?

This feed-thru, unit-mount breaker is designed for installation in Square D enclosures, switchboards, and panelboards that accommodate unit-mount F-Frame breakers. It does not plug onto an I-Line bus.

What wire sizes are compatible with the line and load lugs on this breaker?

The factory lugs accept 14 to 1/0 AWG copper (Cu) wire or 12 to 1/0 AWG aluminum (Al) wire.

Can the FAL36040-1121 be used in DC voltage systems?

Yes, in addition to its AC ratings, this thermal-magnetic breaker is rated for 250VDC applications with a 10kAIC interrupting capacity.

Are the thermal and magnetic trip points adjustable on this breaker?

No, the FAL36040-1121 features a fixed thermal (long-time) and fixed magnetic (instantaneous) trip unit. Neither the overload nor the short-circuit trip thresholds can be adjusted in the field.

How is this breaker mounted in a panel?

It is a unit-mount breaker, meaning it is secured with mounting screws or brackets and wired using feed-thru line and load lugs, rather than plugging directly into a busbar system.

Is the FAL36040-1121 part of the legacy F-Frame series?

Yes, it is a legacy Square D F-Frame (FAL) molded case circuit breaker. It is commonly used as a replacement in older Square D switchboards and enclosures that require a 40A, 3-pole unit-mount breaker.

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Reviews

5.0
Rated 5.0 out of 5 stars
Based on 39 reviews
Reviews Summary
Customers say this circuit breaker arrives in excellent condition and works as expected. The product performs flawlessly and functions reliably. Many reviews highlight fast shipping, competitive pricing, and quick delivery times. Users appreciate the availability of refurbished and obsolete models. The parts arrive well-packed and in like-new condition. Common feedback addresses excellent communication and straightforward ordering. Overall, customers report satisfaction with product quality, value, and prompt service fulfillment.
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39 reviews
  • PC
    Pierre C.
    Verified Buyer
    Reviewing
    Square D FAL3603015M - 30A 3 Pole Motor Circuit Protector
    I recommend this product
    Rated 5 out of 5 stars
    9/15/26
    Great service!!!

    Bought this to replace the faulty one. Shipped overnight and arrived at noon as promised. Works as new. Very happy with this. Awesome help from the staff. Definitely my go to place now.

    Thank you.

    Was this helpful?
  • MB
    Michael B.
    Verified Buyer
    Reviewing
    Square D FAL32030 - 30A 3 Pole Molded Case Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    8/13/26
    Great product

    This item worked as expected and is good quality. SuperBreakers did a great job with communication and delivery.

    Was this helpful?
  • ZB
    Zachary B.
    Verified Buyer
    Reviewing
    Square D FAL36040 - 40A 3 Pole Molded Case Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    7/23/26
    Perfect

    Exactly what we needed and worked flawlessly. Thanks

    Was this helpful?
  • JR
    John R.
    Verified Buyer
    Reviewing
    Square D FAL36100 - 100A 3 Pole Molded Case Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    6/29/26
    Circuit Breaker

    The breaker was in "like new" condition and well packed for shipping. Excellent value overall!

    Was this helpful?
  • RF
    Ron F.
    Verified Buyer
    Reviewing
    Square D FAL340801021 - 80A 3 Pole Molded Case Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    5/13/26
    Square D FAL340801021 - 80A 3 Pole Molded Case Circuit Breaker

    As usual SB has the best price and delivery was spot on!

    Was this helpful?