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Square D Y1B120 Molded Case Circuit Breaker

  • 20A
  • 1 Pole
  • Bolt-On
Square D Y1B120
Molded Case Circuit Breaker
Brand Square D
SKU Y1B120
Select Item Condition
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  • 20A
  • 1 Pole
  • Bolt-On

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Square D Y1B120 1 Pole Circuit Breaker

Square D Y1B120 - 20A 1 Pole Molded Case Circuit Breaker

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$66.77 No Stock

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Description

Built for commercial 277VAC lighting distribution, this single-pole 20A breaker delivers dependable thermal-magnetic overcurrent protection. It is engineered to support 277V applications in industrial facilities. Designed as a bolt-on unit, it mounts into obsolete Square D NY1B panelboards, providing a seamless fit for older infrastructure. The breaker utilizes standard load side lugs for secure wire terminations. Carrying an SWD rating, it is approved for switching fluorescent lighting loads.

Specifications

Key specifications
Brand Square D
Part Number Y1B120
Series Y1B
Amperage 20A
Poles 1
Mounting Style Bolt-On
Voltage 277VAC
Phase 1
AIC Rating 10kA @ 277VAC
Fit and installation
Frame Type Y1B
Terminal Type Lugs
For Use With Square D NY1B Panelboards
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 Padlock Attachment
Accessories Load Side Lugs Included
Standards UL 489
Approval UL
Temp Rating 40°C
Construction Features SWD Rated

Product FAQs

5 answers
What panelboards accept the Square D Y1B120 circuit breaker?

The Y1B120 is designed exclusively for installation in legacy Square D NY1B panelboards. It features a bolt-on mounting style to secure directly to the panel bus.

What type of electrical systems typically use the Y1B120 breaker?

As a single-pole 277VAC breaker, it is commonly installed in 277/480V three-phase, four-wire commercial and industrial systems to provide line-to-neutral branch circuit protection.

Can the Y1B120 be used to control fluorescent lighting?

Yes, this breaker carries an SWD (Switching Duty) rating, making it approved for switching fluorescent lighting loads in 277V commercial and industrial distribution systems.

What type of overcurrent protection does the Y1B120 provide?

It features a fixed thermal-magnetic trip unit with Long-Time and Instantaneous (LI) functions. The thermal element responds to sustained overloads, while the magnetic element trips immediately during short circuits.

How are the load-side wires terminated on the Y1B120?

The breaker is equipped with standard mechanical lugs on the load side for secure wire terminations.

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Reviews

5.0
Rated 5.0 out of 5 stars
Based on 2 reviews
Total 5 star reviews: 2 Total 4 star reviews: 0 Total 3 star reviews: 0 Total 2 star reviews: 0 Total 1 star reviews: 0
Rating
Ratings
2 reviews
  • BH
    Brian H.
    Flag of United States
    Reviewing
    Square D Y1B120 - 20A 1 Pole Molded Case Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    7/6/22
    works great, superb packaging

    works great, superb packaging

  • CF
    Charles F.
    Flag of United States
    Reviewing
    Square D Y1B120 - 20A 1 Pole Molded Case Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    2/6/18
    Breaker

    Easy to order and was here in no time