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Siemens BQ2B050 Molded Case Circuit Breaker

  • 50A
  • 2 Pole
  • Bolt-On
Siemens BQ2B050
Molded Case Circuit Breaker
Brand Siemens
SKU BQ2B050
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  • 50A
  • 2 Pole
  • Bolt-On

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Siemens BQ2B050 - 50A 2 Pole Molded Case Circuit Breaker

Siemens BQ2B050 - 50A 2 Pole Molded Case Circuit Breaker

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$14.03 No Stock

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Description

Part of the Siemens BQ family, this 50A molded case circuit breaker delivers long-time and instantaneous trip functions for maximum current limiting protection. The 2-pole device is rated for 120/240VAC systems and features a 10kAIC interrupting capacity. It mounts securely into standard Siemens panelboards using a bolt-on connection, ensuring a stable fit for commercial and industrial environments. The breaker includes load side lugs and carries a HACR rating for HVAC applications.

Specifications

Key specifications
Brand Siemens
Part Number BQ2B050-R
Series BQ
Amperage 50A
Poles 2
Mounting Style Bolt-On
Voltage 120/240VAC
Phase 1
AIC Rating 10kA @ 120/240VAC
Fit and installation
Frame Type BQ
Terminal Type Lugs
For Use With Siemens Panelboards
Wire Gauge 8-6 AWG (Cu), 8-4 AWG (Al)
Max Wire 6 AWG (Cu), 4 AWG (Al)
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 Shunt Trip, Auxiliary Switch, Alarm Switch, Padlock Attachment
Accessories Load Side Lugs
Standards CSA C22.2 No. 5, HACR Rated, NEMA AB 1, UL 489
Approval CSA, HACR, UL
Temp Rating 40C

Product FAQs

7 answers
Which panelboards are compatible with the Siemens BQ2B050?

This BQ frame bolt-on breaker is designed for commercial Siemens panelboards including P1, P2, P3, S1, and S2 series, as well as legacy ITE and Gould equivalent panels that accept bolt-on branch breakers.

Will the BQ2B050 fit into a standard plug-on residential load center?

No. This is a bolt-on breaker intended for commercial panelboards equipped with threaded busbars. It will not attach to residential load centers that require plug-on QP style breakers.

What is the difference between Siemens BQ, BQH, and HBQ series breakers?

The difference lies in their maximum short circuit interrupting ratings. The standard BQ series is rated at 10kAIC at 120/240VAC. The BQH series provides a 22kAIC rating, and the HBQ series offers a 65kAIC rating. All three series share the same physical footprint and panelboard compatibility.

Is the Siemens BQ2B050 a direct replacement for legacy ITE BQ breakers?

Yes. Siemens acquired the ITE electrical distribution brand. Current Siemens BQ series breakers are direct, UL approved replacements for older ITE, Gould, and Bulldog breakers sharing the exact same catalog numbers.

How is the line side of the BQ2B050 breaker connected to the panel?

The breaker fastens directly to the panelboard busbar using standard mounting screws. This bolt-on design creates a secure mechanical and electrical connection that resists vibration in commercial and industrial environments.

Is the Siemens BQ2B050 suitable for reverse feed applications?

Yes. Siemens BQ frame circuit breakers feature non-interchangeable thermal magnetic trip units and are approved for reverse feed installations under UL 489 standards.

Is the BQ2B050 HACR rated for HVAC motor loads?

Yes. This circuit breaker carries a HACR rating, making it code compliant for protecting heating, air conditioning, and refrigeration equipment circuits.

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Reviews

4.9
Rated 4.9 out of 5 stars
Based on 73 reviews
Reviews Summary
Customers say these breakers arrive quickly and fit perfectly for their electrical needs. Fast shipping and competitive pricing are frequently mentioned, with many users appreciating the availability of hard-to-find and older-style breakers. The products are well-packaged and arrive in good condition. Most customers report successful installations and reliable performance. A few note missing items from orders or concerns about product condition, though the majority express satisfaction with their purchases and indicate they would order again.
Rating
Ratings
73 reviews
  • HS
    Hector S.
    Verified Buyer
    Reviewing
    Siemens BQ3B100H - 100A 3 Pole Molded Case Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    9/27/26
    Perfect replacement

    Fit perfectly and good price

  • AF
    Anthony F.
    Verified Buyer
    Reviewing
    Siemens BQ2B020 - 20A 2 Pole Molded Case Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    9/25/26
    works as expected

    works as expected

  • MS
    Mike S.
    Verified Buyer
    Reviewing
    Eaton / Cutler-Hammer BQ250250 - 50/50A Quadplex Miniature Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    8/12/26
    Electrical company

    Breaker worked awesome thank you very much

  • PE
    Philip E.
    Verified Buyer
    Reviewing
    Siemens BQ3B020 - 20A 3 Pole Molded Case Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    8/10/26
    Siemens BQ3B020

    The breaker arrived as described and on time. It works as expected. I will order from SuperBreakers again in the future without hesitation.

  • PL
    Paul L.
    Verified Buyer
    Reviewing
    Siemens BQ1B020 - 20A 1 Pole Molded Case Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    7/23/26
    Breaker

    Quick shipping. Exact fit.