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Siemens BQ3B100 Molded Case Circuit Breaker

  • 100A
  • 3 Pole
  • Bolt-On
Siemens BQ3B100
Molded Case Circuit Breaker
Brand Siemens
SKU BQ3B100
Select Item Condition
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  • 100A
  • 3 Pole
  • Bolt-On

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Siemens BQ3B100 - 100A 3 Pole Molded Case Circuit Breaker

Siemens BQ3B100 - 100A 3 Pole Molded Case Circuit Breaker

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$135.00 No Stock

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Description

Part of the BQ series, this 100A three-pole molded case circuit breaker delivers standard commercial overcurrent protection. It features a thermal-magnetic trip unit configured for 240VAC systems. Designed for seamless integration, the unit installs into Siemens P1 panelboards and legacy ITE enclosures. The bolt-on mounting style ensures a secure mechanical connection for demanding environments. Rated at 10kA interrupting capacity, this HACR-certified component accepts 8-1 AWG copper wire.

Specifications

Key specifications
Brand Siemens
Part Number BQ3B100-R
Series BQ
Amperage 100A
Poles 3
Mounting Style Bolt-On
Voltage 240VAC
Phase 3
AIC Rating 10kA @ 240VAC
Fit and installation
Frame Type BQ
Terminal Type Lugs
For Use With Siemens P1 Panelboards, ITE Panelboards
Wire Gauge 8-1 AWG (Cu), 6-1/0 AWG (Al)
Max Wire 1 AWG (Cu), 1/0 AWG (Al)
Min Wire 8 AWG (Cu), 6 AWG (Al)
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, UL 489
Approval CSA, HACR, UL
Temp Rating 40C

Product FAQs

6 answers
Can I use this Siemens BQ3B100 to replace an older ITE BQ3B100 breaker?

Yes. Since Siemens acquired ITE, current BQ series breakers are manufactured to the same physical dimensions and specifications. The Siemens BQ3B100 serves as a direct, backward-compatible replacement for legacy ITE units.

Which commercial panelboards accept the BQ3B100 circuit breaker?

This unit features a non-interchangeable bolt-on design intended specifically for secure mounting to the busbars in Siemens P1 panelboards, as well as older ITE distribution enclosures.

What does the LI trip function indicate on this molded case breaker?

The LI code means this thermal-magnetic trip unit provides Long-Time (L) overload protection and Instantaneous (I) short-circuit protection. These fixed settings provide reliable standard commercial overcurrent protection.

Are there equivalent 100A 3-pole BQ breakers with higher interrupting ratings?

Yes. If your electrical system requires a higher fault current rating than the standard 10kA provided by the BQ3B100, Siemens offers the BQH3B100 rated at 22kA, and the HBQ3B100 rated at 65kA at 240VAC.

Is the Siemens BQ3B100 suitable for HVAC equipment protection?

Yes, this breaker is HACR rated. This certification verifies that it has been tested to safely handle the specific inrush currents and operational demands of commercial heating, air conditioning, and refrigeration motor loads.

How are branch circuit conductors connected to the BQ3B100?

The breaker comes equipped with factory-installed load lugs on the output side. These mechanical lugs are dual-rated for bare copper and aluminum wire, while the line side bolts directly to the panelboard bus for a secure mechanical connection.

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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.