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Siemens BQ1B045 Molded Case Circuit Breaker
- 45A
- 1 Pole
- Bolt-On
Siemens
BQ1B045
Molded Case Circuit Breaker
Brand
Siemens
SKU
BQ1B045
Quantity
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Siemens BQ1B045 - 45A 1 Pole Molded Case Circuit Breaker
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Description
Built for commercial and industrial power distribution, the Siemens BQ1B045 is a 45A, 1-pole molded case circuit breaker. It delivers standard thermal-magnetic trip functionality to protect branch circuits against overloads and short circuits. Designed with a bolt-on mounting style, this unit installs into Siemens P1, P2, and P3 panelboards. Rated for 10kAIC at 120VAC, this BQ series breaker is both HACR and HID lighting rated, making it versatile for specialized commercial loads.Specifications
| Brand | Siemens |
|---|---|
| Part Number | BQ1B045 |
| Series | BQ |
| Amperage | 45A |
| Poles | 1 |
| Mounting Style | Bolt-On |
| Voltage | 120VAC |
| Phase | 1 |
| AIC Rating | 10kA @ 120VAC |
| Frame Type | BQ |
|---|---|
| Terminal Type | Lugs |
| For Use With | Siemens P1, P2, P3 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) |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed |
| Available Options | Padlock Attachment, Handle Tie |
|---|---|
| Accessories | Load Side Lugs |
| Standards | CSA C22.2 No. 5, HACR Rated, HID, UL 489 |
| Approval | CSA, HACR, HID, UL |
| Temp Rating | 40C |
Product FAQs
7 answersWhich panelboards are compatible with the BQ1B045 circuit breaker?
This bolt-on breaker is designed for installation in Siemens P1, P2, and P3 panelboards.
Is there a plug-in equivalent for the BQ1B045?
Yes, the Siemens Q145 is the plug-in equivalent for this 45A breaker, designed for use in standard Q or QP series load centers.
Does the BQ1B045 carry a HACR rating?
Yes, this breaker is HACR rated, making it suitable for use with heating, air conditioning, and refrigeration equipment.
Is this 45A breaker rated for high-intensity discharge (HID) lighting?
Yes, the BQ1B045 is HID rated, allowing it to safely switch high-intensity discharge lighting loads.
What wire sizes and materials are accepted by the lugs on the BQ1B045?
The factory-installed lugs accommodate 8 to 1 AWG copper conductors or 6 to 1/0 AWG aluminum conductors.
How does the BQ1B045 mount into the panelboard?
This is a bolt-on circuit breaker that secures directly to the panelboard bus using a bolted connection, providing a secure contact for commercial applications.
Are the trip settings on the BQ1B045 adjustable?
No, this thermal magnetic breaker features fixed long-time and instantaneous trip functions.
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Parcel shipments with item value over $99 qualify for free economy shipping within the continental US. Please call to confirm special handling instructions. We do not charge a handling fee or require a minimum amount on any order. SuperBreakers does not ship on customer accounts.
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All International orders require a $1,000 minimum order threshold. Due to the special nature of these shipments, we require that these be placed with a SuperBreakers representative. Additional shipping and instructions will apply. All International Orders are Non-Cancel and Non-Refundable.
Reviews
Review summary
Customers rate this product 4.9 out of 5 based on 73 reviews.
Reviews Summary
Generated by AI from 67 most recent customer reviews
Last updated 6/3/26
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.
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Rating
73 reviews
- HSHector S.Verified BuyerReviewingSiemens BQ3B100H - 100A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars9/27/26Perfect replacement
Fit perfectly and good price
- AFAnthony F.Verified BuyerReviewingSiemens BQ2B020 - 20A 2 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars9/25/26works as expected
works as expected
- MSMike S.Verified BuyerReviewingEaton / Cutler-Hammer BQ250250 - 50/50A Quadplex Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars8/12/26Electrical company
Breaker worked awesome thank you very much
- PEPhilip E.Verified BuyerReviewingSiemens BQ3B020 - 20A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars8/10/26Siemens BQ3B020
The breaker arrived as described and on time. It works as expected. I will order from SuperBreakers again in the future without hesitation.
- PLPaul L.Verified BuyerReviewingSiemens BQ1B020 - 20A 1 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars7/23/26Breaker
Quick shipping. Exact fit.