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Siemens B245 Molded Case Circuit Breaker
- 45A
- 2 Pole
- Bolt-On
Siemens
B245
Molded Case Circuit Breaker
Brand
Siemens
SKU
B245
Quantity
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Siemens B245 - 45A 2 Pole Molded Case Circuit Breaker
New
Quantity
Quantity
Siemens B245 - 45A 2 Pole Molded Case Circuit Breaker
New
Quantity
| Brand | Siemens |
|---|---|
| Part Number | B245 |
| Series | BL |
| Amperage | 45A |
| Poles | 2 |
| Mounting Style | Bolt-On |
| Voltage | 120/240VAC |
| Phase | 1 |
| AIC Rating | 10kA @ 120/240VAC |
| Frame Type | B |
|---|---|
| Terminal Type | Lugs |
| For Use With | Siemens P1, P2, P3, P4, P5 Panelboards |
| Wire Gauge | 8-6 AWG (Cu), 8-4 AWG (Al) |
| Max Wire | 6 AWG (Cu), 4 AWG (Al) |
| Min Wire | 8 AWG |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed Thermal, Fixed Magnetic |
| Available Options | Shunt Trip, Auxiliary Switch, Alarm Switch, Padlock Attachment |
|---|---|
| Standards | CSA C22.2 No. 5, UL 489, HACR Rated |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated |
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Siemens B245 - 45A 2 Pole Molded Case Circuit Breaker
Re-Certified
Quantity
| Brand | Siemens |
|---|---|
| Part Number | B245-R |
| Series | BL |
| Amperage | 45A |
| Poles | 2 |
| Mounting Style | Bolt-On |
| Voltage | 120/240VAC |
| Phase | 1 |
| AIC Rating | 10kA @ 120/240VAC |
| Frame Type | B |
|---|---|
| Terminal Type | Lugs |
| For Use With | Siemens P1, P2, P3, P4, P5 Panelboards |
| Wire Gauge | 8-6 AWG (Cu), 8-4 AWG (Al) |
| Max Wire | 6 AWG (Cu), 4 AWG (Al) |
| Min Wire | 8 AWG |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed Thermal, Fixed Magnetic |
| Available Options | Shunt Trip, Auxiliary Switch, Alarm Switch, Padlock Attachment |
|---|---|
| Standards | CSA C22.2 No. 5, UL 489, HACR Rated |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated |
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Description
Built for commercial and industrial power distribution, the Siemens B245 delivers reliable 2-pole, 45A circuit protection. It mounts into Siemens P1, P2, P3, P4, and P5 panelboards, utilizing a secure bolted connection to ensure stable performance in high-vibration environments. Rated for 10 kAIC at 120/240VAC, this BL frame breaker utilizes standard thermal-magnetic trip technology for dependable overload and short-circuit defense. It accepts 8-6 AWG copper or 8-4 AWG aluminum wire.Specifications
| Brand | Siemens |
|---|---|
| Part Number | B245 |
| Series | BL |
| Amperage | 45A |
| Poles | 2 |
| Mounting Style | Bolt-On |
| Voltage | 120/240VAC |
| Phase | 1 |
| AIC Rating | 10kA @ 120/240VAC |
| Frame Type | B |
|---|---|
| Terminal Type | Lugs |
| For Use With | Siemens P1, P2, P3, P4, P5 Panelboards |
| Wire Gauge | 8-6 AWG (Cu), 8-4 AWG (Al) |
| Max Wire | 6 AWG (Cu), 4 AWG (Al) |
| Min Wire | 8 AWG |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed Thermal, Fixed Magnetic |
| Available Options | Shunt Trip, Auxiliary Switch, Alarm Switch, Padlock Attachment |
|---|---|
| Standards | CSA C22.2 No. 5, UL 489, HACR Rated |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated |
Product FAQs
7 answersWhat panelboards are compatible with the Siemens B245 circuit breaker?
The B245 is a bolt-on breaker designed for use in Siemens P1, P2, P3, P4, and P5 series commercial panelboards.
Can I install the B245 in a standard Siemens residential load center?
No. The B245 is a BL series bolt-on breaker intended for commercial panelboards. Standard Siemens residential load centers require plug-on breakers, such as the QP series.
What wire sizes do the load side lugs on the B245 accept?
The included lugs accept 8 to 6 AWG copper wire or 8 to 4 AWG aluminum wire.
Are there versions of this 45A breaker with a higher interrupting rating?
Yes. If your system requires a higher fault current rating, you can use the B245H for 22kAIC or the B245HH for 65kAIC at 120/240VAC.
Is the Siemens B245 suitable for use with heating and cooling equipment?
Yes, this breaker is HACR rated, making it suitable for protecting heating, air conditioning, and refrigeration circuits.
How does the B245 connect to the panelboard bus?
It utilizes a bolt-on connection, which provides a secure, vibration-resistant mechanical fastening to the panelboard bus bars.
What type of trip protection does the B245 provide?
It features a fixed thermal-magnetic trip unit that provides both long-time overload protection and instantaneous short-circuit protection.
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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 5.0 out of 5 based on 35 reviews.
Total 5 star reviews: 34 Total 4 star reviews: 1 Total 3 star reviews: 0 Total 2 star reviews: 0 Total 1 star reviews: 0
Reviews Summary
Generated by AI from 66 most recent customer reviews
Last updated 8/15/25
Customers say these circuit breakers meet their specifications and perform as expected. Many reviews highlight the quick delivery times and competitive pricing. Frequent comments address the reliable product quality and ease of installation. The ordering process receives praise for its simplicity, with users noting consistent product availability.
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Rating
35 reviews
- TSTom S.Verified BuyerReviewingSiemens B3100 3 Pole Circuit BreakerI recommend this productRated 5 out of 5 stars8/3/26Superbreakers is our go to!
Great prices, great service and quick delivery.
- MGMaggie G.Verified BuyerReviewingSiemens B250 - 50A 2 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars6/24/26Great Service
Came in great condition and in an incredibly timely manner. Will continue superbreakers for all of my orders in the future!
- DBDonnie B.Verified BuyerReviewingSiemens B115 - 15A 1 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars6/11/26New Breaker
Awesome breaker & Superbreakers is a awesome company!
- BLBrian L.Verified BuyerReviewingSiemens B120 - 20A 1 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars6/4/26Brian
Works great
- JFJoseph F.Verified BuyerReviewingSiemens B120 - 20A 1 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars3/23/26Great value
It was a great value