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Siemens B145 Molded Case Circuit Breaker
- 45A
- 1 Pole
- Bolt-On
Siemens
B145
Molded Case Circuit Breaker
Brand
Siemens
SKU
B145
Quantity
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Siemens B145 - 45A 1 Pole Molded Case Circuit Breaker
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Description
Built for commercial and industrial applications, the Siemens B145 provides reliable thermal-magnetic overcurrent protection. This 45-amp, single-pole molded case circuit breaker delivers a standard 10kAIC interrupting rating at 120/240VAC. Designed for seamless integration, it installs into Siemens P1, P2, P3, P4, and P5 panelboards via a sturdy bolt-on connection. The HACR-rated unit features a trip-free mechanism, non-interchangeable trip unit, and supports reverse feed configurations.Specifications
| Brand | Siemens |
|---|---|
| Part Number | B145 |
| Series | B |
| Amperage | 45A |
| Poles | 1 |
| 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 |
| Available Options | Shunt Trip, Auxiliary Switch, Alarm Switch, Padlock Attachment, Handle Tie |
|---|---|
| Accessories | Load Side Lugs Included |
| Standards | CSA C22.2 No. 5, HACR, UL 489 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Non-Interchangeable Trip, Reverse Feed, Trip-Free Mechanism |
Product FAQs
7 answersWhich Siemens panelboards accept the B145 circuit breaker?
The B145 is a bolt-on breaker designed specifically for Siemens P1, P2, P3, P4, and P5 commercial panelboards. It is not compatible with standard plug-on load centers.
What are the acceptable wire gauges for the B145 terminal lugs?
The integrated lugs accept 8 to 6 AWG copper conductors or 8 to 4 AWG aluminum conductors. Ensure proper torque specifications are followed during installation.
Is the Siemens B145 suitable for 277V lighting circuits?
No, this breaker is rated for a maximum of 120/240VAC. For 277VAC applications, a different breaker series such as the Siemens BQD is required.
What frame family does the B145 belong to?
The B145 is part of the Siemens B frame family, which is widely known in the industry as the BL series of miniature bolt-on circuit breakers.
What type of protection does the thermal-magnetic trip unit provide?
The fixed thermal-magnetic trip unit delivers long-time (L) protection against sustained overloads and instantaneous (I) protection against short circuits.
How is the B145 secured to the panelboard bus?
It features a bolt-on connection that fastens directly to the busbars of compatible Siemens P-series panelboards, providing a secure and vibration-resistant mechanical connection.
Is the Siemens B145 suitable for HVAC equipment?
Yes, this breaker is HACR rated, meaning it is approved for use with heating, air conditioning, and refrigeration equipment.
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