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Siemens B240 Miniature Circuit Breaker
- 40A
- 2 Pole
- Bolt-On
Siemens
B240
Miniature Circuit Breaker
Brand
Siemens
SKU
B240
Quantity
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Siemens B240 - 40A 2 Pole Miniature Circuit Breaker
Re-Certified
Quantity
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Siemens B240 - 40A 2 Pole Miniature Circuit Breaker
New
Quantity
| Brand | Siemens |
|---|---|
| Part Number | B240 |
| Series | B |
| Amperage | 40A |
| 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 |
| Available Options | Padlock Attachment, Handle Tie |
|---|---|
| Accessories | Load Side Lugs Included |
| Standards | CSA C22.2 No. 5, UL 489 |
| Approval | CSA, HACR, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated |
Sold out
Quantity
Siemens B240 - 40A 2 Pole Miniature Circuit Breaker
Re-Certified
Quantity
| Brand | Siemens |
|---|---|
| Part Number | B240-R |
| Series | B |
| Amperage | 40A |
| 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 |
| Available Options | Padlock Attachment, Handle Tie |
|---|---|
| Accessories | Load Side Lugs Included |
| Standards | CSA C22.2 No. 5, UL 489 |
| Approval | CSA, HACR, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated |
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Description
Designed for reliable power distribution, the Siemens B240 is a 40-amp, 2-pole miniature circuit breaker. It utilizes thermal-magnetic technology to safeguard commercial circuits at 120/240VAC. The breaker installs into Siemens P1 through P5 panelboards via a standard bolt-on connection. It provides a functional substitute for BAB2040, QOB240, and THQB2140 configurations. With a 10kAIC rating, this component is fully HACR rated for HVAC loads.Specifications
| Brand | Siemens |
|---|---|
| Part Number | B240-R |
| Series | B |
| Amperage | 40A |
| 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 |
| Available Options | Padlock Attachment, Handle Tie |
|---|---|
| Accessories | Load Side Lugs Included |
| Standards | CSA C22.2 No. 5, UL 489 |
| Approval | CSA, HACR, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated |
Product FAQs
8 answersWhat panelboards are compatible with the B240?
The Siemens B240 is designed for bolt-on installation in Siemens P1, P2, P3, P4, and P5 commercial panelboards. It also fits legacy ITE distribution panels that accept Type BL or B-frame bolt-on breakers.
Is the Siemens B240 the same as the BL240?
Yes. The B240 is the catalog number for the 40-amp, 2-pole Type BL circuit breaker. Both part numbers refer to the exact same bolt-on thermal-magnetic breaker used in Siemens and legacy ITE panelboards.
Can I use this breaker to supply HVAC or motor loads?
Yes. This Type BL circuit breaker is fully HACR rated, meaning it is UL approved to safely protect heating, air conditioning, and refrigeration equipment loads.
Is the 10kAIC interrupting rating sufficient for commercial panelboards?
A 10kAIC rating is standard for many branch circuits, but you must verify the available fault current at your specific panelboard. If the panel requires a higher interrupting rating, you must upgrade to a Type BLH (22kAIC) or Type HBL (65kAIC) breaker to maintain code compliance.
Does the B240 provide common trip protection?
Yes. As a factory-assembled 2-pole breaker, the B240 features an internal common trip mechanism. If one pole experiences an overcurrent or short circuit, both poles trip simultaneously to safely disconnect the entire 240V circuit.
What kind of protection does the LI trip function provide?
The LI designation indicates thermal-magnetic protection. The L stands for long-time protection, utilizing a thermal bimetal element to guard against gradual overloads. The I stands for instantaneous protection, which uses a magnetic coil to trip the breaker immediately during a short circuit.
Why does this panelboard breaker use a bolt-on connection?
Bolt-on connections use screws to firmly attach the breaker directly to the panelboard bus bars. This provides a highly secure mechanical connection that will not loosen over time due to vibration, thermal cycling, or short-circuit forces, which is essential in commercial and industrial settings.
How much mounting space does the B240 require in the panel?
The B240 uses a standard 1-inch per pole frame size. Since it is a 2-pole device, it requires two adjacent 1-inch positions, occupying a total of 2 inches of bus space in your panelboard.
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