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Siemens FD63B125 Molded Case Circuit Breaker
- 125A
- 3 Pole
- Unit Mount
Siemens
FD63B125
Molded Case Circuit Breaker
Brand
Siemens
SKU
FD63B125
Quantity
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Siemens FD63B125 - 125A 3 Pole Molded Case Circuit Breaker
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Siemens FD63B125 - 125A 3 Pole Molded Case Circuit Breaker
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Quantity
| Brand | Siemens |
|---|---|
| Part Number | FD63B125 |
| Series | FD6 |
| Amperage | 125A |
| Poles | 3 |
| Mounting Style | Unit Mount |
| Voltage | 240VAC, 480VAC, 600VAC, 500VDC |
| Phase | 3 |
| AIC Rating | 65kA @ 240VAC, 35kA @ 480VAC, 22kA @ 600VAC, 18kA @ 500VDC |
| Terminal Type | Lugs |
|---|---|
| For Use With | Siemens P1 (Subfeed), P2, P3, P4, P5 Panelboards, Switchboards, Motor Control Centers |
| Wire Gauge | 6 AWG - 350 kcmil (Cu), 4 AWG - 350 kcmil (Al) |
| Max Wire | 350 kcmil |
| Min Wire | 6 AWG (Cu), 4 AWG (Al) |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed Thermal, Adjustable Magnetic |
| Available Options | Shunt Trip, Undervoltage Release, Auxiliary Switch, Alarm Switch |
|---|---|
| Accessories | Line and Load Lugs Included, TA1FD350A |
| Standards | CSA C22.2 No. 5, IEC 60947-2, NEMA AB 1, UL 489 |
| Approval | CE, CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Interchangeable Trip Unit |
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Siemens FD63B125 - 125A 3 Pole Molded Case Circuit Breaker
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| Brand | Siemens |
|---|---|
| Part Number | FD63B125 |
| Series | FD6 |
| Amperage | 125A |
| Poles | 3 |
| Mounting Style | Unit Mount |
| Voltage | 240VAC, 480VAC, 600VAC, 500VDC |
| Phase | 3 |
| AIC Rating | 65kA @ 240VAC, 35kA @ 480VAC, 22kA @ 600VAC, 18kA @ 500VDC |
| Terminal Type | Lugs |
|---|---|
| For Use With | Siemens P1 (Subfeed), P2, P3, P4, P5 Panelboards, Switchboards, Motor Control Centers |
| Wire Gauge | 6 AWG - 350 kcmil (Cu), 4 AWG - 350 kcmil (Al) |
| Max Wire | 350 kcmil |
| Min Wire | 6 AWG (Cu), 4 AWG (Al) |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed Thermal, Adjustable Magnetic |
| Available Options | Shunt Trip, Undervoltage Release, Auxiliary Switch, Alarm Switch |
|---|---|
| Accessories | Line and Load Lugs Included, TA1FD350A |
| Standards | CSA C22.2 No. 5, IEC 60947-2, NEMA AB 1, UL 489 |
| Approval | CE, CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Interchangeable Trip Unit |
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Description
Designed for integration into Siemens P1 subfeed, P2, P3, P4, and P5 panelboards, this 125-amp molded case circuit breaker handles rigorous industrial loads. The FD frame unit features an interchangeable trip mechanism with fixed thermal and adjustable magnetic settings for customized LI protection. It includes factory-installed TA1FD350A line and load lugs for immediate wiring. Rated for 35kAIC at 480VAC, it provides dependable fault clearing for motor control centers and switchboards.Specifications
| Brand | Siemens |
|---|---|
| Part Number | FD63B125 |
| Series | FD6 |
| Amperage | 125A |
| Poles | 3 |
| Mounting Style | Unit Mount |
| Voltage | 240VAC, 480VAC, 600VAC, 500VDC |
| Phase | 3 |
| AIC Rating | 65kA @ 240VAC, 35kA @ 480VAC, 22kA @ 600VAC, 18kA @ 500VDC |
| Terminal Type | Lugs |
|---|---|
| For Use With | Siemens P1 (Subfeed), P2, P3, P4, P5 Panelboards, Switchboards, Motor Control Centers |
| Wire Gauge | 6 AWG - 350 kcmil (Cu), 4 AWG - 350 kcmil (Al) |
| Max Wire | 350 kcmil |
| Min Wire | 6 AWG (Cu), 4 AWG (Al) |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed Thermal, Adjustable Magnetic |
| Available Options | Shunt Trip, Undervoltage Release, Auxiliary Switch, Alarm Switch |
|---|---|
| Accessories | Line and Load Lugs Included, TA1FD350A |
| Standards | CSA C22.2 No. 5, IEC 60947-2, NEMA AB 1, UL 489 |
| Approval | CE, CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Interchangeable Trip Unit |
Product FAQs
7 answersWhat is the difference between the Siemens FD63B125 and the FXD63B125?
The FD63B125 features an interchangeable trip unit, allowing the trip mechanism to be replaced or upgraded in the field. The FXD63B125 has a factory-sealed, non-interchangeable trip unit. Both share the same physical dimensions, amperage, and interrupting ratings.
Can the FD63B125 circuit breaker be reverse fed?
No. According to UL 489 standards, circuit breakers with interchangeable trip units like the FD63B125 cannot be reverse fed. If your application requires reverse feeding, you must use the non-interchangeable FXD63B125 version.
What is the magnetic trip adjustment range for this 125A breaker?
The instantaneous magnetic trip on the FD63B125 is adjustable from 900 Amps to 1500 Amps. The thermal overload protection remains fixed at 125 Amps.
Which Siemens panelboards are compatible with the FD63B125?
This breaker is designed for use in Siemens P1 (as a subfeed breaker), P2, P3, P4, and P5 panelboards, as well as compatible switchboards and motor control centers.
What replacement lugs are compatible with the FD63B125?
The standard line and load lug kit for this breaker is part number TA1FD350A. These aluminum body lugs accept 6 AWG to 350 kcmil copper wire or 4 AWG to 350 kcmil aluminum wire.
Will this breaker replace an older I-T-E FD63B125?
Yes. Siemens acquired I-T-E and continued manufacturing the Sentron series. A modern Siemens FD63B125 is a direct replacement for an older I-T-E breaker with the exact same catalog number.
What are the individual frame and trip unit part numbers for the FD63B125?
The FD63B125 is a complete, assembled breaker. If you are building it from components, it consists of an FD63F250 frame and an FD63T125 interchangeable trip unit.
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