Siemens LGB3K045B Molded Case Circuit Breaker
- 45A
- 3 Pole
- Bolt-On
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Siemens LGB3K045B - 45A 3 Pole Molded Case Circuit Breaker
New
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Description
Designed to handle demanding electrical loads, the Siemens LGB3K045B is a 45A, 3-pole MCCB. As part of the Sentron GB frame series, it utilizes fixed thermal-magnetic trip units. This bolt-on breaker installs into Siemens P1, P2, and P3 panelboards. For modern upgrades, it is replaced by the 3VA4145-6ED34-0AA0, requiring an adapter kit. Rated for 65 kAIC at 480Y/277V, it offers exceptional fault-clearing capabilities. The unit is HACR and HID rated for versatile commercial applications.Specifications
| Brand | Siemens |
|---|---|
| Series | LGB |
| Amperage | 45A |
| Poles | 3 |
| Mounting Style | Bolt-On |
| Voltage | 240VAC, 480Y/277VAC, 600Y/347VAC, 125/250VDC |
| Phase | 3 |
| AIC Rating | 100kA @ 240VAC, 65kA @ 480Y/277VAC, 25kA @ 600Y/347VAC, 14kA @ 125/250VDC |
| Frame Type | LGB |
|---|---|
| Terminal Type | Lugs |
| For Use With | Siemens P1, P2, P3 Panelboards |
| Wire Gauge | 8-1/0 AWG (Cu), 8-2/0 AWG (Al) |
| Max Wire | 1/0 AWG (Cu), 2/0 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 |
|---|---|
| Accessories | Load Side Lugs |
| Standards | CSA C22.2 No. 5, UL 489 |
| Approval | CE, CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, HID Rated, Trip-Free Mechanism |
Product FAQs
6 answersWhat panelboards are compatible with the LGB3K045B?
This bolt-on circuit breaker is designed specifically for branch circuit applications in Siemens P1, P2, and P3 panelboards.
What wire sizes and materials are accepted by the lugs on this breaker?
The factory-installed load side lugs accept 8 to 1/0 AWG copper wire or 8 to 2/0 AWG aluminum wire. Always ensure proper torque specifications are followed during installation.
Is the trip unit on the LGB3K045B adjustable?
No, this breaker features a fixed thermal and fixed magnetic trip unit. It provides standard long-time and instantaneous (LI) protection without adjustable dials.
Has the LGB3K045B been discontinued by Siemens?
Yes, Siemens has phased out the legacy LGB frame series and designated the 3VA41 series as its modern successor. However, the LGB3K045B is still commonly sourced to replace existing breakers in older panelboards.
Can the LGB3K045B be used in direct current (DC) systems?
Yes, in addition to its standard AC ratings, this breaker is rated for DC applications with an interrupting capacity of 14kA at 125/250VDC.
Does this breaker provide ground fault or arc fault protection?
No, the LGB3K045B is a standard thermal-magnetic breaker providing overload and short-circuit protection. It does not include GFCI or AFCI capabilities.
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Reviews
Review summary
Customers rate this product 5.0 out of 5 based on 1 review.
- RSRon S.Verified BuyerReviewingSiemens LGB3B045B - 45A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars9/27/26Siemens Breaker
The breaker was exactly what I needed, and it came within a couple days. The price was in line of what it should’ve been. This was my third purchase from Super Breakers. I will definitely use them again in the future.