Designed to protect commercial branch circuits, the Siemens LGB3K015B is a 3-pole, 15A molded case circuit breaker from the Sentron family. It offers a high interrupting capacity of 65 kAIC at 480Y/277V and 25 kAIC at 600Y/347V. The breaker mounts securely into Siemens P1, P2, and P3 panelboards using a standard bolt-on configuration. While this GB-frame model is highly reliable, Siemens has designated the 3VA5195-6ED31-0AA0 as its official replacement for future panel upgrades.
Which panelboards are compatible with the Siemens LGB3K015B circuit breaker?
The LGB3K015B is designed for bolt-on installation in Siemens P1, P2, and P3 series panelboards. It is not compatible with standard plug-on residential load centers.
What wire sizes and materials are accepted by the lugs on the LGB3K015B?
The factory lugs on this breaker accept 14-6 AWG copper (Cu) wire or 12-6 AWG aluminum (Al) wire.
Can the LGB3K015B be used in DC voltage applications?
Yes, this breaker is rated for use in DC systems up to 125/250VDC, providing an interrupting capacity of 14kAIC for direct current applications.
How does the LGB3K015B mount into the panelboard?
This is a bolt-on circuit breaker. It requires a bolted connection directly to the panelboard bus, providing a secure, vibration-resistant installation suitable for commercial and industrial environments.
What is the difference between the Siemens LGB, NGB, and HGB frame breakers?
While they share the same physical GB frame size and panelboard compatibility, they differ in interrupting capacity. The LGB series offers the highest interrupting rating (65kAIC at 480V), compared to the standard NGB and mid-tier HGB breakers.
Does the LGB3K015B feature adjustable trip settings?
No, this breaker uses a fixed thermal and fixed magnetic (LI) trip unit. The long-time and instantaneous trip functions are factory set and cannot be adjusted in the field.
What is the maximum frame rating for the Siemens LGB breaker family?
The LGB3K015B belongs to the Siemens GB frame family, which supports a maximum frame rating of 125A.
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Reviews
Review summary
Customers rate this product 5.0 out of 5 based on 1 review.
Siemens LGB3B045B - 45A 3 Pole Molded Case Circuit Breaker
I recommend this product
Rated 5 out of 5 stars
9/27/26
Siemens 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.