Engineered for commercial and industrial power systems, the Siemens LGB2K100B is a 2-pole molded case circuit breaker. It provides reliable thermal-magnetic protection for branch circuits and feeders. This bolt-on unit mounts into Siemens P1, P2, and P3 panelboards. For modern upgrades, it is replaced by the 3VA5110-6ED21-0AA0, which requires a separate mounting strap kit for P1 panels. Rated at 65kAIC at 480Y/277V, it features a low tab design and HACR certification for HVAC applications.
HACR Rated, High Interrupting Capacity, Reverse Feed
Product FAQs
7 answers
Which panelboards are compatible with the LGB2K100B circuit breaker?
This bolt-on molded case circuit breaker is designed for use in Siemens P1, P2, and P3 panelboards.
Can the LGB2K100B be installed in standard residential load centers?
No, this is a bolt-on breaker intended for commercial and industrial Siemens P1, P2, and P3 panelboards. It is not compatible with standard plug-on residential load centers.
What wire sizes and materials are accepted by the LGB2K100B lugs?
The factory-installed lugs accept 8 to 1/0 AWG copper wire or 8 to 2/0 AWG aluminum wire.
Can the LGB2K100B be used in DC electrical systems?
Yes, in addition to AC applications, this breaker is rated for 125/250VDC systems, providing a 14kAIC interrupting capacity for direct current equipment.
Does the LGB2K100B allow for field-adjustable trip settings?
No, this thermal-magnetic breaker has fixed thermal and fixed magnetic trip elements for its long-time and instantaneous (LI) protection functions.
Does the LGB2K100B provide ground fault or arc fault protection?
No, this is a standard thermal-magnetic circuit breaker providing overload and short-circuit protection. It does not include GFCI or AFCI functionality.
What is the recommended replacement for the LGB2K100B?
As the LGB series phases out, Siemens recommends the 3VA41 series, specifically catalog number 3VA41106ED240AA0, as the successor. Always confirm fit, form, and function for your specific application.
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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.