Siemens LGB2B125B Circuit Breaker – VL Series – 125A – 2 Pole – 600VAC – Thermal Magnetic – Bolt-On – Panelboard Mount

The Siemens LGB2B125B is a VL Series molded case circuit breaker designed to provide reliable overload and short-circuit protection for commercial, institutional, and industrial electrical distribution systems. Rated at 125A and 600VAC, this 2-pole breaker is engineered for single-phase applications requiring compact construction, high interrupting capacity, and dependable electrical performance.

Equipped with a thermal-magnetic trip unit featuring Long-Time and Instantaneous (LI) protection functions, the LGB2B125B delivers effective protection against sustained overloads and high-level fault currents. Its high interrupting capacity of 100kA at 240VAC ensures strong fault-clearing performance in demanding electrical environments.

Built on Siemens’ VL Series (LGB frame), this breaker is designed for panelboard mounting and supports reverse-feed applications, providing installation flexibility. It includes load-side lug terminals and is engineered for secure connections and long-term operational reliability.

Specifications

• Brand: Siemens Breakers
• Part Number: LGB2B125B
• Series: VL Series
• Type: LGB Molded Case Circuit Breaker
• Frame Type: G Frame (LGB)
• Category: Molded Case Circuit Breaker
• Mounting Type: Bolt-On
• Installation Type: Panelboard Mounting
• Protection Type: Thermal Magnetic
• Trip Functions: LI – Long-Time and Instantaneous
• Special Features: Reverse Feed Suitable

Electrical Ratings

• Current Rating: 125A
• Voltage Rating: 600VAC
• Number of Poles: 2 Pole
• Phase: 1 Phase
• Interrupting Capacity: 100kA @ 240VAC
• Terminal Configuration: Load Side Lug Terminals Included

Construction

• Compact molded case design
• VL Series G-frame construction
• Thermal-magnetic trip mechanism
• Bolt-on mounting configuration
• Panelboard installation compatible
• High interrupting capacity structure
• Load-side lug terminals included
• Durable industrial-grade housing

Functions

• Overload protection
• Short-circuit protection
• Long-time delay protection
• Instantaneous fault protection
• Circuit switching and isolation

Dimensions

• Height: 4.99 in
• Width: 1.97 in
• Depth: 2.87 in
• Weight: 1.85 lbs

Standards

• UL Listed
• CSA Approved

Applications

• Commercial electrical distribution systems
• Industrial panelboards
• Branch circuit protection
• High fault-current installations
• Institutional electrical systems
• Lighting and power distribution circuits

Returns are easy

You may return items within 30 days of delivery for a refund.

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