Siemens LGG3B125 - 125 A, 600 V, 3-Pole Circuit Breaker | AmpState

Siemens LGG3B125 is a rugged 125A, 600V, 3-pole molded-case circuit breaker designed for dependable branch circuit protection in panelboards and load centers. Its compact form and precise trip technology make it a smart choice for modern electrical installations where space, safety, and reliability matter.

• Space-efficient molded-case design minimizes panel footprint and frees up space for future circuits, helping you optimize enclosure layouts without compromising protection.
• Thermal-magnetic trip unit delivers stable, repeatable protection: the thermal element handles normal overloads with predictable response, while the magnetic element provides instantaneous trip for short circuits.
• 3-pole configuration for 3-phase systems ideal for 3-phase commercial and light industrial feeders, ensuring coordinated protection across all lines.
• OEM-grade compatibility matched to Siemens OEM loadcenters and panelboards for straightforward installation, proper fit, and reliable electrical coordination.
• Wide application range suitable for residential upgrades, small commercial panels, and light-industrial feeders that require dependable overcurrent and short-circuit protection.

Technical snapshot:

• Manufacturer: Siemens
• Part Number: LGG3B125
• Type: Thermal-magnetic molded case circuit breaker
• Amperage Rating: 125 A
• Voltage Rating: 600 V
• Number of Poles: 3
• Application: Branch circuit overcurrent and short-circuit protection

Real-world use cases and benefits:

• Upgrade an aging residential panel to safely power added lighting, outlets, and small appliances with predictable trip behavior.
• Feed a 3-phase circuit in a commercial panel, such as a small office or storefront, while maintaining proper protection coordination across all phases.
• Replace a failing breaker in a compact load center where space is at a premium, preserving panel organization and safety margins.

Why this Siemens LGG3B125 stands out: it’s built for reliable protection where it matters most—wiring, devices, and people. The combination of a robust 125 A rating, 600 V insulation, and a thermal-magnetic trip mechanism provides consistent performance across varying loads and short-circuit events, reducing nuisance trips and promoting safer electrical operation. When paired with appropriate Siemens loadcenters and panelboards, it delivers seamless installation, clear electrical coordination, and long-term peace of mind for both professionals and seasoned DIYers.

Ready to invest in steadfast protection for your panels? Choose the Siemens LGG3B125 125A 600V 3-Pole molded-case circuit breaker for dependable, code-compliant branch circuit protection in your next electrical project.