Siemens LGB3B090B - 90 A, 600 V, 3-Pole Bolt-On Circuit Breaker | AmpState

Introducing the Siemens LGB3B090B, a robust 3-pole bolt-on molded case circuit breaker engineered to shield your electrical system from overcurrent and short circuits. With a 90 A rating and a 600 V maximum, this unit delivers dependable protection for panelboards and loadcenters across residential, commercial, and light industrial setups.

AmpState delivery and support: This Siemens breaker is stocked and supported by AmpState, helping you move from planning to protection with confidence.

Why this breaker stands out

• Secure bolt-on mounting: A rigid, vibration-resistant connection to the bus bar minimizes loose contacts, promoting consistent protection and reduced maintenance needs.
• Thermal-magnetic trip unit: Combines thermal overload sensing with magnetic instantaneous response, delivering stable, repeatable protection for both gradual overloads and sudden short circuits.
• OEM-compatible design: Engineered for seamless integration with matching Siemens OEM loadcenters and panelboards, ensuring proper fit, coordination, and reliable performance.
• Three-pole configuration: Ideal for balanced three-phase circuits in commercial spaces, light industrial panels, and modern residential installations requiring solid, comprehensive protection.

Technical profile

• Manufacturer: Siemens
• Part number: LGB3B090B
• Type: Thermal-magnetic molded case circuit breaker
• Amperage rating: 90 A
• Voltage rating: 600 V
• Number of poles: 3
• Mounting style: Bolt-on
• Applications: Branch circuit overcurrent and short-circuit protection

Who benefits from the LGB3B090B

Electrical professionals, facility managers, and property owners who need reliable protection in panelboards and load centers will appreciate the LGB3B090B. It’s especially well-suited for three-phase commercial equipment rooms, light industrial installations, and residential systems that demand robust, coordinated protection without compromising space or ease of maintenance.

How it solves common protection challenges

• Prevents insulation damage and equipment failure by delivering prompt, dependable protection against short circuits.
• Reduces nuisance trips during normal load fluctuations thanks to a thoughtfully designed thermal-magnetic trip curve.
• Minimizes connection issues with a secure bolt-on mount that stands up to vibration and continuous operation.

Practical guidance and use cases

Pair the LGB3B090B with compatible Siemens panelboards to ensure optimal fit and protective coordination. For maintenance, perform a visual inspection of the mounting screws and bus connections during regular service intervals, and keep the breaker in a clean, dry environment to preserve performance over time. Its 3-pole design makes it a compact, scalable solution for multi-phase systems where balanced protection is essential.