Siemens | LL3B400 | Circuit Breaker | 400A | 3-Pole | 600V

Siemens LL3B400 is a rugged, low-voltage circuit breaker engineered for reliable protection in demanding electrical distributions. This 400A, 3-Pole device delivers robust three-phase protection for up to 600V systems, making it a dependable choice for industrial and commercial panels that require solid, standardized protection.

• Amperage: 400A
• Poles: 3-Pole
• Voltage: 600V
• Part number: LL3B400

Why choose the Siemens LL3B400 for your panel or switchgear? This breaker is designed as a direct-fit option within Siemens-compatible systems, providing precise alignment with existing gear and reducing the risk of mismatched components during maintenance, retrofit, or replacement projects. The 3-pole configuration protects all phases of a three-phase circuit, helping ensure balanced protection across your distribution network while simplifying installation and future servicing.

Key use cases include:

• Maintenance replacements in existing Siemens panel boards where LL3B400 is specified
• Retrofits to upgrade older systems to a single, consistent 400A, 3-pole protection strategy
• New installations that require a Siemens-compatible 600V, 3-phase breaker with a 400A rating

Compared to generic or non-Siemens breakers, the LL3B400 aligns with Siemens design standards and compatibility expectations, helping ensure seamless operation within your protective scheme. This minimizes compatibility questions down the line and supports consistent protection across your electrical infrastructure.

Important note: Confirm fit and ratings before ordering. The part number LL3B400 is the best reference for compatibility with your equipment. If you’re upgrading or retrofitting, this specific model is designed to align with Siemens panels and switchgear that call for LL3B400, delivering reliable performance in demanding environments.