Siemens B345 45A 3P 240V Circuit Breaker, Bolt-On | AmpState

The Siemens B345 45A 3P 240V Bolt-On Circuit Breaker from AmpState is built to handle everyday electrical protection with precision and reliability. Designed for panelboards, load centers, and distributed electrical systems, this 3-pole breaker ensures consistent performance across three-phase circuits while keeping your BOM aligned to the original part number. It’s an excellent choice for replacement projects and stocking spares, helping you minimize downtime and keep critical equipment protected.

Key advantages that set the B345 apart

• Bolt-on mounting provides a secure, robust connection in compatible panels, reducing loosening under vibration and load transients.
• Three-pole configuration delivers reliable protection for 3-phase circuits, streamlining installation in commercial and industrial environments.
• 45 A rating offers balanced protection for medium-load electrical distributions without unnecessary nuisance tripping.
• 240 V operation aligns with standard three-phase service requirements found in many panelboards and distribution setups.
• Original part alignment ensures BOM fidelity, making it easier to source exact replacements that match existing installations.
• AmpState availability means you can timely acquire this Siemens breaker with confidence and support for compatibility questions.

Ideal use cases

• Replacing a worn or damaged breaker in panelboards and load centers where the B345 is specified.
• Stocking a spare that directly matches the original part number to reduce downtime during maintenance windows.
• Ensuring consistent protection in 3-phase electrical distribution where 45 A, 3-pole 240 V devices are required.
• Projects aiming to maintain BOM consistency and traceability with Siemens components.

What you’ll get and how to verify compatibility

• Part number: B345
• Manufacturer: Siemens
• Amperage: 45 A
• Poles: 3
• Voltage: 240 V
• Application: Circuit protection in panelboards, load centers, and electrical distribution

Need help matching a part number or confirming compatibility with your setup? Message us and we’ll help you confirm the fit for your panel and BOM. Upgrade your electrical protection with a trusted Siemens solution and keep your distribution system safely protected and functioning smoothly.