Siemens B170 - 70 A, 120 V, 1-Pole Bolt-On Circuit Breaker | AmpState

Meet the Siemens B170, a 70-amp, 120-volt, 1-pole bolt-on molded case circuit breaker designed to deliver dependable overcurrent and short-circuit protection in panelboards and load centers. Built for reliability, this breaker features a secure bolt-on mounting that forms a rigid, vibration-resistant bus connection, and a thermal-magnetic trip unit that provides stable, repeatable protection performance across a range of electrical conditions. Ideal for residential, commercial, and light industrial applications, the B170 plugs into matching OEM load centers for seamless integration.

Key advantages

• Secure bolt-on mounting: ensures a rigid, vibration-resistant connection to the bus, reducing movement and potential arcing.
• Thermal-magnetic protection: combines precise overload and short-circuit triggering for dependable, predictable response.
• 1-pole, 70A, 120V: tailored to protect higher-current branch circuits on standard 120-volt systems.
• Molded case construction: rugged housing designed to withstand everyday electrical environments and handling.
• OEM load center compatibility: engineered to work with Siemens matching panelboards and load centers for straightforward replacements.
• Versatile across settings: suitable for residential, commercial, and light industrial panel configurations.

What it protects and why it matters

The B170 guards branch circuits from dangerous overcurrents and short circuits. Its thermal-magnetic trip unit delivers fast, reliable protection when current spikes occur, helping prevent wiring damage, nuisance trips, and potential electrical fires. By selecting a 70A rating, you tailor protection to circuits with higher current demands, such as larger appliances, subpanels, or HVAC feeders, while maintaining safe and efficient operation.

Technical snapshot

• Manufacturer: Siemens
• Part Number: B170
• Type: Thermal-magnetic molded case circuit breaker
• Amperage Rating: 70A
• Voltage Rating: 120V
• Number of Poles: 1
• Mounting Style: Bolt-on
• Application: Branch circuit overcurrent and short-circuit protection

Installation and usage tips

For optimal performance, ensure your panelboard or load center is compatible with bolt-on B-series breakers and that conductor sizing and enclosure ratings align with 70A protection. Always shut off main power and follow local electrical codes during installation. Adhere to manufacturer guidelines for torque and termination to maintain a secure, long-lasting connection. When in doubt, consult a qualified electrician to confirm proper fit and wiring integrity.

Why choose Siemens B170

Beyond basic protection, the B170 emphasizes reliability in environments where vibration or movement could affect connections. The bolt-on design minimizes connectivity failures, while the thermal-magnetic trip system delivers consistent, time-proven performance. This combination translates to fewer nuisance trips and improved uptime for critical circuits in homes, offices, and light industrial spaces.