Siemens MBK125 - 125 A, 240 V, 2-Pole Plug-In Circuit Breaker | AmpState

Designed by Siemens for dependable branch circuit protection, the MBK125 is a 125A, 240V, 2-pole plug-in molded-case circuit breaker built to safeguard panelboards and load centers in demanding residential, commercial, and light industrial environments. With a fast plug-in connection and precise thermal-magnetic trip, it delivers confident protection where it matters most.

• Fast plug-in connection for quick installation and simple replacements, reducing downtime during panel upgrades or service calls.
• Thermal-magnetic trip unit provides stable, repeatable protection against overloads and short circuits, ensuring predictable breaker behavior across temperature variations.
• 2-pole design protects both hot conductors on 240V circuits, delivering coordinated safety for multi-wire branch circuits and minimizing nuisance trips on shared neutrals.
• OEM-compatible engineered to fit seamlessly with matching Siemens OEM load centers and panelboards for reliable electrical coordination and ease of procurement.
• Versatile application ideal for residential service panels, commercial distribution boards, and light industrial equipment racks that require robust, plug-in protection.

Technical Snapshot

• Manufacturer: Siemens
• Part Number: MBK125
• Type: Thermal-magnetic molded-case circuit breaker
• Amperage Rating: 125A
• Voltage Rating: 240V
• Number of Poles: 2
• Mounting Style: Plug-in
• Application: Branch circuit overcurrent and short-circuit protection

Ideal Use Cases

Install the MBK125 in panelboards and load centers where reliable 240V protection is required. It’s well-suited for feeders and branch circuits in homes with high electrical demand, light commercial storefronts, and small industrial setups where quick replacements and consistent trip characteristics minimize downtime and protect valuable equipment.

Why choose this Siemens MBK125

Unlike generic breakers, the MBK125 is built to match Siemens’ established performance standards, offering predictable trip response and seamless integration with Siemens panel ecosystems. Its plug-in format helps technicians perform fast replacements without sacrificing safety, while the 125A rating provides scalability for expanding circuits or higher-load applications.

whether you’re upgrading an aging panel, wiring a new subpanel, or stocking a technician’s replacement kit, the MBK125 2-pole plug-in molded-case breaker delivers trusted protection with practical, real-world advantages that keep electrical systems running smoothly.