Siemens | BQ2B040QX | Circuit Breaker | 40A | 2-Pole | 240V | 10kA | Bolt-On

Siemens BQ2B040QX is a bolt-on, 2-pole circuit breaker rated at 40A and 240V, engineered to deliver reliable overcurrent protection for 240V branch circuits. Designed for maintenance, retrofit, and replacement tasks where exact Siemens specifications are required, this unit helps you restore safe and compliant electrical service with confidence.

• Amperage: 40A
• Poles: 2-Pole
• Voltage: 240V
• Interrupting Rating: 10kA
• Mounting: Bolt-On
• Part Reference: BQ2B040QX

Built for secure, reliable integration in Siemens panels

This breaker is part of Siemens’ bolt-on family, engineered to mount firmly in compatible load centers. The bolt-on design provides a solid mechanical connection, minimizing loose contacts and ensuring consistent trip performance in demanding environments.

Why the 10kA rating and 240V, 40A specs matter

The 10kA interrupting capacity equips this breaker to safely interrupt high fault currents, protecting wiring and downstream devices. At 240V, it is well-suited for common heavy-load circuits such as air conditioning systems, electric water heaters, and other large appliances typically found in residential or light commercial settings.

Ideal use cases and who should consider it

Use the BQ2B040QX for replacement in panels that require a 40A, 2-pole, 240V bolt-on Siemens breaker. It’s a smart choice for upgrading older installations, performing panel retrofits, or maintaining service reliability in facilities that rely on Siemens protection schemes. Always verify panel compatibility and ratings with the panel labeling and reference the BQ2B040QX part number to ensure proper fit.

Installation and safety essentials

Before installation, Power down the main disconnect and follow standard safety practices for electrical work. Ensure the circuit is de-energized, properly torque mounting screws for a secure bolt-on connection, and route conductors according to panel guidelines. If you’re uncertain about compatibility or wiring standards, consult a licensed electrician to avoid misalignment or unsafe connections.