Siemens | Q145 | Circuit Breaker | 45A | 1-Pole | 120V | Plug-In

Meet the Siemens Q145 Circuit Breaker—a precise, plug-in protection solution designed for reliable overcurrent protection in residential and light commercial panels. This 45A, 1-pole unit operates at 120V and is engineered for quick, straightforward plug-in installation, making maintenance, retrofit, and replacement tasks faster and more predictable.

What makes the Siemens Q145 special

Unlike generic substitutes, the Q145 is built to align with Siemens’ Q-series specifications, ensuring a clean fit and dependable performance when you’re restoring or upgrading your panel. Its 1-pole design concentrates protection exactly where you need it, helping you manage branch circuits with confidence while preserving overall panel reliability.

Key specifications

• Amperage: 45A
• Poles: 1-Pole
• Voltage: 120V
• Type: Plug-In
• Part Number: Q145

Ideal use cases

• Maintenance: Replace a worn or tripped breaker to restore stable circuit protection without reworking the panel.
• Retrofit: Upgrade or refresh circuits in compatible Siemens panels that require a Q145 specifically.
• Replacement: When specs match, use the exact part number (Q145) to ensure compatibility and reliable performance.

Why this matters for your project

Choosing the exact part number—Q145—minimizes compatibility risks and avoids guesswork that can come with generic breakers. The plug-in design reduces installation time and disturbance to surrounding components, helping electricians and DIYers alike complete a clean, safe replacement with less downtime.

Fit, check, and install with confidence

Before ordering, confirm your panel's compatibility by matching to the Q145 part number and ensuring the ratings align with your circuit requirements. The best reference for compatibility is the exact part number—Q145—to ensure the breaker fits the bus and meets the protection needs of your 120V, 45A circuit.