Siemens FXD63B100L - 100 A, 600 V, 3-Pole Bolt-On Circuit Breaker | AmpState

Meet the Siemens FXD63B100L—a 3-pole, 100A, 600V bolt-on molded case circuit breaker designed to deliver dependable branch circuit overcurrent and short-circuit protection in panelboards and loadcenters. This unit is built for installations where reliability and solid electrical connections matter most, from residential to commercial and light industrial settings.

Why this FXD63B100L stands out

• Secure bolt-on mounting for a rigid, vibration-resistant bus connection that stays locked in even in demanding environments.
• Thermal-magnetic trip unit combines a thermal overload element with an instantaneous magnetic trip, delivering stable, repeatable protection across temperature changes and fault conditions.
• OEM-compatible design is tailored to pair with matching Siemens OEM loadcenters and panelboards, ensuring straightforward installation and reliable operation.
• Versatile application suitable for residential, commercial, and light industrial electrical distributions that require robust three-phase protection.

Technical snapshot

• Manufacturer: Siemens
• Part Number: FXD63B100L
• Type: Thermal-magnetic molded case circuit breaker
• Amperage Rating: 100 A
• Voltage Rating: 600 V
• Number of Poles: 3
• Mounting Style: Bolt-on
• Application: Branch circuit overcurrent and short-circuit protection

Who should consider this breaker?

Ideal for panels and load centers that require reliable three-phase protection with a sturdy mechanical mount. Use it to safeguard feeders, motor circuits, lighting distributions, and other branch circuits in spaces where vibration resistance and consistent trip performance matter—ranging from home electrical panels to small-scale commercial or industrial installations.

How it compares and how to use it

Compared to non-bolt-on options, the FXD63B100L’s bolt-on mounting provides a more rigid bus connection, reducing contact looseness and arcing over time. Its thermal-magnetic trip unit delivers predictable responses: slow, controlled protection against minor overloads and immediate action for high-fault conditions. Because it’s designed to match Siemens OEM loadcenters and panelboards, you’ll experience smoother field upgrades, compatible mounting footprints, and fewer compatibility headaches during installation.

Practical installation and use tips

• Confirm panelboard compatibility with Siemens OEM loadcenters when selecting this 3-pole, 100 A device to ensure proper fit and electrical performance.
• Use the bolt-on mounting as directed by Siemens installation guidelines to achieve the vibration resistance and secure bus connection described here.
• In environments with wide temperature swings, rely on the thermal-magnetic trip to maintain stable protection without nuisance trips.
• For best results, pair this breaker with circuits within its 100 A rating and ensure conductors and wiring comply with local codes and panel specifications.

The Siemens FXD63B100L is a purpose-built solution for durable, reliable three-phase protection in panelboards and loadcenters. It combines a rugged bolt-on mount, a responsive thermal-magnetic trip mechanism, and OEM compatibility to keep your electrical distribution safe and performing as designed.