Siemens HJXD63B300 - 300 A, 600 V, 3-Pole Bolt-On Circuit Breaker | AmpState

Siemens HJXD63B300 — the 300 A, 600 V, 3-pole bolt-on molded case circuit breaker designed to protect your panelboards and load centers with precision and confidence. This unit is purpose-built for dependable branch circuit overcurrent and short-circuit protection in homes, offices, and light industrial environments.

Key advantages that set it apart:

• Secure bolt-on mounting delivers a rigid, vibration-resistant bus connection, reducing the risk of loose contacts and arc wear in crowded electrical enclosures.
• Thermal-magnetic trip unit provides stable, repeatable protection by combining long-term overload detection with instantaneous short‑circuit interruption, helping to minimize nuisance trips while quickly isolating faults.
• Three-pole configuration supports three-phase power distribution, making it ideal for commercial spaces and light industrial equipment where balanced protection matters most.
• OEM-friendly compatibility is designed to work with matching Siemens load centers and panelboards, ensuring seamless integration and coordinated protection across the system.
• Versatile application suitable for residential, commercial, and light industrial applications that demand reliable fault isolation and durable performance.

What it protects and how it helps you

• Prevents damage from overcurrent events and short circuits by interrupting fault currents at the source, safeguarding downstream equipment and reducing downtime.
• Helps maintain electrical safety and service continuity in panelboards and load centers where steady operation and predictable trips are essential.
• Facilitates future upgrades or retrofits by offering a compatible bolt-on solution that plugs into existing Siemens ecosystems without custom adapters.

Technical specifications at a glance

• Manufacturer: Siemens
• Part number: HJXD63B300
• Type: Thermal-magnetic molded case circuit breaker
• Amperage rating: 300 A
• Voltage rating: 600 V
• Poles: 3
• Mounting style: Bolt-on
• Application: Branch circuit overcurrent and short-circuit protection

Ideal for electricians and facilities professionals seeking a robust, field-proven protection solution, the Siemens HJXD63B300 delivers clear fault isolation, durable construction, and seamless compatibility with Siemens panelboards. Add this bolt-on, 3‑pole circuit breaker to your next panel upgrade or service improvement to ensure reliable, long-lasting protection for three-phase circuits.