Siemens CJD63H400 - 400 A, 600 V, 3-Pole Bolt-On Circuit Breaker | AmpState

The Siemens CJD63H400 is a 400 A, 600 V, 3-pole bolt-on molded case circuit breaker designed to deliver dependable branch circuit overcurrent and short-circuit protection in panelboards and load centers. Built to handle demanding electrical environments, this unit pairs precise protection with a robust mounting system to keep connections secure even in vibration-prone installations.

Key features that matter in real-world panels

• Bolt-on mounting for a rigid, vibration-resistant bus connection that stays tight over time, reducing loose connections and ongoing maintenance.
• Thermal-magnetic trip unit delivers stable, repeatable protection by responding to both overloads and short circuits, helping to prevent nuisance tripping while safeguarding downstream equipment.
• OEM-compatible construction designed to pair with matching Siemens loadcenters and panelboards, supporting coordinated protection across the system.
• Versatile application suitable for residential, commercial, and light industrial electrical environments where reliable 3-phase protection is required.

Technical at-a-glance

• Manufacturer: Siemens
• Part number: CJD63H400
• Type: Thermal-magnetic molded case circuit breaker
• Amperage rating: 400 A
• Voltage rating: 600 V
• Poles: 3
• Mounting style: Bolt-on
• Application: Branch circuit overcurrent and short-circuit protection

Who should consider this breaker

Ideal for electricians and facilities managers designing or upgrading distribution panels in homes, small-to-medium commercial facilities, and light industrial settings. If your system uses 3-phase power and you need a robust, code-aligned protection device with a secure mounting method, the CJD63H400 offers a dependable solution.

Why it matters in your panel

Choosing a breaker that aligns with your panelboard or loadcenter ensures proper fit, predictable trip behavior, and streamlined maintenance. The CJD63H400’s combination of bolt-on stability and thermal-magnetic protection helps minimize downtime and protects wiring, motors, and downstream devices from damage due to overloads or faults.

Practical tips and best-use scenarios

• When planning 3-phase distribution, pair the CJD63H400 with compatible Siemens panelboards to ensure coordinated protection across all circuits.
• Use in applications where vibration resistance is important, such as equipment rooms, industrial settings, or panels subject to frequent door openings and movement.
• Inspect mounting hardware and bus connections during routine maintenance to preserve the integrity of the bolt-on connection.
• Follow local electrical codes and manufacturer torque specifications to ensure a reliable, long-lasting installation.