Siemens CJD63S400 A - 400 A, 600 V, 3-Pole Bolt-On Circuit Breaker | AmpState

Siemens CJD63S400A is a 400A, 600V, 3-pole bolt-on molded case circuit breaker engineered to protect electrical systems from overcurrent and short circuits. Built for dependable performance in panelboards and load centers, this unit combines rugged construction with precise protection to keep critical circuits safe and operational.

• Amperage rating: 400 A
• Voltage rating: 600 V
• Poles: 3
• Mounting style: Bolt-on
• Type: Thermal-magnetic molded case circuit breaker
• Application: Branch circuit protection in panelboards/loadcenters

Why this matters

The thermal-magnetic trip unit delivers stable, repeatable protection by combining time-delay thermal sensing for overloads with fast magnetic tripping for intense short-circuit events. This means fewer nuisance trips during normal startup surges and faster responses when a fault occurs, helping to safeguard wiring, equipment, and downstream devices in demanding electrical environments.

Ideal for

• Residential, commercial, and light industrial applications requiring reliable 3‑pole protection in three-phase circuits
• Panelboards and OEM load centers that demand seamless Siemens compatibility and bolt-on mounting
• Upgrades or replacements in existing distribution systems that rely on solid, secure bus connections

Practical benefits and use cases

• Secure, vibration-resistant bus connection through bolt-on mounting, reducing movement and loosening in busy electrical environments
• Robust protection for circuits feeding motors, HVAC equipment, pumps, lighting, and other load centers
• Clear path for field replacement in compatible Siemens panelboards, helping minimize downtime during service or upgrades
• Compatible with matching OEM load centers and panelboards to maintain system integrity and warranty considerations

With the Siemens CJD63S400A, you get a purpose-built solution for reliable branch circuit protection in demanding settings. Its 3-pole design and 400A capacity are tailored for three-phase systems and larger distribution schemes, delivering dependable protection without compromising on installation practicality.

Upgrade or install with confidence in panelboards and load centers that require a bolt-on, thermal-magnetic molded case circuit breaker designed for consistent performance across residential, commercial, and light industrial applications.