Siemens HHJXD63B400 - 400 A, 600 V, 3-Pole Bolt-On Circuit Breaker | AmpState

Siemens HHJXD63B400 is a 400 A, 600 V, 3-pole bolt-on molded case circuit breaker engineered to protect branch circuits in panelboards and loadcenters. Its bolt-on mounting delivers a rigid, vibration-resistant bus connection, helping maintain solid electrical contact even in demanding installations.

Why this breaker stands out

• Secure bolt-on mounting provides a dependable, vibration-resistant connection to the bus bars, reducing movement and arcing over time.
• Thermal-magnetic trip unit combines precise overload protection with fast short-circuit response, delivering stable, repeatable protection performance across varying temperatures.
• OEM-compatible design is built to pair with matching Siemens load centers and panelboards, making upgrades, replacements, and retrofits straightforward and reliable.
• Versatile installation suited for residential, commercial, and light industrial applications where robust, coordinated protection is essential.

Technical snapshot

• Manufacturer: Siemens
• Part Number: HHJXD63B400
• Type: Thermal-magnetic molded case circuit breaker
• Amperage Rating: 400 A
• Voltage Rating: 600 V
• Number of Poles: 3
• Mounting Style: Bolt-on
• Application: Branch circuit overcurrent and short-circuit protection

Optimal use cases

Ideal for protecting distribution circuits in panelboards and loadcenters that service three-phase systems. Use this breaker when you need to handle higher current for commercial spaces, light industrial equipment, or upgraded residential panels that feed multiple 3-phase loads. It’s well-suited for applications such as service panels in small offices, retail environments, or HVAC and motor feeders where reliable, coordinated protection is critical.

Installation and guidance

• Ensure proper alignment with the bus bars and secure the bolt-on mounting to achieve the intended, vibration-resistant connection.
• Follow all applicable electrical codes and Siemens installation guidelines. Use correct torque for mounting screws and verify fit with compatible OEM panelboards.
• Since this is a 3-pole device rated for 400 A at 600 V, confirm that your panelboard and downstream circuits are sized to safely accommodate this capacity.

With the Siemens HHJXD63B400, AmpState provides a robust, purpose-built solution for reliable branch circuit protection in demanding panelboard environments. When you need a trustworthy, OEM-compatible 3-pole bolt-on breaker that delivers consistent performance across a range of installations, this unit is engineered to meet the challenge.