Siemens SCJD6B400LSI - 400 A, 3-Pole Circuit Breaker | AmpState

Meet the Siemens SCJD6B400LSI—a robust 400A, 3-pole molded case circuit breaker designed to deliver dependable branch circuit protection in panelboards and loadcenters. Built for demanding environments, this device combines compact physical size with serious protection capabilities, making it a smart choice for higher-current, three-phase installations.

Why this breaker stands out

• 400A, 3-pole protection for reliable control of three-phase circuits, consolidating protection for large loads into a single, space-efficient unit.
• Thermal-magnetic trip unit delivers stable, repeatable protection by combining fast magnetic response to short circuits with dependable thermal overload sensing.
• Compact molded case design maximizes panel space and simplifies wiring layouts without compromising protection performance.
• OEM-compatible engineered to pair with matching Siemens loadcenters and panelboards, ensuring coordinated trip characteristics and clean labeling.
• Versatile across sectors suitable for residential, commercial, and light industrial applications, providing a single, reliable solution for diverse projects.

What you gain in daily operation

With a 400A rating and three-pole construction, this breaker is ideal for feeding large circuits or serving as a protective device within appropriately sized panels. The thermal-magnetic trip system responds decisively to short circuits while reducing nuisance trips during temporary overloads. The compact form factor supports cleaner panel layouts and easier wiring management in crowded electrical enclosures.

Technical snapshot

• Manufacturer: Siemens
• Part Number: SCJD6B400LSI
• Type: Thermal-magnetic molded case circuit breaker
• Amperage Rating: 400A
• Number of Poles: 3
• Application: Branch circuit overcurrent and short-circuit protection

Ideal for

Electricians and panel installers addressing large residential subpanels, commercial electrical rooms, and light-industrial installations where high-current, reliable protection is essential. If you need a Siemens-aligned, three-phase protection device that integrates seamlessly with your existing panel setup, this SCJD6B400LSI delivers consistent performance and straightforward installation.

Installation and compatibility tips

• Choose Siemens OEM loadcenters and panelboards when maximum system coordination and labeling clarity are priorities.
• Follow standard electrical practices for three-phase panels, and torque specifications provided by panelboard manufacturers to ensure secure, code-compliant connections.