ABB | S5N-4P-400A | Circuit Breaker | 400A | 4-Pole | 600V

ABB S5N-4P-400A Circuit Breaker is a purpose-built protective device designed for demanding electrical installations where precise compatibility and reliable fault protection matter. With a 400A rating, 4-pole configuration, and a 600V operating envelope, this breaker is ready to safeguard large feeders and panelboards in industrial, commercial, and retrofit settings.

• Amperage: 400A
• Poles: 4-Pole
• Voltage: 600V
• Reference: S5N-4P-400A

What makes it unique is the deliberate alignment of its ratings with real-world panel and feeder needs. This isn’t a generic replacement — it’s a precise match for maintenance, retrofit, or replacement projects where the exact part number and performance characteristics drive safe, code-compliant protection in three-phase systems (with the potential neutral connection on the 4-pole configuration). The S5N-4P-400A ensures coordinated protection across the circuit, helping to prevent equipment damage and electrical downtime.

Ideal use scenarios include:

• Upgrading an aging service panel to handle heavier loads in a 3-phase system.
• Replacing a failed breaker in a 600V installation while preserving existing wiring and enclosure fit.
• Retrofit projects where exact amperage, pole count, and voltage ratings are required to maintain system reliability.

Compatibility and procurement guidance — before you order, verify the fit and ratings for your specific installation. The part number S5N-4P-400A is the most reliable reference for compatibility, ensuring correct physical fit and electrical performance in your panelboard or switchgear. If your setup calls for a 400A, 4-pole device in a 600V system, this ABB breaker is designed to meet that precise specification.

Practical tips for optimal protection — consider pairing this breaker with appropriate enclosure clearance and panel labeling to reflect its 4-pole, 600V protection role. Document the exact part number in your maintenance records to simplify future replacements or retrofits and minimize downtime during service events.