ABB 1SDA066571R1 A3S 400 TMF 400-4000 4p F F InN=100%In 4P 400A Fixed Power Circuit-Breaker

The ABB 1SDA066571R1 — catalog number A3S 400 TMF 400-4000 4p F F InN=100%In — is a 4-pole, 400 A fixed-mount power circuit-breaker from the Formula A3S series, engineered for transformer, generator, and installation protection in demanding industrial environments. With a TMF thermal-magnetic trip unit, 100% neutral current rating (InN=100%In), and a compact fixed design, this breaker delivers robust overcurrent and short-circuit protection for 4-wire distribution systems.

Technical Specifications

Certifications & Standards

• CE: Conforms to European Union directives for electrical equipment safety and electromagnetic compatibility
• IEC: Designed and tested in accordance with IEC standards for power circuit-breakers
• RoHS: Compliant with EU Restriction of Hazardous Substances Directive — restricts use of specific harmful materials
• REACH: Compliant with EU REACH regulation governing chemicals and safe use in industrial products
• WEEE: Registered under the Waste Electrical and Electronic Equipment Directive for responsible end-of-life disposal

Applications & Use Cases

• Transformer feeder and outgoing protection in main distribution boards
• Generator protection in standby and prime power installations
• Industrial installation protection in manufacturing plants and process facilities
• 4-wire (3-phase + neutral) distribution systems requiring full neutral current protection (InN=100%In)
• Control panels and motor control centers requiring compact, fixed-mount circuit protection