2CCS573103R8217 ABB S403M-K1NP 1A 3P+N Type K Miniature Circuit Breaker

Why Choose the ABB S403M-K1NP Miniature Circuit Breaker?

The ABB S403M-K1NP is a current-limiting 3P+N miniature circuit breaker (MCB) with protected neutral, designed to protect three-phase-plus-neutral electrical circuits against overload and short-circuit conditions. Part of the ABB SMISSLINE TP S400M-K series, it combines four-pole protection with the installation efficiency of ABB's modular plug-in distribution system.

Rated at 1 A with a Type K tripping characteristic, the S403M-K1NP is suited to appropriately engineered low-current circuits where connected equipment can produce elevated starting or inrush currents. The K characteristic makes it particularly useful for control, transformer, inductive and equipment circuits where unwanted operation during normal energisation needs to be avoided while maintaining effective circuit protection.

The S403M-K1NP provides a rated short-circuit capacity of 10 kA and a rated ultimate short-circuit breaking capacity (Icu) of 25 kA. Its neutral is protected at 100% of the nominal value of the pole conductor, while the four-module SMISSLINE TP plug-in construction enables efficient integration into compatible ABB distribution assemblies.

Key Advantages

• 3P+N configuration with protected neutral for comprehensive three-phase-plus-neutral circuit protection.
• 1 A rated current for appropriately designed low-current control, auxiliary and equipment circuits.
• Type K tripping characteristic suited to circuits with elevated starting or inrush currents.
• 10 kA rated short-circuit capacity for dependable fault protection.
• 25 kA ultimate short-circuit breaking capacity (Icu) for this current rating.
• Neutral protected at 100% of the nominal pole-conductor value.
• Energy-limiting class 3 helps reduce fault energy during short-circuit conditions.
• Plug-in construction for efficient integration with the ABB SMISSLINE TP system.

Key Features

• ABB SMISSLINE TP S400M-K series.
• 1 A rated current.
• 3P+N / four-pole configuration.
• Four protected poles.
• Type K tripping characteristic.
• 10 kA rated short-circuit capacity.
• 25 kA Icu.
• 240 / 415 V AC operational voltage.
• 440 V rated insulation voltage.
• 4 kV rated impulse withstand voltage.
• 50–60 Hz frequency.
• IP20 protection rating.

Reliable Protection for Low-Current Inductive Circuits

The ABB S403M-K1NP protects electrical conductors and connected circuits by automatically interrupting excessive current caused by overload or short-circuit conditions. Its current-limiting design helps reduce the electrical and thermal stresses associated with high fault currents while providing dependable protection across all four protected poles.

The Type K characteristic accommodates elevated transient currents that can occur when inductive equipment is energised. This makes the S403M-K1NP suitable for appropriately selected low-current transformer, control, automation and other inductive-load circuits, while its protected neutral and SMISSLINE TP plug-in architecture support efficient three-phase-plus-neutral distribution.

Typical Applications

• Three-phase-plus-neutral low-current circuits.
• Industrial control and auxiliary circuits.
• Control transformers and inductive equipment.
• Automation and machinery control systems.
• Electrical control panels and distribution assemblies.
• Low-current equipment with elevated energisation currents.
• ABB SMISSLINE TP distribution systems.