ST-3N 3P250A Molded Case Circuit Breaker

ST-3N 3P250A Molded Case Circuit Breaker with 690V AC rating, advanced arc-extinguishing technology, and reliable overload, short-circuit, and undervoltage protection for industrial power distribution.

  • Rated Voltage (Ue): 240V, 400V, 415V, 500V, 690V AC (50/60Hz)
  • Rated Current (In): 10A to 630A (selectable in segments)
  • Insulation Voltage (Ui): 800V or 1000V (standard/high - insulation type)
  • Impulse Withstand Voltage (Uimp): 8kV
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Description

Product Overview

The Stmax – T series molded case circuit breakers are high – performance electrical protection devices specifically designed for industrial and commercial power distribution systems. They are suitable for AC circuits with a frequency of 50/60Hz, with a maximum rated voltage of 690V AC and a rated current range from 10A to 630A. This series of circuit breakers integrates advanced arc – extinguishing technology and current – limiting functions, and is widely used in power distribution, motor protection, capacitor protection, and end – user equipment, providing reliable protection against overload, short – circuit, and undervoltage.

Core Performance Features

  • Excellent Current – Limiting Ability
  • The innovative arc – extinguishing system can cut off high short – circuit currents in an extremely short time (<1ms), significantly reducing the peak value of fault currents and minimizing the risk of equipment damage.

Modular Design and Flexible Configuration

  • Supports 3P (three – pole) and 4P (four – pole) configurations to meet different power distribution requirements.
  • Offers two types of trip units: thermal – magnetic (with fixed tripping characteristics) and electronic (with adjustable tripping curves), satisfying diverse application scenarios.
  • Optional residual current operated circuit – breaker with overcurrent protection (RCBO) modules can be added to enhance the safety protection of people and equipment.

Compact Structure and High Reliability

  • The compact design saves space in the power distribution cabinet and facilitates dense installation.
  • The all – metal operating mechanism (independent of the housing for positioning) ensures long – term mechanical stability and anti – interference ability during operation.
  • The housing is made of thermosetting materials, which have excellent high – temperature resistance and fire – proof performance, and will not melt or deform even at high temperatures.

Global Certification and Environmental Compliance

  • Complies with international standards such as IEC 60947 – 2 and UL 489, and has obtained certifications from multiple countries such as CE, CCC, UL, and CSA.
  • Uses halogen – free materials and environmentally friendly manufacturing processes, complying with RoHS and REACH regulations.

Typical Application Scenarios

  • Industrial Field: Motor control centers (MCC), capacitor bank protection, production line power distribution.
  • Commercial Buildings: Data center power distribution, elevator control systems, HVAC system protection.
  • Infrastructure: Railway power supply systems, photovoltaic inverter protection, urban power grid renovation.
  • Special Environments: Explosion – proof areas in chemical plants, offshore platforms, high – temperature and high – humidity industrial workshops.

Technical Parameters

Parameter Specification
Rated Voltage (Ue) 240V, 400V, 415V, 500V, 690V AC (50/60Hz)
Rated Current (In) 10A to 630A (selectable in segments)
Insulation Voltage (Ui) 800V or 1000V (standard/high – insulation type)
Impulse Withstand Voltage (Uimp) 8kV
Trip Type – Thermal – magnetic (B/C/D curves)
– Electronic (adjustable long – time delay, instantaneous, short – time delay)

ST 3N 3P250A Molded Case Circuit Breaker (5) ST 3N 3P250A Molded Case Circuit Breaker (6)

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