ZHUCO SZW26-160/D303.3 1-0-2 Three-position three-section high-current changeover switch

The SZW26-160/D303.3 is a three-position (1-0-2), three-section (three-layer) rotary changeover switch with a rated current of up to 160A, designed for reliable manual switching between two independent sets of three-phase high-current loads or power sources. It features a three-layer contact structure, allowing for simultaneous switching of three-phase circuits via a single handle, ensuring operational uniformity and safety.
Key Parameters and Features
Electrical Specifications:
Rated Operating Voltage: AC 440V (50/60Hz)
Rated Insulation Voltage: 660V
Rated Current: 160A
Contact Configuration and Logic: Three-layer structure, each layer independently controlling one phase.
Position I: Connects the first set of three-phase output circuits (contacts 1-2, 5-6, 9-10).
Position 0: All contacts are completely disconnected, providing a clear and safe electrical isolation point.
Position II: Connects the second set of three-phase output circuits (contacts 3-4, 7-8, 11-12).
Structure and Materials:
Contacts: Special high-capacity silver alloy, ensuring low contact resistance, high conductivity, and arc resistance at 160A current.
Conductors: Heavy-duty thickened copper components, meeting the requirements for long-term current carrying and heat dissipation at ultra-high currents.
Insulation and Housing: Made of high-strength, flame-retardant, high-temperature resistant, environmentally friendly engineering plastic, ensuring reliable mechanical and electrical performance.
Environmental Conditions:
Operating Temperature: -25°C to +40°C (average temperature over 24 hours ≤ +35°C)
Altitude: ≤ 2000 meters
Relative Humidity: ≤ 50% at +40°C; up to 90% at +20°C (protection against condensation is required). Lifespan Specifications:
Mechanical life: ≥ 300,000 cycles
Electrical life: ≥ 60,000 cycles (at rated 160A load, operating frequency ≤ 120 times/hour)
Application Scenarios:
This switch is specifically designed for critical industrial applications requiring manual switching of very high current three-phase circuits. It is a core manual component for achieving highly reliable power selection and load control.
Key Applications: As a manual transfer switch for 160A class ultra-high power dual power sources (such as two mains power lines, or mains power and a generator), providing power supply assurance for heavy loads.
Load Control: Used to control the "one-use, one-standby" operating mode switching of two three-phase high-power devices with a rated current of up to 160A (such as large water pumps, compressors, and arc furnace transformers).
Safety Maintenance Isolation: Provides a reliable manual electrical isolation point ("0" position) during maintenance of heavy industrial equipment, and is a key hardware component for implementing safety lockout/tagout (LOTO) procedures.