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Phone：+86 17062388866Description
The TELKOOR AC-3U-250 is a heavy-duty 3-pole electromechanical contactor designed for industrial motor control and power switching applications. Rated for 250A at 400V AC, this robust device enables reliable switching of high-current loads such as motors, transformers, and resistive heating systems. Engineered with industrial-grade silver alloy contacts and arc suppression chambers, the AC-3U-250 ensures >100,000 electrical operations at full load (AC-3 category) while minimizing contact erosion. Its modular design allows direct mounting of thermal overload relays for comprehensive motor protection.
Encased in heat-resistant thermoplastic (UL94 V-0), the contactor features corrosion-resistant plating on terminals and a compact footprint optimized for panel space efficiency. The TELKOOR AC-3U-250 operates across a wide control voltage range (24–500V AC/DC) and incorporates built-in surge suppression for coil longevity. Ideal for harsh environments, its sealed construction resists dust, oil mist, and humidity per IEC/EN 60947-4-1 standards, making it indispensable for manufacturing automation, HVAC systems, and heavy machinery where switching reliability directly impacts operational uptime.
TELKOOR AC-3U-250
Technical Specifications
| Parameter Name | Parameter Value |
| Product Model | TELKOOR AC-3U-250 |
| Manufacturer | TELKOOR (Industrial Controls) |
| Product Type | 3-Pole Electromechanical Contactor |
| Rated Operational Current (Ie) | 250 A (AC-3, 400V) |
| Rated Insulation Voltage (Ui) | 690 V AC |
| Rated Thermal Current (Ith) | 310 A |
| Poles | 3 (Main Contacts) + 1 NO + 1 NC (Auxiliary) |
| Rated Control Voltage | 24–500 V AC/DC (selectable) |
| Mechanical Life | ≥10 million operations |
| Electrical Life (AC-3) | ≥100,000 operations |
| Contact Material | Silver Tin Oxide (AgSnO₂) |
| Terminal Type | Screw Clamp (35 mm² max) |
| Mounting | DIN Rail (35 mm) or Panel Screw |
| Operating Temperature | -25°C to +60°C |
| Protection Class | IP20 (Terminals), IP00 (Internal) |
| Standards | IEC/EN 60947-4-1, UL 508 |
Main Features and Advantages
High-Performance Switching: Optimized magnetic blowout design rapidly extinguishes arcs during contact separation, reducing wear even at 250A inductive loads. Dual-break contacts distribute thermal stress, while AgSnO₂ contact material resists welding during inrush currents up to 2,500A.
Adaptive Control: Universal coil technology accepts 24–500V AC/DC without additional converters. Built-in varistor suppresses voltage spikes >1.8 kV, protecting PLC outputs. Snap-action mechanism ensures positive contact pressure under vibration (IEC 60068-2-6).
Maintenance Efficiency: Transparent cover allows visual inspection of contacts without disassembly. Quick-release auxiliary contact blocks enable field reconfiguration (NO/NC interchange). Integrated mechanical indicator shows contact position for troubleshooting.
Application Field
The TELKOOR AC-3U-250 excels in:
Industrial Motors: Switching crushers, conveyor belts, and pumps in mining/mineral processing (AC-3 duty).
Energy Infrastructure: Controlling transformer tap changers and capacitor banks in substations.
HVAC Systems: Power switching for chillers and compressors >150 kW.
Manufacturing: Automated production line motor starters in automotive/steel plants.
Renewables: Disconnecting inverters in solar farms during maintenance.
TELKOOR AC-3U-250
Related Products
TELKOOR LR9-250: Thermal overload relay for AC-3U-250 (200–250A setting range).
TELKOOR CA7-40: Surge suppressor module for DC coils.
TELKOOR ZB6-4: 4-pole auxiliary contact block for status feedback.
TELKOOR GV3-250: Circuit breaker for upstream protection.
TELKOOR AC-3U-180: Lower-current variant (180A) for space-constrained panels.
