Siemens Industrial Controls 3RT2028-1AN20 Contactor

The Siemens 3RT2028-1AN20 Contactor is a robust, 3-pole IEC magnetic contactor engineered for heavy-duty motor control in industrial HVACR and automation systems. Operating with a 220V AC 50/60Hz coil, this SIRIUS S0 frame unit provides reliable switching for 3-phase motors, delivering up to 38A under AC-3 conditions and 50A for AC-1 resistive loads. Its integration into your control panel is streamlined via screw-type terminals and a 35mm DIN rail mounting footprint, ensuring a high-vibration resistant connection in demanding environments. This model features a built-in 1NO+1NC auxiliary contact configuration, allowing for immediate feedback or interlocking without the need for additional add-on blocks. Rated for 18.5 kW at 400V, the 3RT2028-1AN20 is an ideal replacement for legacy 3RT1035 units, maintaining physical compatibility while offering the enhanced mechanical durability of the SIRIUS Innovations line, capable of up to 10 million switching cycles.

Key Benefits

• Versatile Power Control: Rated for 10 HP at 230V and 25 HP at 460V, making it suitable for a wide range of fan, pump, and compressor motors.
• Enhanced Circuit Safety: Integrated 1NO and 1NC auxiliary contacts provide essential signaling and safety interlocking out of the box.
• High Insulation Rating: Features a 690V insulation voltage (Ui) and 6kV surge voltage resistance to protect against electrical transients.
• Optimized Footprint: The compact S0 frame size (approx. 45mm width) maximizes cabinet space while handling high-amperage industrial loads.
• Reliable Termination: Heavy-duty screw terminals ensure secure wire retention and prevent thermal hotspots during continuous operation.

Common Questions

What are the wiring differences when replacing a 3RT10 contactor with this 3RT2 series? The 3RT2028-1AN20 is a direct functional replacement for the 3RT1035 series. While the footprint and mounting are identical, ensure that any side or top-mounted auxiliary blocks from the older series are compatible with the newer SIRIUS Innovations S0 frame before installation. Can this contactor be used with a 208V control circuit? While designed for a 220V AC coil, the coil has a specific operational range. Most Siemens 220V coils will pull in at 208V, but for critical applications with high voltage fluctuations, a dedicated 208V coil is recommended to prevent contact chatter. What is the maximum wire size for the screw terminals on this S0 frame? The main power terminals on this unit are designed to accommodate up to 2 x 10 AWG or 1 x 8 AWG stranded wire, ensuring capacity for the full 50A AC-1 current rating.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.