Siemens 3RT2028-1FB4 AC Contactor

Description

Siemens 3RT2028-1FB4 AC Contactor

Product Dimensions：

The Siemens 3RT2028-1FB4 is a high-performance power contactor from the SIRIUS Innovation range. It is specifically designed for switching motors and resistive loads in industrial environments where reliability and a compact footprint are essential.

Product Detailed Description

The 3RT2028-1FB4 is a 3-pole, Size S0 contactor. It is equipped with a DC-operated coil that includes an integrated varistor to suppress surge voltages, making it safe for use with sensitive electronic controllers like PLCs. The “SIRIUS” modular system allows for easy attachment of auxiliary switches, function modules, and thermal overload relays.

Technical Parameters

Product Advantages

• Energy Efficiency: The DC coil is optimized for low power consumption, reducing the heat load within the control cabinet.
• Integrated Protection: The built-in varistor protects the upstream PLC or electronic control circuit from voltage spikes caused by the contactor coil’s de-energization.
• Modular Versatility: Part of the SIRIUS Innovation system, meaning it shares accessories (links, auxiliary blocks, timers) with other Siemens motor starter components.
• High Performance-to-Size Ratio: Provides 18.5 kW of power switching in a very slim, space-saving S0 frame (45mm width).

Important Considerations & Precautions

• Coil Polarity: Since this is a DC-operated model (1FB4), ensure that the 24V DC supply is connected with the correct polarity to terminals A1 (+) and A2 (-).
• Mounting Position: While it can be mounted on a standard 35mm DIN rail, if mounted on a vertical surface, a maximum inclination of \pm 22.5^\circ is recommended to ensure mechanical reliability.
• Ambient Temperature: In high-density cabinets, ensure adequate ventilation. The rated performance is valid up to 60°C; derating may be required for higher temperatures.
• Short-Circuit Protection: This contactor must be protected by a coordinated fuse or circuit breaker (Type 1 or Type 2 coordination) to prevent welding of the contacts during a fault.

Product Applications

The 3RT2028-1FB4 is versatile across many industrial sectors:

• Motor Control: Starting and stopping 3-phase induction motors up to 18.5 kW (e.g., pumps, fans, compressors).
• Conveyor Systems: Frequent switching of drive motors in logistics and material handling.
• Resistive Loads: Controlling heating elements or industrial lighting banks (AC-1 duty).
• PLC Interfacing: Direct control from 24V DC transistor outputs of a PLC without the need for an intermediate coupling relay.

Shipping Port: Xiamen, China

Payment: Bank of Chicago, Bank of Singapore

Express cooperation: fedex, DHL, UPS and your express account

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