Overview
The Siemens 3RB2056-1FW2 is an IEC-rated solid-state electronic overload relay designed for robust three-phase motor protection. This relay is used for the protection of three-phase motors and reliably protects loads as well as other switching and protective devices in the respective load feeder against overload, phase asymmetry and phase failure. The unit features an adjustable current range of 50–200A with 1 NC and 1 NO auxiliary contact, Class 10 trip classification, and automatic reset function.
Key Features
- Adjustable current range 50–200A for flexible motor sizing
- Three-pole design with 1 NO and 1 NC auxiliary contacts offering comprehensive protection against overload conditions
- Class 10 trip class with automatic reset capability
- Suitable for motors requiring 100–1000 volts
- Manual and automatic reset features for versatile application and easy integration with screw connections
- Solid-state design for direct mounting to contactor or stand-alone installation with pass-through current transformers
Technical Specifications
This Size S6 relay features bar-type current transformer connections and screw terminals. The unit operates with 1000 VAC supply voltage and operates effectively in operating temperature environments from 60°C down to −25°C.
Typical Applications
- Three-phase motor overload protection in industrial machinery
- Pump and fan motor protection systems
- Compressor and air handling unit protection
- General industrial automation and manufacturing equipment
- Stand-alone and contactor-mounted motor protection circuits
Compatibility & Replacements
The 3RB2056-1FW2 is compatible with 3-pole contactors including 3RT1054, 3RT1055, and 3RT1056 models that feature pass-through current transformer connections. This relay is part of Siemens’ SIRIUS motor control product line and integrates seamlessly with matching Size S6 contactor assemblies. For applications requiring different amperage ranges or trip characteristics, consult Siemens’ complete SIRIUS overload relay portfolio.
