Overview
The Siemens 3UA5400-2D overload relay is a solid state thermal protection device engineered for industrial motor control applications. Rated for 20–32A AC operation, this relay integrates seamlessly with Siemens 3TF contactors, providing dependable overload detection and motor winding protection in machinery and plant automation systems.
Key Features
- Solid state overload detection with thermal sensing technology
- 1NO/1NC contact configuration for flexible circuit control
- On/off indicator for visual status confirmation
- Designed for direct mounting with 3TF contactor starters
- Adjustable trip settings within 20–32A range
Technical Specifications
The relay operates on AC current and provides reliable motor protection across standard industrial voltage ranges. Its compact footprint and modular design allow for straightforward integration into motor starter assemblies without requiring extensive panel modifications.
Typical Applications
This overload relay is commonly used in:
- Three-phase motor starters and soft-start systems
- Industrial conveyor and pump control circuits
- Machine tool protection and automation platforms
- HVAC compressor and fan motor circuits
- General-purpose equipment requiring 20–32A overload safeguards
Compatibility & Replacements
The 3UA5400-2D is the standard overload relay option for Siemens 3TF46, 3TF47, and related contactor sizes in this current range. When replacing worn or tripped relays, confirm the mounting platform and contact configuration match your existing control circuit. Maintenance technicians should verify amperage settings and contact condition during routine servicing to ensure continued protective operation.
