TF42-20 Thermal overload relay 1SAZ721201R1049

Thermal overload relay – reliable motor protection

The TF42-20 thermal overload relay is a key element in protecting electric motors from overload and phase failure effects. The device is designed to work with AF contactors, providing comprehensive protection in industrial and commercial installations. Thanks to its construction and functionality, it transmits information about the circuit status, enabling a quick response in the event of problems.

Construction and principle of operation

The TF42-20 relay uses a bimetallic measuring element that reacts to temperature changes caused by current flow. If the set current value is exceeded, the bimetallic element triggers a disconnecting mechanism, protecting the motor from damage. The device offers both automatic and manual reset options, increasing its flexibility. Additionally, it has built-in auxiliary contacts (1NO + 1NC) for signaling the operating status and a testing and stopping function.

Key features and benefits

• Wide current setting range: Adjustment in the range of 16-20A allows for precise matching to the characteristics of the protected motor.
• High reliability: Class 10 release ensures a quick and effective response to overloads.
• Phase failure protection: Built-in phase failure detection function minimizes the risk of motor damage in case of incorrect power supply.
• Temperature compensation: Ensures stable operation in various environmental conditions (-25°C to +60°C).
• Easy installation: Designed for direct mounting on AF contactors, simplifying installation and integration with the existing system.
• Multifunctionality: The ability to choose automatic or manual reset and the presence of auxiliary contacts increase the functionality of the device.
• Safety: The ability to seal the cover protects against unauthorized changes to settings.
• Versatility: The relay is compatible with a wide range of three-phase and single-phase motors with a rated voltage of up to 690V AC/DC.

Applications

The TF42-20 relay is used in:

• Protection of electric motors in industrial installations (e.g., pumps, fans, compressors).
• Building and industrial automation systems.
• Electrical switchboards as an element of motor circuit protection.
• Applications requiring reliable protection against overloads and phase failures.
• Machines and equipment requiring high availability and minimizing downtime caused by motor failures.

Thanks to its solid construction and advanced functions, the TF42-20 relay is an optimal solution for professionals looking for reliable protection of electric motors in demanding working conditions.