Thermal overload relay for MC9b-40a series contactor, current 1-1.6A MT-32 7-10A

Thermal Overload Relays – Protection for Motors and Circuits

The MT-32 thermal overload relay is a protective device designed to protect electric motors and circuits from the effects of overloads. This device, based on bimetallic technology, reacts to temperature increases caused by excessive current draw, thereby protecting valuable equipment from damage. The relay can be mounted directly under the contactor or using a dedicated mounting base UZ-63L, providing installation flexibility.

Construction and Application

The MT-32 relay is compatible with LS Electric Metasol series contactors (MC-9b, MC-12b, MC-18b, MC-22b, MC-32a and MC-40a), making it an ideal solution in drive control systems. Thanks to the adjustable tripping threshold, it can be adapted to specific application needs. This relay is used in a wide range of industrial and commercial installations where reliable motor protection is crucial. It is worth noting that this device protects not only against overloads, but also against phase failures, long starting times and motor stalling.

Characteristics and Benefits

• Versatility: The MT-32 relay is available in various current setting ranges (including 1-1.6A and 7-10A), allowing for precise matching to the load characteristics.
• Flexible mounting: The possibility of mounting directly on the contactor or using the dedicated UZ-63L base facilitates installation and servicing.
• Manual and automatic reset: Allows for quick restoration of system operation after removing the cause of the relay tripping.
• Tripping indicator: Allows for easy identification of the cause of the circuit disconnection and quick problem diagnosis.
• Compliance with standards: The relay meets the requirements of IEC/EN 60947-1 and IEC/EN 60947-4-1 standards, guaranteeing its safety and reliability.
• Auxiliary contacts: Equipped with 1NO+1NC auxiliary contacts for relay status signaling and remote control of other devices.
• Durable construction: Ensures long life and trouble-free operation in harsh industrial conditions (operating temperature: -5…60°C).
• IP20 protection class: Protection against touching fingers and solid objects with a diameter greater than 12mm.

Additionally, it is worth mentioning the possibility of setting the relay in class 10 or 20 characteristics – the choice of the appropriate class depends on the type of load and application requirements. Class 10 provides a faster response to overloads, while class 20 is more suitable for loads with high inrush current.