Thermal overload relay for MC500a-800a series contactor, current 260-400A MT-800 260-400A

Motor and Circuit Protection – Thermal Relay MT-800

The MT-800 thermal relay is a reliable device designed to protect electric motors and circuits from overload. Designed to work with LS MC-500a to MC-800a series contactors, it is a key element of the protection system in industrial and commercial applications. Its construction based on the bimetallic principle ensures an effective response to temperature increase caused by overload, minimizing the risk of damage to connected devices.

Construction and functionality

The MT-800 relay uses a 3-element heater system (non-differential), which means its operation does not depend on the load distribution between phases. This ensures stable and precise protection even in the event of load asymmetry. The possibility of resetting – both manual and automatic – increases the flexibility of use and adapts to different application needs. Built-in screw terminals facilitate connection of wires, and mounting directly on the contactor provides a compact solution and simplifies installation.

Key features and benefits

• Wide current range: The MT-800 relay supports currents in the range of 260-400A, making it a universal solution for various applications.
• Compatibility with LS Contactors: It has been specifically designed to work with LS MC-500a to MC-800a series contactors, guaranteeing optimal performance and reliability.
• Multifunctionality: It has status indicators (stop, test, trip) that inform about the current state of the device and facilitate diagnostics of any problems. An additional auxiliary contact 1NO+1NC allows integration with control and signaling systems.
• Durability and reliability: Operation in a wide range of ambient temperatures (-25…60°C) and compliance with CCC, CSA, UL and CE standards confirm the high quality of workmanship and reliability of the device in various working conditions.
• Solid construction: Dimensions 360mm x 530mm x 212mm and weight 11.5kg testify to the solid construction of the relay, ensuring its durability even in harsh industrial conditions.
• Universal power supply: Support for AC 690VAC voltage at 50/60Hz frequency ensures compatibility with most electrical installations.