Chint NR2 Thermal Overload Relay

Where to Use NR2 Thermal Overload Relay?

The Chint NR2 Thermal Overload Relay is a thermal overload relay designed to protect three-phase motors from overload and phase failure. It works in conjunction with contactors (such as Chint NC1/NC2/NXC series) to provide complete motor protection in motor control centers, industrial machinery, pump stations, and conveyor systems.

How Does a Thermal Overload Relay Work?

The NR2 uses bimetallic strip technology. When motor current exceeds the set value for a sustained period, the bimetallic strip heats up and bends, triggering the auxiliary contacts to open the contactor coil circuit - safely stopping the motor before damage occurs.

Key Features

• Adjustable Current Setting - Dial adjustment from 0.1A - 630A to match motor FLC
• Phase-Failure Protection - Detects and trips on phase loss (single-phasing) which can burn out motors
• Temperature Compensation - Maintains accurate tripping across ambient temperatures from -25°C to +55°C
• Manual/Auto Reset - Choose immediate restart or require manual intervention after trip
• Direct Mounting - Mounts directly below corresponding contactor for compact installation

Technical Specifications

FAQs

Q: How do I set the overload relay current?

A: Set the dial to match your motor's Full Load Current (FLC) as shown on the motor nameplate. For example, if motor FLC is 12A, set relay to 12A. The relay will trip at approximately 105-120% of this setting.

Q: What's the difference between NR2 and NXR series?

A: NR2 is the classic series with proven reliability. NXR offers enhanced features and modern styling while maintaining compatibility with Chint contactors.