Schneider Electric LR3D08 Thermal Iec Overload Relay

Product Description

The SCHNEIDER ELECTRIC LR3D08 is a thermal IEC overload relay rated for 2.5 to 4 amps and up to 690 VAC. It protects three-phase and single-phase motor circuits from sustained overload conditions by interrupting the control circuit when excess current causes a bimetallic element to trip. The relay is rated Trip Class 10A, meaning it trips within 10 seconds or less under a defined overload multiple. Licensed electricians and industrial controls technicians install this relay as part of a motor starter assembly in panel boards, motor control centers, and equipment enclosures.

The LR3D08 is designed for use in motor control applications where IEC-standard components are specified. It pairs directly with LC1D09 through LC1D38 series contactors, making it appropriate for residential mechanical rooms, light commercial rooftop units, pump panels, and industrial motor control assemblies. Its thermal sensing method responds to true current-based heating rather than electronic sampling, providing reliable overload protection without external power requirements.

Key Features

• Thermal sensing method provides inherent overload detection based on actual current-induced heating
• Trip Class 10A rating for fast response to sustained overload conditions
• Operating range of 2.5 to 4 amps covers a broad range of small motor applications
• Rated to 690 VAC for compatibility with both North American and international supply voltages
• Direct mount design mates with LC1D09 to LC1D38 contactors without separate wiring
• Compact form factor suited for installation in tight panel enclosures

Compatibility

Designed for direct use with LC1D09 and LC1D38 series contactors as stated by the manufacturer.

Installation Notes

Installation should be performed by a qualified electrician in accordance with the National Electrical Code (NEC) and any applicable local codes. De-energize and lock out the panel or motor control center before mounting or wiring this relay. Verify that the connected motor full-load amperage falls within the 2.5 to 4 amp adjustment range before placing the circuit in service. Do not bypass the overload relay or defeat the trip mechanism during commissioning.