Schneider Electric LR3D3559 Thermal Iec Overload Relay

Product Description

The SCHNEIDER ELECTRIC LR3D3559 is a thermal IEC overload relay rated for 48 to 65 amps and up to 690 VAC. It protects three-phase motor circuits from sustained overcurrent conditions by sensing heat buildup through a bimetallic thermal element. When current exceeds the set range, the relay trips and interrupts the control circuit before motor winding damage occurs. This unit is rated Trip Class 20, meaning it trips within 20 seconds at 7.2 times the full-load current setting. Licensed electricians and industrial controls technicians install this relay as part of a motor starter assembly in commercial and industrial applications.

The LR3D3559 is designed for use with LC1D80 and LC1D95 IEC contactors, making it a direct add-on component in motor starter assemblies. Typical applications include three-phase motor protection in commercial HVAC equipment, pumping systems, conveyor drives, and industrial machinery. It is suited for installations where IEC-standard motor control components are specified and where Trip Class 20 timing is required for motors with longer acceleration profiles.

Key Features

• Thermal sensing method detects sustained overcurrent without electronic components
• 48 to 65 amp adjustment range covers a wide span of motor full-load amp ratings
• Trip Class 20 rating accommodates motors with extended startup times
• 690 VAC rating supports use in higher-voltage three-phase distribution systems
• Designed to mount directly onto LC1D80 and LC1D95 contactors without additional hardware

Compatibility

Designed for use with LC1D80 and LC1D95 IEC contactors as stated by the manufacturer.

Installation Notes

Installation should be performed by a licensed electrician in accordance with the NEC and any applicable local codes. De-energize and lock out the circuit before mounting or wiring the relay. Set the current adjustment dial to match the motor nameplate full-load amp rating after installation. Do not exceed the 690 VAC voltage rating of the relay.