Schneider Thermal Overload Relay LRD380

Schneider Electric TeSys Deca 62‑80A 3 Pole Thermal Overload Relay (LRD380) — Industrial-Grade Thermal Motor Protection

The Schneider Thermal Overload Relay LRD380 is a heavy-duty motor protection device from the Schneider Electric TeSys LRD series, engineered to safeguard medium-to-large three-phase motors and electrical systems. Designed for industrial and commercial control panels, this relay helps prevent motor damage due to prolonged overcurrent, phase loss, and load imbalance — ensuring reliable operation and improved system safety in critical electrical applications.

🔌 What Is the Schneider LRD380 Thermal Overload Relay?

The LRD380 is a three-pole differential thermal overload relay with a wide adjustable current range of 62 – 80 A, suitable for protecting larger three-phase motors up to approximately 37 kW at 400 V AC. It is built to be used with Schneider TeSys contactors like LC1D80/LC1D95 or similar, forming part of a complete motor starter assembly to protect equipment in industrial motor control systems.

This relay uses a bimetallic thermal sensing mechanism to detect excessive current flow and trips the circuit if overload persists — helping safeguard motor windings and reduce the risk of mechanical failure.

🔧 Key Features & Benefits

• Adjustable Thermal Protection (62 – 80 A) — Dial-set current range lets you match the relay precisely to the full-load current (FLC) of your motor.

• Class 10A Trip Characteristic — Offers balanced trip response that tolerates normal motor inrush currents while reacting quickly to sustained overloads.

• Three-Pole Design — Monitors all three phases for balanced operation and overload detection.

• Phase Loss & Unbalance Detection — Provides protection against dangerous phase faults and helps prevent motor damage.

• Manual/Automatic Reset & Test Functions — Offers flexible reset behaviour and allows easy operational checks without disconnecting power.

• Auxiliary Contacts (1NO + 1NC) — Supports signalling or integration with control and automation systems.

• Secure EverLink BTR Screw Terminals — Ensures vibration-resistant wiring and reliable installation.

• DIN Rail/Panel Mounting — Compatible with standard control panel layouts and can mount directly or with terminal blocks.

⚙️ Why Use the LRD380 Overload Relay?

Thermal overload relays like the Schneider LRD380 act as essential safeguards in industrial motor control systems. By detecting sustained overcurrent levels and phase abnormalities, this relay:

• Protects motors from overheating and winding damage

• Reduces unplanned downtime and repair costs

• Increases overall electrical system safety

• Enhances longevity of motors and associated equipment

This makes the LRD380 a reliable choice for environments where motor reliability and protection are critical — such as manufacturing plants, processing lines, HVAC systems, and industrial pumps.

📌 Typical Applications

• Industrial motor starter panels

• Conveyor systems and material handling equipment

• Large HVAC blowers and ventilation motors

• Pumps and compressors in industrial settings

• Commercial electrical switchgear requiring robust overload protection

Whether you are designing a new control system or upgrading an existing one, the LRD380 adds a vital layer of motor protection and operational reliability.