Schneider Thermal Overload Relay LRD04

Schneider Electric TeSys Deca 0.4‑0.63A Thermal Overload Relay LRD04

Schneider Thermal Overload Relay LRD04 — Precise Protection for Small Three-Phase Motors

The Schneider Thermal Overload Relay LRD04 is a compact, dependable motor protection device from Schneider Electric’s trusted TeSys LRD series. Designed to offer thermal overload protection for smaller three-phase motors, this relay helps prevent motor overheating, phase loss issues, and unbalanced load conditions — improving reliability and safety in electrical control systems across industrial, commercial, and workshop applications in India.

🔌 What Is the Schneider LRD04 Thermal Overload Relay?

The LRD04 is a three-pole thermal overload relay with an adjustable current protection range of 0.4 – 0.63 A, engineered to monitor current through all three phases of a motor circuit and disconnect the motor before damage occurs when sustained overload or phase faults are detected. Its compact design makes it a practical choice for motor starter assemblies paired with contactors such as LC1D09, LC1D12, LC1D18, LC1D25, LC1D32, and LC1D38.

This overload relay conforms to Class 10A tripping standards, balancing tolerance for normal motor inrush currents with reliable response to prolonged overload conditions — in line with IEC motor protection norms.

🛠️ Key Features & Benefits

• Adjustable Thermal Protection (0.4 – 0.63 A) — Customise the overload range to precisely match the full-load current (FLC) of small motors.

• Three-Pole Monitoring — Continuously checks all phases to detect overload, phase loss, and unbalanced load conditions.

• Class 10A Trip Characteristic — Offers dependable overload tripping while tolerating brief start-up inrush currents.

• Auxiliary Contacts (1NO + 1NC) — Provides signalling for fault conditions, suitable for control panels or automation systems.

• Manual/Automatic Reset & Test Buttons — Allows flexible operation and easy functional testing without powering down.

• Secure Screw-Clamp Terminals — Ensures reliable, vibration-resistant electrical connections during operation.

• Compact Industrial Build — Easily mounts beneath compatible contactors or on DIN rail/panel for space-efficient motor starter design.

• Wide Operating Range — Rated for up to 690 V AC and 0-400 Hz, suited for varied motor control environments.

⚙️ Why Choose the LRD04 Overload Relay?

Thermal overload relays like the LRD04 are essential components in electrical motor protection systems. They help you:

• Prevent motor winding damage due to prolonged overcurrent and overheating

• Reduce unplanned downtime from motor failures

• Enhance system safety with reliable fault detection and trip control

• Extend motor and equipment lifespan through dependable thermal protection

• Integrate seamlessly with Schneider contactors in compact starter assemblies

Whether you are designing new motor control systems or upgrading existing panels, the LRD04 adds an effective layer of protection to safeguard valuable equipment.

📌 Typical Applications

• Motor starter panels and control cabinets

• Small pumps, fans & compressors

• Conveyor and material handling systems

• HVAC motor control applications

• Automated production machinery

• Electrical control systems requiring compact motor overload protection