Schneider Electric LRD21 | TeSys LRD Thermal Overload Relay 12-18A Class 10A
Schneider Electric LRD21 (TeSys LRD) thermal overload relay. 12-18A adjustable range, Class 10A trip, 690V AC, 1NO+1NC contacts. For motor protection with LC1D contactors.
Product Overview
The Schneider Electric LRD21 is a thermal overload relay from the TeSys LRD series (also known as TeSys Deca). It provides motor protection (overload, phase unbalance) for 3-phase AC motors in the 12–18 A full load current range. Designed for direct mounting under TeSys D contactors (e.g., LC1D18 to LC1D38), it features ambient temperature compensation, manual reset, and a compact form factor for industrial control panels.
Technical Specifications (Electrical & Protection)
| Parameter | Specification |
| Manufacturer / Series | Schneider Electric / TeSys LRD (Deca) |
| Model / Part Number | LRD21 |
| Product Type | Thermal Overload Relay (Differential, Bi-metallic) |
| Rated Operational Voltage (Ue) | 690 V AC (50/60 Hz, 0–400 Hz range) |
| Current Setting Range (Ir) | 12 – 18 A (Adjustable via dial) |
| Trip Class | Class 10A (per IEC 60947-4-1) |
| Phase Failure Sensitivity | Trips at ~130% Ir on two phases |
| Auxiliary Contacts | 1 NO + 1 NC (Signaling Circuit) |
| Control Circuit Rating | 1.5 A at 240V AC-15; 0.1 A at 250V DC-13 |
Technical Specifications (Mechanical & Environmental)
| Parameter | Specification |
| Compatible Contactors | LC1D18, LC1D25, LC1D32, LC1D38 (TeSys D) |
| Mounting | Direct under contactor, DIN rail, or plate |
| Connection Type | Screw Clamp Terminals |
| Terminal Wire Range | Power: 1.5–10 mm²; Control: 1–2.5 mm² |
| Dimensions (W×H×D) | 45 × 66 × 70 mm |
| IP Rating | IP20 |
| Operating Temperature | -20 °C to +60 °C (with compensation) |
| Reset Type | Manual (Blue push-button), Red stop button |
Key Features
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Class 10A Tripping: Fast response (≈10 seconds) at 7.2× Ir for motor stall protection.
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Ambient Compensation: Maintains trip accuracy across -20°C to +60°C environments.
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Visual Trip Indication: Clear flag/button indication for quick fault diagnosis.
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Screw Clamp Reliability: Robust terminals for power and control wiring.
Applications
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Protection of 3-phase AC motors (pumps, fans, conveyors)
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Industrial machine control panels
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Motor starter combinations with TeSys D contactors
About ACH
Founded in 2012, ACH is a top-tier distributor of industrial automation products, supplying genuine devices from leading brands like ABB, P+F, E&H, AB, MTL to emerging markets worldwide. Our mission is to provide 100% Genuine products at the most competitive prices, helping customers reduce costs and strengthen their market position.
Frequently Ask & Questions
Are preferential prices available?
Long-term brand partners can get competitive product prices. At the same time, ACH controls the profit per order to 5%, providing the most competitive prices.
Are the Products Genuine OEM Units?
Yes, all products from ACH are certified genuine OEM units. We acquire our inventory through official OEM channels and trusted third-party suppliers, ensuring every item is authentic and reliable.
How will you arrange shipment?
We'll handle the shipping for you. Through our partnerships, we can secure competitive rates with major carriers like FedEx, DHL, TNT, and UPS, ensuring a smooth and cost-effective delivery.
What is the warranty of goods?
One-year Warranty.
How long is the logistics cycle of the product?
Products are divided into spot and futures, and the delivery period of different brands of products is also different. For details, please contact the ACH business manager.
