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SCHNEIDER Overload Relay: Thermal Protection, 3 Poles, 1NO/1NC, Phase Loss Sensitivity - IEC Thermal Overload Relays
SCHNEIDERIEC Thermal Overload Relays

SCHNEIDER Overload Relay: Thermal Protection, 3 Poles, 1NO/1NC, Phase Loss Sensitivity

The SCHNEIDER Overload Relay: Thermal Protection (SKU 3G-OTH-40535, MPN LRD21) is a 3-pole IEC thermal overload relay with integrated bimetallic elements, rated for 12 A – 18 A and a maximum voltage of 690V AC. It…

SKU 3G-OTH-40535

Also listed as: LRD 21 · LRD-21

Brand
SCHNEIDER
Item
Overload Relay: Thermal Protection, 3 Poles, 1NO/1NC, Phase Loss Sensitivity
Category
IEC Thermal Overload Relays
Available to Order
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Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Delivery
Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment
Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to
Singapore

Technical Specifications

SCHNEIDER
Manufacturer Part Number
LRD21
Type
1NO/1NC, Phase Loss Sensitivity, 12 A – 18 A
Poles
3
Compatible Contactors
TeSys Deca (18 to 38 Amp Models)
Auxiliary Contact Form
1NO/1NC
Maximum Voltage Rating
690V AC
Phase Loss Sensitivity
Yes
Thermal Units Required
None (Relay Includes Integrated Bimetallic Elements)
Terminal Connection Type
Screw Clamp Terminals
Compatible Contactor Series
TeSys Deca

Technical Documents

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SCHNEIDER Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The SCHNEIDER Overload Relay: Thermal Protection (SKU 3G-OTH-40535, MPN LRD21) is a 3-pole IEC thermal overload relay with integrated bimetallic elements, rated for 12 A – 18 A and a maximum voltage of 690V AC. It features a 1NO/1NC auxiliary contact form, screw clamp terminals, and phase loss sensitivity. This relay is compatible with TeSys Deca contactors (18 to 38 Amp models) and requires no external thermal units.

Frequently Asked Questions

What is the SCHNEIDER LRD21 overload relay used for?

The SCHNEIDER LRD21 overload relay provides thermal protection for three-phase motors by monitoring current and preventing overheating. It is used in industrial motor control applications, compatible with TeSys Deca contactors (18 to 38 Amp models), and includes phase loss sensitivity for enhanced motor protection.

What are the specifications of the SCHNEIDER LRD21 overload relay?

The SCHNEIDER LRD21 is a 3-pole IEC thermal overload relay rated for 12 A to 18 A with a maximum voltage of 690V AC. It features a 1NO/1NC auxiliary contact form, screw clamp terminals, integrated bimetallic elements, and phase loss sensitivity. It is compatible with TeSys Deca contactors and requires no external thermal units.

Where to buy the SCHNEIDER LRD21 overload relay worldwide?

You can source the SCHNEIDER LRD21 overload relay through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to worldwide destinations. Contact us for availability and lead time; we supply genuine SCHNEIDER components for motor protection applications.

How to select the correct SCHNEIDER overload relay for a motor?

To select the correct SCHNEIDER overload relay, match the relay's current range (e.g., 12 A to 18 A for LRD21) to the motor's full-load current. Ensure compatibility with your contactor series, such as TeSys Deca. Verify voltage rating (690V AC) and required features like phase loss sensitivity. Consult the motor nameplate and application needs.

Used in

Common applications for SCHNEIDER
Motor starting in conveyor systems — Schneider Altistart ATS 22 soft starters (e.g., ATS22D17S6U) reduce inrush current.
Speed control for industrial pumps — Schneider Altivar ATV320 VFDs (e.g., ATV320U55N4W) provide variable flow regulation.
Machine safety interlocking — Schneider XPSUAF13AP safety relays monitor emergency stop circuits on assembly lines.
Panel-mounted control stations — Schneider XB5 flush push buttons (ZB5AA5) serve as start/stop operators in MCCs.
Heavy-duty motor switching — Schneider LC1G150LSEA contactors handle 150 A loads in compressor and crusher applications.
Emergency stop actuation — Schneider 9001K mushroom-head push buttons (9001KR25R) provide red, momentary stop functions.

SCHNEIDER Products

3G Electric supplies SCHNEIDER iec thermal overload relays. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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