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Siemens Overload Relay: Thermal Protection, 3 Poles, 1NO/1NC, Frame Size S2 - IEC Thermal Overload Relays
SiemensIEC Thermal Overload Relays

Siemens Overload Relay: Thermal Protection, 3 Poles, 1NO/1NC, Frame Size S2

The SIEMENS Overload Relay: Thermal Protection (SKU 499K17, MPN 3RU21364FB0) is an IEC thermal overload relay with a Frame Size S2, rated for 28 A – 40 A and a maximum voltage of 690V AC. It features 1NO/1NC…

SKU 3G-OTH-41745

Brand
Siemens
Item
Overload Relay: Thermal Protection, 3 Poles, 1NO/1NC, Frame Size S2
Category
IEC Thermal Overload Relays
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Technical Specifications

Siemens
Manufacturer Part Number
3RU21364FB0
Type
1NO/1NC, Frame Size S2, 28 A – 40 A
Poles
3
Frame Size
S2
Compatible Contactors
Frame Size S2
Auxiliary Contact Form
1NO/1NC
Maximum Voltage Rating
690V AC
Phase Loss Sensitivity
No
Thermal Units Required
None (Relay Includes Integrated Bimetallic Elements)
Terminal Connection Type
Screw Terminals
Compatible Contactor Series
SIRIUS
View Full Spec Sheet

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

Product Description

The SIEMENS Overload Relay: Thermal Protection (SKU 499K17, MPN 3RU21364FB0) is an IEC thermal overload relay with a Frame Size S2, rated for 28 A – 40 A and a maximum voltage of 690V AC. It features 1NO/1NC auxiliary contacts, screw terminals, and integrated bimetallic elements, eliminating the need for separate thermal units. This relay is compatible with SIRIUS contactors of Frame Size S2 and does not include phase loss sensitivity.

Frequently Asked Questions

What is the SIEMENS 3RU21364FB0 overload relay used for?

The SIEMENS 3RU21364FB0 overload relay provides thermal protection for motors in industrial applications. It is designed for use with SIRIUS contactors of Frame Size S2, protecting against overload conditions by using integrated bimetallic elements. Common applications include pumps, conveyors, and fans in manufacturing and process industries.

What are the specifications of the SIEMENS 3RU21364FB0 overload relay?

The SIEMENS 3RU21364FB0 is an IEC thermal overload relay with Frame Size S2, rated for 28 A – 40 A and a maximum voltage of 690V AC. It features 1NO/1NC auxiliary contacts, screw terminals, and integrated bimetallic elements. It does not include phase loss sensitivity and is compatible with SIRIUS contactors of Frame Size S2.

Where to buy the SIEMENS 3RU21364FB0 overload relay worldwide?

You can source the SIEMENS 3RU21364FB0 overload relay from 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 provide competitive pricing and reliable sourcing for this Siemens thermal overload relay.

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

To select the correct SIEMENS overload relay, match the relay's current range (e.g., 28 A – 40 A for the 3RU21364FB0) to the motor's full-load current. Ensure the frame size (S2) is compatible with your SIRIUS contactor. Verify voltage rating (690V AC) and auxiliary contact configuration (1NO/1NC). For motors requiring phase loss protection, choose a model with that feature.

Used in

Common applications for Siemens
District cooling plants — LME73 + RWF55 for condenser-water modulation
Inflight catering and food-processing steam boilers — LMG22 with SQN90 air-fuel cross-damper
Hospital steam-plant redundancy — LME41 with QRA2 UV flame detection for dual-fuel boilers
Semiconductor fab process heat — LME23 and SKP55 gas valves on hot-oil heater skids
Container-terminal reefer-deck heating — LMG22 retrofit onto legacy burner racks

Siemens Products

3G Electric supplies Siemens 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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SIEMENS Overload Relay: Thermal Protection, 3 Poles, 1NO/1NC, Frame Size S00, 0.35 A – 0.5 A (MPN 3RU21160FB0). Key specifications — Brand: SIEMENS; Auxiliary Contact Form: 1NO/1NC; Compatible Contactor Series: SIRIUS; Terminal Connection Type: Screw Terminals; Frame Size: S00; Maximum Voltage Rating: 690V AC; Phase Loss Sensitivity: No; Thermal Units Required: None (Relay Includes Integrated Bimetallic Elements).