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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 (MPN 3RU21364HB0) is an IEC thermal overload relay with a Frame Size S2, designed for use with SIRIUS contactors of the same frame size. It features 1NO/1NC auxiliary…

SKU 3G-OTH-42153

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
3RU21364HB0
Type
1NO/1NC, Frame Size S2, 40 A – 50 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
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Siemens Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The SIEMENS Overload Relay: Thermal Protection (MPN 3RU21364HB0) is an IEC thermal overload relay with a Frame Size S2, designed for use with SIRIUS contactors of the same frame size. It features 1NO/1NC auxiliary contacts, screw terminals, and a maximum voltage rating of 690V AC. The relay includes integrated bimetallic elements, eliminating the need for separate thermal units, and does not offer phase loss sensitivity.

Frequently Asked Questions

What is the SIEMENS 3RU21364HB0 overload relay used for?

The SIEMENS 3RU21364HB0 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 in manufacturing, HVAC, and pumping systems.

What are the specifications of the SIEMENS 3RU21364HB0 overload relay?

The SIEMENS 3RU21364HB0 is an IEC thermal overload relay with Frame Size S2, 3 poles, 1NO/1NC auxiliary contacts, screw terminals, and a maximum voltage rating of 690V AC. It includes integrated bimetallic elements, so no separate thermal units are needed. It does not offer phase loss sensitivity.

Where to buy the SIEMENS 3RU21364HB0 overload relay worldwide?

You can source the SIEMENS 3RU21364HB0 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.

How to select the correct SIEMENS overload relay for a SIRIUS contactor?

To select the correct SIEMENS overload relay, match the frame size of the relay to the SIRIUS contactor. The 3RU21364HB0 is Frame Size S2 and includes integrated bimetallic elements. Ensure the current range (40 A – 50 A) and auxiliary contact configuration (1NO/1NC) meet your motor protection requirements.

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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