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Siemens Overload Relay: Thermal Protection, 3 Poles, 1NO/1NC, Frame Size S0 - IEC Thermal Overload Relays
SiemensIEC Thermal Overload Relays

Siemens Overload Relay: Thermal Protection, 3 Poles, 1NO/1NC, Frame Size S0

The SIEMENS Overload Relay: Thermal Protection (MPN 3RU21264CB0) is an IEC thermal overload relay in Frame Size S0, designed for use with SIRIUS contactors of the same frame size. It features integrated bimetallic…

SKU 3G-OTH-40713

Brand
Siemens
Item
Overload Relay: Thermal Protection, 3 Poles, 1NO/1NC, Frame Size S0
Category
IEC Thermal Overload Relays
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Technical Specifications

Siemens
Manufacturer Part Number
3RU21264CB0
Type
1NO/1NC, Frame Size S0, 17 A – 22 A
Poles
3
Frame Size
S0
Compatible Contactors
Frame Size S0
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 3RU21264CB0) is an IEC thermal overload relay in Frame Size S0, designed for use with SIRIUS contactors of the same frame size. It features integrated bimetallic elements, screw terminals, and a 1NO/1NC auxiliary contact form, with a maximum voltage rating of 690V AC. This relay does not include phase loss sensitivity and requires no separate thermal units.

Frequently Asked Questions

What is the SIEMENS 3RU21264CB0 overload relay used for?

The SIEMENS 3RU21264CB0 is an IEC thermal overload relay used to protect motors from overload conditions. It is designed for use with SIRIUS contactors of Frame Size S0 in industrial automation and motor control applications, providing reliable thermal protection via integrated bimetallic elements.

What are the specifications of the SIEMENS 3RU21264CB0 overload relay?

The SIEMENS 3RU21264CB0 is a 3-pole thermal overload relay with Frame Size S0, current range 17 A – 22 A, auxiliary contact form 1NO/1NC, maximum voltage rating 690V AC, screw terminals, and no phase loss sensitivity. It includes integrated bimetallic elements and requires no separate thermal units.

Where to buy the SIEMENS 3RU21264CB0 overload relay worldwide?

You can source the SIEMENS 3RU21264CB0 overload relay worldwide through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to your location. Contact us for availability and lead time.

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., 17 A – 22 A for the 3RU21264CB0) to the motor's full-load current. Ensure the frame size (S0) is compatible with your SIRIUS contactor. Verify voltage rating (690V AC) and auxiliary contact needs (1NO/1NC).

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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