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Siemens Auxiliary Switch: 1NO, Front Mount - Siemens Auxiliary Contacts
SiemensSiemens Auxiliary Contacts

Siemens Auxiliary Switch: 1NO, Front Mount

The SIEMENS Auxiliary Switch (MPN 3RH1921-1CD10) is a front-mounted auxiliary contact block with one normally open (1NO) contact, designed for Frame Size S0. It is compatible with the SIRIUS 3RT1 contactor series…

SKU 3G-OTH-38667

Brand
Siemens
Item
Auxiliary Switch: 1NO, Front Mount
Category
Siemens Auxiliary Contacts
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Technical Specifications

Siemens
Manufacturer Part Number
3RH1921-1CD10
Frame Size
S0
Compatible with Series
SIRIUS 3RT1 Contactors
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Siemens Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The SIEMENS Auxiliary Switch (MPN 3RH1921-1CD10) is a front-mounted auxiliary contact block with one normally open (1NO) contact, designed for Frame Size S0. It is compatible with the SIRIUS 3RT1 contactor series, providing a single switching function for control and signaling applications.

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 siemens auxiliary contacts. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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