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Siemens Auxiliary Switch: 1NC, Front Mount - Siemens Auxiliary Contacts
SiemensSiemens Auxiliary Contacts

Siemens Auxiliary Switch: 1NC, Front Mount

The SIEMENS Auxiliary Switch (MPN 3RH1921-1CD01) is a front-mounted auxiliary contact block with a 1NC configuration, designed for Frame Size S0. It is compatible with the SIRIUS 3RT1 contactor series, providing a…

SKU 3G-OTH-38697

Brand
Siemens
Item
Auxiliary Switch: 1NC, Front Mount
Category
Siemens Auxiliary Contacts
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Technical Specifications

Siemens
Manufacturer Part Number
3RH1921-1CD01
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 3RH1921-1CD01) is a front-mounted auxiliary contact block with a 1NC configuration, designed for Frame Size S0. It is compatible with the SIRIUS 3RT1 contactor series, providing a normally closed switching function for control and signaling applications.

Frequently Asked Questions

What is the SIEMENS 3RH1921-1CD01 auxiliary switch used for?

The SIEMENS 3RH1921-1CD01 auxiliary switch provides a normally closed (1NC) contact for control and signaling in industrial automation. It mounts on the front of SIRIUS 3RT1 contactors (Frame Size S0) to monitor contactor status or interlock circuits in motor control panels.

What are the specifications of the SIEMENS 3RH1921-1CD01?

The SIEMENS 3RH1921-1CD01 is a front-mounted auxiliary contact block with 1NC configuration. It is designed for Frame Size S0 and is compatible with the SIRIUS 3RT1 contactor series. The manufacturer part number is 3RH1921-1CD01.

Where to buy the SIEMENS 3RH1921-1CD01 worldwide?

3G Electric supplies the SIEMENS 3RH1921-1CD01 auxiliary switch to customers worldwide. We handle full logistics, customs clearance, and delivery to your site. Contact us for a quote and lead time on this genuine Siemens component.

How to install the SIEMENS 3RH1921-1CD01 auxiliary switch?

Install the SIEMENS 3RH1921-1CD01 by clipping it onto the front of a SIRIUS 3RT1 contactor (Frame Size S0). Ensure the contactor is de-energized and locked out. The 1NC contact wiring should follow the manufacturer's terminal diagram for proper control circuit integration.

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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