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Siemens Auxiliary Switch: 1NO/1NC, Side Mount - Siemens Auxiliary Contacts
SiemensSiemens Auxiliary Contacts

Siemens Auxiliary Switch: 1NO/1NC, Side Mount

The SIEMENS Auxiliary Switch (MPN 3RH1921-1KA11) is a side-mounted auxiliary contact block with a 1NO/1NC contact configuration, designed for Frame Size S0. It is compatible with the SIRIUS 3RT1 contactor series…

SKU 3G-OTH-38217

Brand
Siemens
Item
Auxiliary Switch: 1NO/1NC, Side Mount
Category
Siemens Auxiliary Contacts
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Technical Specifications

Siemens
Manufacturer Part Number
3RH1921-1KA11
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 3RH1921-1KA11) is a side-mounted auxiliary contact block with a 1NO/1NC contact configuration, designed for Frame Size S0. It is compatible with the SIRIUS 3RT1 contactor series, providing additional switching functionality for industrial control applications.

Frequently Asked Questions

What is the SIEMENS Auxiliary Switch 3RH1921-1KA11 used for?

The SIEMENS Auxiliary Switch 3RH1921-1KA11 is used to add extra switching contacts to SIRIUS 3RT1 contactors in industrial control panels. It provides a 1NO/1NC configuration for signaling, interlocking, or control logic in motor starters and automation systems.

What are the specifications of the SIEMENS 3RH1921-1KA11 auxiliary switch?

The SIEMENS 3RH1921-1KA11 is a side-mounted auxiliary contact block with 1 normally open and 1 normally closed contact. It is designed for Frame Size S0 and is compatible with the SIRIUS 3RT1 contactor series. The manufacturer part number is 3RH1921-1KA11.

Where to buy the SIEMENS 3RH1921-1KA11 auxiliary switch worldwide?

You can source the SIEMENS 3RH1921-1KA11 auxiliary switch worldwide through 3G Electric. As a global industrial equipment distributor, 3G Electric handles full logistics, customs clearance, and delivery to your location, ensuring a smooth procurement process for this Siemens component.

How to install the SIEMENS 3RH1921-1KA11 auxiliary switch?

To install the SIEMENS 3RH1921-1KA11, mount it on the side of a compatible SIRIUS 3RT1 contactor (Frame Size S0). Ensure the contactor is de-energized, snap the auxiliary block into the designated slot, and wire the 1NO and 1NC terminals according to your control circuit diagram.

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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