Send a part number, a photo, or a whole BOM — we supply it and stand behind it. Worldwide shipping to 80+ countries.

Siemens Auxiliary Switch: Mfr Part # 3RH2921-1DA11 - Replacement HVACR Controls, Switches & Thermostats
SiemensReplacement HVACR Controls, Switches & Thermostats

Siemens Auxiliary Switch: Mfr Part # 3RH2921-1DA11

SKU 3G-OTH-73655

Brand
Siemens
Item
Auxiliary Switch: Mfr Part # 3RH2921-1DA11
Category
Replacement HVACR Controls, Switches & Thermostats
Available to Order
Trade pricing by quote — replies within 24h
Qty
WhatsApp an engineer
No account needed — your quote request goes straight to our engineers. A free account lets you track quotes and re-order faster.
Worldwide Shipping
Air & sea freight
Datasheet on Request
Technical specs
1-Day Quote
Replies within 24h

Technical Specifications

Siemens
Manufacturer Part Number
3RH2921-1DA11
Product Type
Auxiliary Switch
View Full Spec Sheet

Technical Documents

No technical documents available for this product.
Request documentation
Not sure this is the right part? Get a recommendation.

Need installation or engineering help?

Installation, commissioning, maintenance plans, system design, and bundled product + service quotes — one team handles the full scope.
Talk to an engineer

Ask a question

Siemens Products
3G Electric (S) Pte. Ltd. — Singapore

Frequently Asked Questions

What is the Siemens 3RH2921-1DA11 auxiliary switch used for?

The Siemens 3RH2921-1DA11 auxiliary switch is used in industrial control panels and HVACR systems to provide additional switching contacts for monitoring or signaling the position of contactors and relays. It is commonly applied in motor control centers, conveyor systems, and building automation to ensure reliable status feedback.

What are the specifications of the Siemens 3RH2921-1DA11 auxiliary switch?

The Siemens 3RH2921-1DA11 is an auxiliary switch with manufacturer part number 3RH2921-1DA11. It is designed for use with Siemens contactors and relays in industrial control applications. For detailed electrical ratings and mounting dimensions, refer to the Siemens technical datasheet.

Where to buy the Siemens 3RH2921-1DA11 auxiliary switch worldwide?

You can source the Siemens 3RH2921-1DA11 auxiliary switch through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to worldwide destinations. Contact our team for pricing and lead time on this Siemens replacement HVACR control component.

How to install the Siemens 3RH2921-1DA11 auxiliary switch?

To install the Siemens 3RH2921-1DA11 auxiliary switch, first de-energize the panel. Mount the switch onto the contactor or relay using the provided clips, ensuring proper alignment. Wire the auxiliary contacts according to your control schematic, typically using 24 VDC or 230 VAC circuits. Test operation before restoring power.

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 replacement hvacr controls, switches & thermostats. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

You might also need

Burners & Combustion Pumps & Compressors Spare Parts All Products

Similar products

Matched by specification & description
FURNAS SIEMENS Auxiliary Switch: Mfr Part # 3RH1921-1CA10. Key specifications — Manufacturer Part Number: 3RH1921-1CA10; Product Type: Auxiliary Switch.
FURNAS SIEMENS
FURNAS SIEMENS Auxiliary Switch: Mfr Part # 3RH1921-1CA10. Key specifications — Manufacturer Part Number: 3RH1921-1CA10; Product Type: Auxiliary Switch.
SIEMENS Auxiliary Switch: 2NC, Front Mount, Front-Mounted (MPN 3RH29112NF02). Key specifications — Frame Size: S0; Brand: SIEMENS; Compatible with Series: SIRIUS 3RH2 Contactor Relays.
Siemens
SIEMENS Auxiliary Switch: 2NC, Front Mount, Front-Mounted (MPN 3RH29112NF02). Key specifications — Frame Size: S0; Brand: SIEMENS; Compatible with Series: SIRIUS 3RH2 Contactor Relays.
SIEMENS Auxiliary Switch: 1NO, Front Mount, Front-Mounted (MPN 3RH1921-1CD10). Key specifications — Frame Size: S0; Brand: SIEMENS; Compatible with Series: SIRIUS 3RT1 Contactors.
Siemens
SIEMENS Auxiliary Switch: 1NO, Front Mount, Front-Mounted (MPN 3RH1921-1CD10). Key specifications — Frame Size: S0; Brand: SIEMENS; Compatible with Series: SIRIUS 3RT1 Contactors.
SIEMENS Auxiliary Switch: 2NO/2NC, Front Mount, Front-Mounted, 3RH29112XA220MA0. Key specifications — Frame Size: S00; Brand: SIEMENS; Compatible with Series: SIRIUS 3RT2 Contactors.
Siemens
SIEMENS Auxiliary Switch: 2NO/2NC, Front Mount, Front-Mounted, 3RH29112XA220MA0. Key specifications — Frame Size: S00; Brand: SIEMENS; Compatible with Series: SIRIUS 3RT2 Contactors.
SIEMENS Auxiliary Contact: 3NO/1NC, 10 A Max Current (AC), Front Mount, Front-Mounted (MPN 3RH29111HA31). Key specifications — Frame Size: S3; Brand: SIEMENS; Compatible with Series: SIRIUS 3RT2 Contactors.
Siemens
SIEMENS Auxiliary Contact: 3NO/1NC, 10 A Max Current (AC), Front Mount, Front-Mounted (MPN 3RH29111HA31). Key specifications — Frame Size: S3; Brand: SIEMENS; Compatible with Series: SIRIUS 3RT2 Contactors.
SIEMENS Auxiliary Switch: 2NO, Front Mount, Front-Mounted (MPN 3RA6911-1A). Key specifications — Brand: SIEMENS; Compatible with Series: SIRIUS 3RA6 Compact Starters.
Siemens
SIEMENS Auxiliary Switch: 2NO, Front Mount, Front-Mounted (MPN 3RA6911-1A). Key specifications — Brand: SIEMENS; Compatible with Series: SIRIUS 3RA6 Compact Starters.

More from Siemens

View all Siemens parts
SIEMENS Mounting Flange Assembly: Mfr Part # 808-412. Key specifications — Manufacturer Part Number: 808-412; Product Type: Cap. Support Mounting Flange Assembly.
Siemens
SIEMENS Mounting Flange Assembly: Mfr Part # 808-412. Key specifications — Manufacturer Part Number: 808-412; Product Type: Cap. Support Mounting Flange Assembly.
SIEMENS Thermostat Tubing Kit: Mfr Part # 180-896. Key specifications — Manufacturer Part Number: 180-896; Product Type: Tubing Loop.
Siemens
SIEMENS Thermostat Tubing Kit: Mfr Part # 180-896. Key specifications — Manufacturer Part Number: 180-896; Product Type: Tubing Loop.
SIEMENS Switching Relay: Mfr Part # 3TX7131-4CC13. Key specifications — Manufacturer Part Number: 3TX7131-4CC13; Product Type: Switching Relay.
Siemens
SIEMENS Switching Relay: Mfr Part # 3TX7131-4CC13. Key specifications — Manufacturer Part Number: 3TX7131-4CC13; Product Type: Switching Relay.
SIEMENS Air Velocity Sensor: Mfr Part # QVM62.1-HE. Key specifications — Manufacturer Part Number: QVM62.1-HE; Product Type: Air Velocity Sensor.
Siemens
SIEMENS Air Velocity Sensor: Mfr Part # QVM62.1-HE. Key specifications — Manufacturer Part Number: QVM62.1-HE; Product Type: Air Velocity Sensor.
SIEMENS 3-Phase Busbar: Mfr Part # 3RV1915-3CB. Key specifications — Manufacturer Part Number: 3RV1915-3CB; Product Type: 3-Phase Busbar.
Siemens
SIEMENS 3-Phase Busbar: Mfr Part # 3RV1915-3CB. Key specifications — Manufacturer Part Number: 3RV1915-3CB; Product Type: 3-Phase Busbar.