# Siemens 3RH1921-1EA02 Auxiliary Switch Block, 2 NC Contacts

**URL:** https://aio.lv/en/product--siemens-3rh1921-1ea02--12453236
**Data updated:** 2026-05-18 02:52 (EEST)
**Category:** Printer & Copier Parts
**Manufacturer:** Siemens
**Manufacturer code:** 3RH1921-1EA02
**EAN:** 4011209293540
**Warranty:** 2 Years
**Availability:** Available for order
**Price:** 14.99 €
**Prices and availability valid until:** 2026-07-20 23:59
**Price without VAT (21%):** 12.39 EUR
**Can be purchased by legal entities:** Yes (invoice)
**Buy:** https://aio.lv/en/product--siemens-3rh1921-1ea02--12453236

## Delivery options

| Delivery method | Delivery time | Cost |
|---|---|---|
| Office pickup (2b. Kengaraga str., Riga, Latvia, LV-1063) | 14.07.2026 | free |
| Pickup points | 17.07.2026 | 1.89 EUR |
| Courier delivery to door | 17.07.2026 | 4.99 EUR |

## Summary description

The Siemens 3RH1921-1EA02 is an auxiliary switch block featuring 2 normally closed (NC) contacts. Designed for reliable integration with contactors, this modular component provides essential feedback and control signaling in industrial automation systems. It ensures precise switching operations and is built for durability in demanding electrical environments.

## Long description

The Siemens 3RH1921-1EA02 is a high-quality auxiliary switch block designed to expand the functionality of SIRIUS 3RT1 contactors. Featuring 2 normally closed (NC) contacts, this modular component is engineered for reliable feedback and control signaling within industrial automation systems. It provides precise switching operations and is constructed to withstand the rigors of demanding electrical environments, ensuring consistent performance in control circuits.
Advantages
This auxiliary switch block offers seamless integration with 3RT1 contactors ranging from size S0 to S12. The design allows for tool-free lateral mounting, which significantly simplifies installation and maintenance processes. As part of the SIRIUS modular system, it ensures high compatibility and efficiency. The unit features positively driven contacts, which are essential for safety-critical applications, providing reliable status monitoring for power contactors.
Suitable for
Industrial automation control circuits
Status feedback for power contactors
Safety-related switching applications
Expansion of existing contactor configurations
When it may not be suitable
This specific model is designed for lateral mounting and may not be suitable for applications requiring front-mounted auxiliary switches. It is exclusively compatible with 3RT1 contactors and cannot be used with contactor series that do not support this specific modular interface.
Key specifications
Contact configuration: 2 normally closed (NC) contacts
Mounting type: Lateral
Terminal type: Screw terminal
Compatibility: SIRIUS 3RT1 contactors (sizes S0 to S12)
Function: Instantaneous switching
How to use
The auxiliary switch block is designed for quick and easy installation. It can be attached to the side of a compatible 3RT1 contactor without the need for specialized tools. Once snapped into place, the screw terminals allow for secure connection of control wiring. Ensure the power is disconnected before installation and verify that the contactor size is within the supported S0 to S12 range to ensure proper mechanical and electrical alignment.
What to consider before purchase
Verify the mounting orientation requirements of your current control panel layout.
Confirm that your contactor model is part of the 3RT1 series.
Ensure that the 2 NC contact configuration meets your specific control logic requirements.
Check if your wiring setup is compatible with screw-type terminals.
Usage recommendations
Always ensure that the auxiliary switch is fully engaged with the contactor housing before applying power. Regularly inspect the screw terminal connections to maintain optimal electrical contact and prevent signal loss in the control circuit.

## FAQ

### How much does the Siemens 3RH1921-1EA02 Auxiliary Switch Block cost, and is it available for purchase?

The price is 14.99 € (valid at the time of publication and already includes all taxes). The item is available for order — 1 pcs. are in stock, and you can place your purchase right now with delivery across Latvia and Europe or choose pickup at the Riga collection point. We offer favorable purchase terms, including the option to split the payment into convenient monthly installments. Availability and price are updated in real time, so we recommend placing your order in advance.

### If I order this product today, when will I receive my order?

If you place your order today, delivery will be as fast and convenient as possible. You will be able to pick up your order on 14.07.2026 at the Riga pickup point or choose delivery across Latvia and Europe. We carefully inspect every purchase and pack it securely for safe transportation.

### What payment options are available?

AiO.lv offers several payment methods: Bank transfer, Bank cards on-line, Apple Pay, Google Pay. All transactions are 100% secure and encrypted.

### Can this product be purchased for a company (with VAT)?

Yes. AiO.lv works with legal entities in Latvia and across Europe. The product price already includes VAT. For certain product categories, as well as for companies from other EU countries with a valid VAT number, a 0% VAT rate may apply. We issue the invoice immediately after the order is placed, support electronic BIS invoices, and automatically generate all necessary accounting documents. You can complete the purchase for a company online — simply select the company profile and choose bank transfer as the payment method during checkout.

### What is the warranty period?

All Siemens products come with an official 2 Years warranty. It covers all manufacturing defects and malfunctions that may occur during use. The warranty is valid at all authorized Siemens service centers and through AiO.lv

### Can the product be returned after purchase?

Yes, you can return the product within 14 days of purchase if you bought it as a consumer (not a legal entity). Returns are possible without giving any reason — the main condition is that the product retains its original appearance and full set of accessories. We will make the process as simple and convenient as possible: just contact our customer support team, and we will help you arrange the return.

### Where should I contact for warranty service?

For warranty-related questions you can contact the AiO.lv (SIA VSPRO) customer support team. More information about warranty service: https://aio.lv/en/warranty

## Image

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