# Siemens 3RH2921-1DA11 Auxiliary Switch Block, 1NO + 1NC, Side-Mounted, Size S0

**URL:** https://aio.lv/en/product--siemens-3rh29211da11--1840582
**Data updated:** 2026-05-18 02:47 (EEST)
**Category:** Computer Component Accessories
**Manufacturer:** Siemens
**Manufacturer code:** 3RH29211DA11
**EAN:** 4011209790285
**Warranty:** 2 Years
**Availability:** Available for order
**Price:** 39.49 €
**Prices and availability valid until:** 2026-07-27 23:59
**Price without VAT (21%):** 32.64 EUR
**Can be purchased by legal entities:** Yes (invoice)
**Buy:** https://aio.lv/en/product--siemens-3rh29211da11--1840582

## Delivery options

| Delivery method | Delivery time | Cost |
|---|---|---|
| Office pickup (2b. Kengaraga str., Riga, Latvia, LV-1063) | 16.07.2026 | free |
| Pickup points | 21.07.2026 | 1.89 EUR |
| Courier delivery to door | 21.07.2026 | 15.50 EUR |

## Summary description

The Siemens 3RH2921-1DA11 is a side-mounted auxiliary switch block designed for size S0 contactors. It features one normally open (NO) and one normally closed (NC) contact configuration. This modular component is essential for expanding the switching capabilities of industrial control systems, ensuring reliable signal feedback and integration within electrical automation setups.

## Long description

The Siemens 3RH2921-1DA11 auxiliary switch block is a high-quality modular component engineered for seamless integration with size S0 contactors. This side-mounted device provides essential feedback and control signaling by offering one normally open (NO) and one normally closed (NC) contact. Designed for industrial automation, it ensures reliable performance and expands the functional capacity of your electrical control systems.
Advantages
This auxiliary switch block offers a robust design that guarantees long-term operational reliability in demanding industrial environments. Its side-mounted configuration allows for space-efficient installation, making it an ideal choice for compact control panels where every millimeter counts. The inclusion of both NO and NC contacts provides versatile switching options, allowing for flexible circuit design and comprehensive monitoring of contactor status.
Suitable for
Industrial automation and control systems
Signal feedback for PLC inputs
Interlocking circuits in motor starters
Status monitoring of electrical equipment
When it may not be suitable
This component is specifically designed for size S0 contactors and may not be compatible with other contactor sizes or different brands. It is intended for industrial control applications and is not suitable for residential household wiring or high-voltage power distribution systems.
Key specifications
Contact configuration: 1 NO + 1 NC
Mounting type: Side-mounted
Compatibility: Size S0 contactors
Function: Auxiliary switching
How to use
To install the auxiliary switch block, ensure the main power supply to the contactor is disconnected. Align the switch block with the designated side mounting interface on the S0 contactor and snap it into place until it is securely locked. Once attached, connect the control wiring to the terminal points according to your circuit diagram. Verify that the mechanical linkage is correctly engaged before restoring power to the system.
What to consider before purchase
Verify that your contactor is size S0
Ensure the contact configuration (1NO + 1NC) meets your control logic requirements
Check available space on the side of your contactor for mounting
Usage recommendations
Always perform a functional test of the auxiliary contacts after installation to ensure the signal feedback corresponds correctly to the contactor state. Ensure all terminal connections are tightened to the manufacturer's specified torque to prevent loose contacts and potential signal errors.

## FAQ

### How much does the Siemens 3RH2921-1DA11 Auxiliary Switch Block cost, and is it available for purchase?

The price is 39.49 € (valid at the time of publication and already includes all taxes). The item is available for order — 13 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 16.07.2026 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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