# Siemens 3RH2131-2BB40 Auxiliary Contactor, 3NO + 1NC, 24V DC, Size S00

**URL:** https://aio.lv/en/product--siemens-3rh21312bb40--1841056
**Data updated:** 2026-05-18 02:47 (EEST)
**Category:** Server Parts & Components
**Manufacturer:** Siemens
**Manufacturer code:** 3RH21312BB40
**EAN:** 4011209828100
**Warranty:** 2 Years
**Availability:** Available for order
**Price:** 46.49 €
**Prices and availability valid until:** 2026-07-18 23:59
**Price without VAT (21%):** 38.42 EUR
**Can be purchased by legal entities:** Yes (invoice)
**Buy:** https://aio.lv/en/product--siemens-3rh21312bb40--1841056

## Delivery options

| Delivery method | Delivery time | Cost |
|---|---|---|
| Office pickup (2b. Kengaraga str., Riga, Latvia, LV-1063) | 13.07.2026 | free |
| Pickup points | 16.07.2026 | 1.99 EUR |
| Courier delivery to door | 16.07.2026 | 4.99 EUR |

## Summary description

The Siemens 3RH2131-2BB40 is a high-reliability auxiliary contactor designed for industrial control circuits. Featuring a size S00 design, it offers 3 normally open (NO) and 1 normally closed (NC) contacts with a 24V DC control supply voltage. This compact device is ideal for switching control signals in automation systems, ensuring efficient performance and long-term durability in demanding electrical environments.

## Long description

The Siemens 3RH2131-2BB40 is a high-reliability auxiliary contactor engineered for precise control in industrial automation systems. Built in the compact S00 size, this device is designed to handle control signals efficiently while maintaining long-term operational stability. It features a configuration of 3 normally open (NO) and 1 normally closed (NC) contacts, operating with a 24V DC control supply voltage, making it a robust solution for complex electrical switching tasks.
Advantages
This auxiliary contactor stands out due to its compact footprint, which allows for space-saving installation in crowded control cabinets. The Siemens design ensures high mechanical and electrical durability, reducing the need for frequent maintenance. Its reliable switching performance under various load conditions makes it a dependable component for critical control circuits, providing consistent connectivity and signal integrity in demanding industrial environments.
Suitable for
Industrial automation and control systems
Switching control signals in electrical panels
Integration into machine safety and monitoring circuits
General purpose auxiliary switching applications
When it may not be suitable
This device is designed specifically for auxiliary control circuits and is not intended for switching high-power main loads or motors. It is strictly limited to a 24V DC control voltage and should not be used in AC control applications or systems requiring different voltage levels.
Key specifications
Contact configuration: 3 normally open (NO) and 1 normally closed (NC)
Control supply voltage: 24V DC
Size: S00
Application: Auxiliary control circuits
How to use
The contactor should be mounted on a standard DIN rail or directly onto a mounting surface within an electrical enclosure. Ensure that the control wiring is connected to the designated terminals according to the wiring diagram. Before energizing, verify that the control voltage matches the 24V DC specification to prevent damage to the internal coil. Once installed, the device operates automatically based on the signals received from the control system.
What to consider before purchase
Verify that your control system operates on 24V DC.
Ensure the contact configuration (3NO + 1NC) meets your specific circuit requirements.
Check available space in your control cabinet to accommodate the S00 size.
Confirm compatibility with existing DIN rail mounting standards.
Usage recommendations
Always ensure that the power supply is disconnected before performing any installation or maintenance work on the control circuit to prevent electrical hazards.

## FAQ

### How much does the Siemens 3RH2131-2BB40 Auxiliary Contactor cost, and is it available for purchase?

The price is 46.49 € (valid at the time of publication and already includes all taxes). The item is available for order — 65 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 13.07.2026 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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