# Siemens 3RF2120-1AA02 1-Phase Solid State Relay, 20 A, 24-230 V AC / 24 V DC

**URL:** https://aio.lv/en/product--siemens-3rf2120-1aa02--1795925
**Data updated:** 2026-05-18 02:39 (EEST)
**Category:** Control Systems
**Manufacturer:** Siemens
**Manufacturer code:** 3RF2120-1AA02
**EAN:** 4011209573772
**Warranty:** 2 Years
**Availability:** Available for order
**Price:** 47.99 €
**Prices and availability valid until:** 2026-07-18 23:59
**Price without VAT (21%):** 39.66 EUR
**Can be purchased by legal entities:** Yes (invoice)
**Buy:** https://aio.lv/en/product--siemens-3rf2120-1aa02--1795925

## 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 3RF2120-1AA02 is a high-performance 1-phase solid state relay designed for reliable switching in industrial applications. It features a rated load current of 20 A and operates with a control voltage of 24 V DC and a load voltage range of 24-230 V AC. This compact semiconductor relay ensures silent, wear-free switching, making it an ideal solution for heating systems, motor control, and various automation tasks requiring frequent switching cycles.

## Long description

The Siemens 3RF2120-1AA02 is a high-performance 1-phase solid state relay engineered for precise and reliable switching in demanding industrial environments. This semiconductor relay is designed to handle a rated load current of 20 A, providing a robust solution for managing electrical loads with a voltage range between 24 V and 230 V AC. By utilizing advanced solid-state technology, it offers a durable alternative to traditional electromechanical contactors, ensuring consistent performance even in applications that require high-frequency switching cycles.
Advantages
The primary benefit of this solid state relay is its ability to perform silent and wear-free switching, which significantly extends the operational lifespan of the device compared to mechanical relays. Because it lacks moving parts, it is immune to contact bounce and mechanical fatigue, making it highly reliable for continuous industrial use. Its compact design allows for efficient space utilization within control cabinets, while the integrated control circuitry ensures rapid response times and seamless integration into existing automation systems.
Suitable for
Heating systems and temperature control applications
Motor control and soft starting operations
Industrial automation and process control systems
Lighting control and power distribution tasks
When it may not be suitable
This relay is not designed for switching high-voltage DC loads, as it is specifically optimized for AC load switching. Additionally, it may not be suitable for environments where extreme heat dissipation cannot be managed, as solid state relays generate heat during operation and may require additional cooling or proper mounting to prevent thermal overload.
Key specifications
Rated load current: 20 A
Load voltage range: 24-230 V AC
Control voltage: 24 V DC
Switching type: 1-phase solid state
Design: Compact semiconductor relay
How to use
Installation should be performed by qualified personnel in accordance with local electrical regulations. The relay is typically mounted on a standard DIN rail or a flat surface depending on the specific configuration. Connect the 24 V DC control signal to the designated input terminals and wire the AC load circuit to the output terminals. Ensure that the load current does not exceed the rated 20 A capacity and that adequate ventilation is provided around the unit to maintain optimal operating temperatures.
What to consider before purchase
Verify that your control signal matches the 24 V DC requirement
Ensure the load current does not exceed 20 A
Check that your load voltage falls within the 24-230 V AC range
Assess the need for a heat sink based on your specific load and ambient temperature
Usage recommendations
For optimal longevity and performance, ensure the relay is mounted in a vertical position to facilitate natural convection cooling. If the device is used in high-frequency switching applications, monitor the ambient temperature closely and consider forced air cooling if the operating environment exceeds standard industrial limits.

## FAQ

### How much does the Siemens 3RF2120-1AA02 Solid State Relay cost, and is it available for purchase?

The price is 47.99 € (valid at the time of publication and already includes all taxes). The item is available for order — 5 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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