# Power Supply Unit MEAN WELL MDR-40-12 40W

**URL:** https://aio.lv/en/product--mean-well-mdr-40-12--1621137
**Data updated:** 2026-01-13 17:30 (EET)
**Category:** Power Supplies (PSU)
**Manufacturer:** mean well
**Manufacturer code:** MDR-40-12
**EAN:** 4021087020916
**Warranty:** 2 Years
**Availability:** Available for order
**Price:** 31.99 €
**Prices and availability valid until:** 2026-07-20 23:59
**Price without VAT (21%):** 26.44 EUR
**Can be purchased by legal entities:** Yes (invoice)
**Buy:** https://aio.lv/en/product--mean-well-mdr-40-12--1621137

## 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 MEAN WELL MDR-40-12 is a reliable 40W power supply unit designed for various applications. It features a compact design, high efficiency, and a wide input voltage range. With short circuit, overload, and overvoltage protection, it ensures safe operation. Ideal for industrial and commercial use, this power supply is known for its durability and performance.

## Long description

The MEAN WELL MDR-40-12 40W power supply unit provides a compact, DIN-rail mountable solution for delivering stable 12V DC power in industrial and commercial installations. Designed with a broad input voltage range and efficient conversion, this unit supports continuous operation while minimizing heat generation and footprint. Built-in protections for short circuit, overload and overvoltage allow the supply to maintain safe operation under varied load conditions.
Advantages
The design combines a small form factor with reliable thermal performance and high conversion efficiency, making it suitable for space-constrained control cabinets. Integrated protection features reduce the risk of equipment damage and simplify system design by removing the need for many external protective components. The unit’s consistent output voltage and steady current delivery support stable performance of connected electronics and control devices.
Suitable for
 Industrial control cabinets and automation systems
 Building management and security systems
 LED lighting drivers and signage power
 Small to medium electrical and electronic devices requiring 12V DC
Key specifications
 Output voltage: 12 V DC
 Rated output power: 40 W
 Electrical protections: short-circuit, overload, overvoltage protection
 Mounting: DIN-rail compatible enclosure
 Input voltage range: wide AC input (suitable for standard industrial mains voltages)
 Cooling method: convection-cooled, fanless design
 Operating environment: suitable for standard industrial ambient temperatures
How to use
Install the power supply on a standard DIN-rail in a suitably ventilated control cabinet or enclosure. Connect the AC input according to local wiring practices and ensure correct grounding. Attach the 12V DC output to the load, observing correct polarity and the unit’s rated current limit. Verify output voltage with a multimeter before connecting sensitive equipment. If the unit enters protection mode due to fault conditions, disconnect the load, identify and clear the fault, and then restore power.
Usage recommendations
Locate the unit in a dry, dust-minimized environment with at least minimal clearance around the enclosure for natural convection. Avoid placing the supply near heat sources or in cramped, unventilated cabinets. For long cable runs, consider wire gauge and voltage drop to ensure reliable 12V delivery at the load. Regularly inspect connections and terminals for tightness and corrosion during maintenance intervals.

## Specifications

### Power

| Feature | Value |
|---|---|
| Total power | 40 W |

## FAQ

### How much does the Power Supply Unit MEAN WELL MDR-40-12 cost, and is it available for purchase?

The price is 31.99 € (valid at the time of publication and already includes all taxes). The item is available for order — 32 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 mean well 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 mean well 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

### How can I tell if this product suits my needs?

When making a choice, we recommend paying attention to the key features: total power, compatibility with your devices or usage conditions, material quality, functionality, and warranty terms. These characteristics will help you determine how well the model meets your needs.

## Image

https://aio.lv/img/cache/product/1621137/59841526_large.webp