NVVV MDR-20-12 AC to DC DIN-Rail Power Supply 12V 1.67 Amp 20W vs MEIRIYFA Desktop Computer Power Switch Power Supply Cable

Design and Form Factor

The NVVV MDR-20-12 and the MEIRIYFA Desktop Computer Power Switch serve fundamentally different design purposes, reflected clearly in their form factors. The NVVV MDR-20-12 is a DIN-rail power supply module designed for mounting inside industrial or electrical cabinets, whereas the MEIRIYFA is a small, external desktop power switch with a cable designed for user convenience.

NVVV MDR-20-12 measures as a 20W power supply unit suited for fixed installations with a standard DIN-rail mount, making it ideal for industrial or automation setups. In contrast, the MEIRIYFA power switch is a portable, lightweight device measuring 6.5cm by 3cm and weighing just 30 grams, designed to be placed on a desk or adhered to surfaces with double-sided tape. This makes MEIRIYFA far more suitable for end-user accessibility in home or office environments, while NVVV caters to fixed power supply needs.

Functionality and Use Case

The two products differ drastically in their core functions. NVVV MDR-20-12 converts AC to DC power, providing a stable 12V output at 1.67 amps, with a maximum power output of 20 watts. This makes it essential for powering low-voltage devices and systems requiring regulated DC power from an AC source.

On the other hand, the MEIRIYFA product is not a power supply but a desktop computer power switch with a 2-meter cable, designed to remotely control the power state of a PC. It extends the physical power button’s reach, allowing users to turn their computer on or off from a convenient location. It also incorporates a mechanical keyboard switch for quick, tactile feedback and supports standard motherboard connectors for power and LED signals, enabling full startup and restart functions externally.

Electrical Specifications

When it comes to electrical capabilities, NVVV MDR-20-12 provides a defined output voltage of 12V DC and an output current of 1.67 amps. Its input voltage range is wide, from 85 to 264 VAC, making it compatible with various power sources. These specs make it suitable for powering small devices or circuits needing steady DC power up to 20 watts.

The MEIRIYFA switch does not handle voltage conversion or power supply duties but acts as a control interface for the computer’s power function. It relies on motherboard power signals (POWER LED+, POWER LED-, POWER SW, RESET SW, HDD LED+) and has no inherent power output or input ratings. This means MEIRIYFA functions purely as a signal switch rather than a source of power.

Installation and Compatibility

Installation processes differ significantly. The NVVV MDR-20-12 requires mounting on a DIN rail, typically within an electrical cabinet or industrial panel, and wiring to the AC input and DC output terminals. This installation is fixed and suited for permanent setups.

Conversely, MEIRIYFA is designed for easy installation on desktop PCs. The package includes instructions for connecting the switch to motherboard headers, and it features a 2-meter cable to reach from the PC chassis to a convenient desktop location. It comes with adhesive pads and cable ties for secure placement and cable management, making it very user-friendly for end consumers and DIY PC builders.

Durability and Build Quality

MEIRIYFA emphasises user experience with a mechanical keyboard-style switch rated for up to 5 million keystrokes, ensuring long-lasting tactile feedback and durability for repeated use. Its compact ABS plastic casing protects the switch, while its lightweight build makes it portable.

NVVV MDR-20-12’s build quality is implied by its industrial-grade DIN-rail design, engineered to operate reliably under a wide input voltage range (85 to 264 VAC) and continuous load up to 20W. Such power supplies typically feature protections against overvoltage, overcurrent, and thermal stress, though these specifics are not detailed here. The robust design ensures steady output for sensitive equipment.

Price Comparison

Both products are competitively priced within a similar range, with MEIRIYFA slightly cheaper at C$21.14 compared to NVVV MDR-20-12’s C$21.41. The price difference of just C$0.27 is negligible, so cost should not be the decisive factor when choosing between these products. Instead, the choice should be dictated by the intended application—power conversion or power switch functionality.

User Experience and Convenience

MEIRIYFA excels in user convenience by offering an external power switch that can be placed anywhere on the desk, eliminating the need to reach behind or bend down to power on the computer. The mechanical switch provides satisfying tactile feedback, and its 2-meter cable length offers flexibility for positioning.

NVVV MDR-20-12, being a fixed power supply, does not provide user interaction or convenience features but focuses on delivering reliable power. It is ideal for users who need a stable 12V DC source but do not require remote control or accessibility features.

Which should you buy?

Choose NVVV MDR-20-12 if you need a reliable 12V DC power supply capable of outputting up to 1.67 amps and 20 watts, especially for industrial or embedded applications requiring DIN-rail mounting and regulated power conversion. Its broad input voltage range and fixed installation suit professional setups.

Opt for MEIRIYFA if your primary need is to conveniently control the power state of a desktop computer from a distance using an external mechanical power switch. It is perfect for home or office PC users who want easy access to their computer’s power button without reaching behind the chassis. The switch’s durability and included accessories make it a practical replacement or upgrade for existing PC power controls.

In summary, these products serve very different functions at similar price points, so your choice depends entirely on whether you need a power supply or an accessible power switch for your desktop computer.