The **M2PRU-A27R-R2/UL** is a high-performance, industrial-grade AC/DC switching power supply module, often utilized in redundant power configurations for servers, networking equipment, and storage systems. Below is a detailed breakdown of its electronic specifications and technical features. --- ### 1. General Specifications This unit is typically categorized as a **1U Redundant Power Supply Unit (PSU)**. | Feature | Specification | | :--- | :--- | | **Manufacturer** | Etasis (Common OEM) | | **Form Factor** | 1U Proprietary / Module | | **Maximum Power Output** | 275W - 300W (Model dependent variant) | | **Input Voltage Range** | 100V - 240V AC (Auto-ranging) | | **Efficiency Rating** | 80 PLUS Silver/Gold (Depending on revision) | | **Certification** | UL, TUV, CE, CB | ### 2. Output Rail Characteristics The power is distributed across several DC rails to support logic boards and peripheral hardware. | Rail | Max Current (Approx.) | Function | | :--- | :--- | :--- | | **+3.3V** | 15A - 20A | Logic circuits, memory | | **+5V** | 15A - 20A | Storage drives, USB, Logic | | **+12V** | 18A - 22A | CPU, GPU, Cooling Fans | | **-12V** | 0.5A | Legacy serial ports | | **+5Vsb** | 2.0A - 3.0A | Standby power (Always on) | ### 3. Key Electronic Features * **PFC (Power Factor Correction):** Includes Active PFC to ensure high energy efficiency and reduced harmonic distortion on the power grid. * **Redundancy Support:** Equipped with an internal "Oring" Diode or MOSFET circuit, allowing it to work in parallel with a second module (N+1 redundancy) without back-feeding power. * **Protection Circuits:** * **OVP (Over Voltage Protection):** Shuts down the unit if voltage exceeds safe limits. * **OCP (Over Current Protection):** Prevents damage from excessive current draw. * **SCP (Short Circuit Protection):** Immediate shutoff in case of a short. * **OTP (Over Temperature Protection):** Monitors internal heatsinks via thermistors. * **Cooling:** Internal 40mm high-speed ball-bearing fan with PWM speed control based on load and temperature. ### 4. Interface and Connection The "R2/UL" suffix usually denotes a specific connector type and safety certification. * **Connector Type:** Typically uses a gold-finger edge connector (PCB-based) rather than standard ATX cables. This slides into a power distribution board (PDB). * **Communication:** Supports **PMBus** or **I2C** protocols for digital monitoring of fan speed, temperature, and power consumption by the system BIOS/BMC. ---