The part number **48AV-4YHA-R** refers to a specific type of **high-performance DC Axial Fan**, typically manufactured by companies like **Nidec (formerly UltraFlo/Servo)**. These fans are commonly used in enterprise-level networking equipment, servers, and industrial cooling applications. --- ### 1. Technical Specifications Below is a breakdown of the typical electronic and mechanical characteristics for this series: | Parameter | Specification (Typical) | | :--- | :--- | | **Rated Voltage** | 48V DC | | **Operating Voltage Range** | 36V to 72V DC | | **Dimensions** | 40mm x 40mm x 28mm (Commonly 4028 size) | | **Bearing Type** | Dual Ball Bearing (for long life) | | **Termination** | 4-Wire (Power, Ground, Tachometer, PWM) | | **Housing Material** | UL 94V-0 Plastic or Aluminum | --- ### 2. Key Electronic Components & Features #### A. Brushless DC (BLDC) Motor At the core of the part is a BLDC motor. Unlike brushed motors, these use an electronic controller to switch the current to the motor windings, which reduces friction, noise, and electromagnetic interference (EMI). #### B. The 4-Wire Interface This fan uses a standard 4-wire control scheme, which is critical for modern server management: 1. **Red (+):** Power supply (48V). 2. **Black (-):** Ground. 3. **Yellow/White (Tachometer):** Outputs a frequency signal proportional to the fan speed (RPM) for system monitoring. 4. **Blue/Green (PWM Control):** Allows the system to vary the fan speed based on cooling demand, significantly reducing power consumption. #### C. Integrated Protection Circuits * **Auto-Restart:** If the blades are obstructed, the internal IC shuts down power to the coils to prevent overheating and attempts to restart once the obstruction is cleared. * **Reverse Polarity Protection:** Prevents damage if the power leads are connected incorrectly. --- ### 3. Application Use Cases Due to its **48V** rating (higher than the standard 12V found in PCs), this part is specifically engineered for: * **Telecommunications:** Cooling for base stations and routers. * **Data Centers:** High-density server racks where 48V power distribution is standard. * **Industrial Automation:** Power supplies and motor drives. ---