The **W2AC-AC4B-R2** is a specific part number belonging to a series of industrial cooling fans, typically manufactured by **Sanyo Denki** (San Ace line). This particular model is an AC-powered axial fan designed for high-reliability cooling in server racks, power supplies, and industrial control panels. --- ### 1. Technical Specifications Table The electronic and physical characteristics of the W2AC-AC4B-R2 are summarized below: | Feature | Specification | | :--- | :--- | | **Input Voltage** | 200V / 230V AC (Dual Frequency) | | **Frequency** | 50 / 60 Hz | | **Frame Size** | 120mm x 120mm x 38mm | | **Bearing Type** | Dual Ball Bearing | | **Termination** | Lead Wire or Terminal type (depending on sub-variant) | | **Frame Material** | Aluminum Die-cast | | **Impeller Material** | Plastic (UL 94V-0) | | **Expected Life** | Approx. 40,000 to 100,000 Hours (at 40°C) | --- ### 2. Key Electronic Components & Features #### A. The Induction Motor The heart of this part is a **single-phase AC induction motor**. Unlike DC fans that require a controller board (PCB) to commutate the motor, AC fans utilize the oscillating nature of the input current to create a rotating magnetic field. * **Capacitor-Run:** High-efficiency AC fans often include an internal capacitor to shift the phase and provide starting torque. * **Burnout Protection:** Most models in this series include **Impedance Protection**. This ensures that if the blades are locked, the internal resistance of the coils prevents the temperature from rising to a point that would cause a fire. #### B. Bearings and Friction Control The "R2" designation often refers to a specific revision or bearing optimization. * **Dual Ball Bearings:** These are used to handle the heat generated by the motor coils and allow the fan to be mounted in any orientation (horizontal, vertical, or angled) without degrading the lifespan. #### C. EMI/RFI Considerations Because it runs on high-voltage AC, it produces very low Electromagnetic Interference (EMI) compared to PWM-controlled DC fans, making it ideal for sensitive analog equipment environments. --- ### 3. Wiring Diagram (Logic) The wiring is straightforward compared to DC fans. There is no "Sense" or "Control" wire unless specifically ordered with a sensor option. ```text [Power Source L] -------- (Brown/Black Wire) -------- [ Fan Motor ] [Power Source N] -------- (Blue/White Wire) -------- [ Fan Motor ] [Ground/Earth ] -------- (Green/Yellow) -------- [ Chassis/Frame ] ``` --- ### 4. Application Areas * **Industrial Cabinets:** Heat dissipation for PLCs and Motor Drives. * **Telecommunications:** Cooling for base stations and network switches. * **Medical Equipment:** High-reliability cooling for imaging systems.