## Technical Overview: Delta EFB0412HA-R00 The **EFB0412HA-R00** is a high-performance, compact axial cooling fan manufactured by **Delta Electronics**. It is part of the "EFB" series, known for utilizing ball bearings and high-efficiency blade designs. --- ### 1. Key Technical Specifications | Feature | Specification | | :--- | :--- | | **Frame Size** | 40mm x 40mm x 10mm | | **Rated Voltage** | 12V DC | | **Operating Voltage Range** | 7.0V to 13.8V | | **Rated Current** | 0.10A (Max 0.15A) | | **Rated Power** | 1.20W | | **Speed** | 6000 RPM | | **Max Airflow** | 6.92 CFM (0.196 m³/min) | | **Static Pressure** | 4.22 mmH₂O | | **Noise Level** | 28.5 dB-A | | **Bearing Type** | Dual Ball Bearing | --- ### 2. Electronic Interface & Signal Details The suffix **-R00** is a specific Delta designation for the output signal provided by the fan's third wire. * **Wiring Configuration:** * **Red:** Positive (+12V) * **Black:** Negative (GND) * **Blue/White:** **R00 Sensor (Lock Sensor)**. * **The R00 Function:** Unlike the "F00" (Tachometer/Speed sensor), the **R00** is a **Rotation Detector**. * Under normal operation (fan spinning), the signal output is **Low**. * If the fan stops (locked rotor), the signal output switches to **High**. * This is primarily used as a "Fail-Safe" alarm for system controllers to detect hardware failure. --- ### 3. Internal Component Construction * **Motor Type:** Brushless DC (BLDC) motor. * **Commutation:** Electronic commutation provided by an internal Integrated Circuit (IC). * **Protection Features:** 1. **Locked Rotor Protection:** The IC prevents the coils from burning out if the blades are physically obstructed. 2. **Polarity Protection:** Protects the internal circuitry if the positive and negative leads are accidentally reversed. * **Materials:** * **Impeller/Frame:** Plastic (UL 94V-0 rated), typically glass-fiber reinforced PBT. --- ### 4. Comparison of Signal Types | Signal Suffix | Type | Description | | :--- | :--- | :--- | | **-F00** | Tachometer | Output pulses proportional to RPM (Speed monitoring). | | **-R00** | Lock Sensor | Binary signal (High/Low) based on rotation status (Failure monitoring). | | **Standard** | 2-Wire | No feedback signal; power and ground only. |