The **FUD-20-R/Q** is a high-precision, fiber-optic amplifier (sensor) primarily used in industrial automation for object detection and position sensing. The "R" usually denotes a Red LED light source, and the "Q" indicates a specific connector type or response speed variant. --- ## 1. Core Electronic Specifications The electronic architecture of the FUD-20-R/Q is designed for high-speed switching and reliability in harsh industrial environments. | Feature | Specification | | :--- | :--- | | **Power Supply** | 12 to 24V DC (±10% ripple) | | **Current Consumption** | Max 40mA | | **Light Source** | Red LED (Visible) | | **Response Time** | High Speed: ~50µs / Standard: ~250µs | | **Output Type** | NPN or PNP Open Collector (model dependent) | | **Sensitivity Adjustment** | 8-turn potentiometer or Digital Teach-in | --- ## 2. Key Electronic Components ### A. The Optical Transceiver * **Emitter (LED):** A high-intensity red LED pulses light through the fiber optic cable. The pulsing allows the sensor to distinguish its own signal from ambient light interference. * **Receiver (Photodiode):** A high-speed silicon photodiode detects reflected light. It converts optical energy into a low-level electrical current. ### B. Signal Processing Circuitry * **Amplifier Stage:** The weak signal from the photodiode is boosted. The "Gain" is controlled via the sensitivity adjustment to filter out background noise. * **Comparator:** This circuit compares the received signal level against a pre-set threshold. If the signal exceeds the threshold, the output state changes. * **Timing Logic:** Includes delay timers (ON-delay, OFF-delay, or One-shot) to stabilize the output signal for PLCs. ### C. Output Protection The electronic output stage is typically protected against: 1. **Reverse Polarity:** Prevents damage if the + and - wires are swapped. 2. **Short Circuit:** Limits current if the output load is shorted. --- ## 3. Wiring Configuration The device generally follows the standard industrial color code for a 3-wire or 4-wire DC sensor: ```yaml Brown: +V (12-24V DC) Blue: 0V (GND) Black: Control Output (Load) White: Mode Selection (Light-ON / Dark-ON) ``` --- ## 4. Operational Modes * **Light-ON (L-ON):** The output is energized when the receiver detects light. * **Dark-ON (D-ON):** The output is energized when the light path is broken (object present).