The **T40-DISCO-ROCIADOR-INFER** (Lower Spray Disc for the DJI Agras T40) is a critical component of the aircraft's centrifugal atomization system. Unlike traditional pressure nozzles, this electronic assembly uses high-speed rotation to break down liquid into droplets. ### 1. Core Electronic Components The assembly consists of several integrated parts that work together to manage fluid dynamics and motor control: | Component | Function | Description | | :--- | :--- | :--- | | **Brushless DC Motor (BLDC)** | Propulsion | A high-torque, high-speed motor that spins the disc at rates up to 14,000 RPM. | | **Internal ESC (Electronic Speed Controller)** | Power Logic | Regulates the voltage and current to the motor to maintain precise RPM based on flight controller commands. | | **Hall Effect Sensor** | Feedback | Monitors the actual rotation speed (RPM) to ensure consistent droplet size and detect clogs or motor failure. | | **Communication Interface** | Data Link | Connects via a specialized wiring harness to the main spray controller to receive "Start/Stop" and "RPM set" signals. | --- ### 2. Technical Specifications & Operating Principles The electronic performance of the lower spray disc is defined by its ability to convert electrical energy into mechanical centrifugal force: * **Atomization Principle:** The motor spins the **Atomizing Disc** (the physical plastic/composite plate). Liquid is fed onto the center; centrifugal force pushes the liquid through the teeth of the disc, shearing it into uniform droplets. * **Variable Droplet Control:** By electronically adjusting the motor frequency (RPM), the pilot can change the droplet size (VMD - Volume Median Diameter) directly from the DJI RC Plus remote. * **Sealing and Protection:** Because it sits directly under the spray tank, the electronics are housed in an **IP67-rated enclosure** to prevent pesticide corrosion and water ingress during cleaning. --- ### 3. Wiring and Connection Layout The assembly typically connects to the T40 arm's internal wiring via a quick-release or secure circular connector: ```yaml Pinout_Logic: - Power_V+: High-voltage DC input from the flight battery. - Power_GND: Common ground. - Signal_PWM/CAN: Controls the speed of rotation. - Feedback_Line: Sends RPM data back to the DJI Agras flight system for real-time monitoring. ``` --- ### 4. Maintenance and Troubleshooting | Issue | Electronic Cause | Solution | | :--- | :--- | :--- | | **Uneven Spray** | Motor RPM fluctuation | Check for debris around the motor shaft or recalibrate the spray system. | | **Disc Not Spinning** | ESC Failure / Connection Error | Inspect the wiring harness for corrosion; ensure the 8-pin/multi-pin connector is dry. | | **Overload Warning** | Bearing Resistance | The motor is drawing too much current (Amps). Replace the disc assembly or check for physical blockages. | ---