Door state detection circuit diagram

inductance

The image above illustrates a bus door state detection circuit, which relies on three Hall effect sensors to monitor the status of the door in various types of vehicles. These sensors are mounted on the door frame, while magnets are positioned on the door itself. When the door is open, the magnet moves away from the sensor, causing it to output a high voltage signal. If any one of the three Hall sensors detects that the door is not fully closed or locked, the NOR gate will trigger a low-level signal, which activates the red indicator light. This serves as a clear warning that the door is not properly secured. On the other hand, when all three sensors detect that the door is closed and locked, they each send a high-level signal. This causes the NAND gate to produce a high-level output, turning on the green indicator light. This system provides real-time feedback on the door’s status, ensuring safety and reliability in public transportation systems. It's an efficient and cost-effective solution for monitoring door positions, especially in large vehicles where security and operational efficiency are crucial.