Explanation of Mobile Toilet Circuit Diagram

The mobile toilet circuit diagram mainly involves two parts: the power supply architecture and the automatic flushing controller circuit. Here is a detailed explanation:

Power Supply Architecture

The power supply for mobile public toilets starts with connecting to a 220V power source. Through an AC-DC module, alternating current is converted into direct current, with common conversion voltages being 12V or 24V. The converted direct current supplies power to various devices, including presence/absence indicator signs, ceiling-mounted speakers, exhaust fans, toilet stall human body sensors, lighting fixtures, and smart locks for partition doors. These devices are connected to the controller via IO signals, enabling centralized control and management. This power supply architecture is reasonably designed, meeting the power requirements of multiple devices within the mobile toilet. Moreover, through centralized control, it facilitates the operation and monitoring of each device, enhancing the convenience of use and management efficiency of the mobile toilet.

Automatic Flushing Controller Circuit

• Power Supply Circuit: A 12V power supply circuit is composed of transformer T, VD1-VD4, VD5, and C1, providing a stable power source for the entire automatic flushing control system. A stable power supply is the foundation for the normal operation of the circuit, ensuring that each component can function as designed.
• Control Core: The NE555 timer circuit serves as the control core. It forms a pulse signal oscillator with an automatically adjustable duty cycle together with surrounding components. The NE555 timer circuit has multiple functions, capable of generating corresponding output signals based on different input signals, thereby controlling the solenoid valve.
• Flushing Principle: When the power is turned on, C2 charges through R1 and VD6. Pin 2 of IC is at a low level, and pin 3 is at a high level. The solenoid valve is energized and starts to release water. The charging time of C2 is 10s, so the water release time is also approximately 10s. After C2 is fully charged, pin 3 becomes low, and VS is cut off. Subsequently, C2 discharges through VD7, R3, R2, and the internal discharge tube of IC. During the day with light, the resistance of R2 is 5kΩ, and the discharge time of C2 is 15min. At night without light, R2 is 5MΩ, and the discharge time of C2 is 1h. After discharge is complete, pin 3 of IC becomes high again, VS is turned on, and YA is energized to release water. This cycle repeats, achieving the goal of flushing the toilet once every 15min during the day and once every 1h at night for water conservation. In the diagram, S is a manual control switch that can be used to manually control water release for flushing.