Smart School Bell & Siren Hardware Integration

The YeneSchool Smart Siren Module automates your physical school bell, eliminating the need for manual guard intervention. The system synchronizes directly with the active academic timetable, triggering electric gongs, PA audio chimes, or electronic sirens punctually at period breaks, lunch intervals, and morning assemblies.

1. Hardware Bill of Materials (BOM)

To build a low-cost, industrial-grade automated bell controller:

• Microcontroller: ESP32 DevKit v1 or ESP8266 Wi-Fi board (~$5 - $8 USD).
• Relay Module: 1-Channel 5V Optocoupler Relay Module rated for 10A / 250V AC.
• Power Supply: 5V 2A micro-USB power adapter.
• Bell Device: Standard existing school electric bell (220V AC solenoid gong or 12V DC electronic siren).
• Enclosure: IP65 plastic junction box for wall mounting.

2. Microcontroller Firmware & Webhook Configuration

The ESP32 runs a lightweight HTTP server listening on the school's local LAN (or connected via a secure reverse tunnel):

// ESP32 Arduino Sketch Snippet
#include <WiFi.h>
#include <WebServer.h>

const int RELAY_PIN = 23;
WebServer server(80);

void handleTrigger() {
  int duration = 4000; // default 4 seconds
  if (server.hasArg("durationMs")) {
    duration = server.arg("durationMs").toInt();
  }
  
  digitalWrite(RELAY_PIN, HIGH); // Close relay
  delay(duration);
  digitalWrite(RELAY_PIN, LOW);  // Open relay
  
  server.send(200, "application/json", "{\"status\":\"RING_COMPLETE\"}");
}

void setup() {
  pinMode(RELAY_PIN, OUTPUT);
  digitalWrite(RELAY_PIN, LOW);
  WiFi.begin("School_Staff_WiFi", "SecureWifiPassword123");
  // ... Wait for connection ...
  server.on("/api/bell/ring", HTTP_POST, handleTrigger);
  server.begin();
}

3. Configuring the Siren in YeneSchool

1. Navigate to Director Portal > Platform Settings > Siren Settings (/director/siren).
2. Enter the Hardware Webhook URL: http://192.168.1.150/api/bell/ring (or custom HTTPS cloud webhook URL).
3. Set the Auth Shared Secret: Token validated by the controller to prevent unauthorized rings.
4. Define Bell Pulse Durations:
   • Period Change: 4 Seconds (Single Pulse).
   • Morning Assembly: 8 Seconds (Double Pulse).
   • Recess / Lunch: 5 Seconds (Triple Pulse).
   • Emergency / Evacuation: Continuous 30-Second Alarm.
5. Click Test Hardware Ring: The platform immediately sends a test pulse to confirm physical bell operation.