Sump Controller

An basic IoT project to monitor and control the water level in a collecting sump using ESP8266 NodeMCU with email notifications and visual/audio alerts.

Overview

This project implements a smart water level monitoring system for sump pumps or water collection basins. The system uses two float switches to detect water levels and provides real-time notifications via email, visual LED indicators, and an audible alarm. The ESP8266 NodeMCU connects to WiFi to send status updates to multiple recipients.

Features

• Dual Water Level Detection: Uses two float switches (low and high) to monitor water levels
• Email Notifications: Sends automatic email alerts via Gmail SMTP for different water level conditions:
  • Critical: High water level reached
  • Warning: Low water level reached
  • Restoring: High float deactivated but low float still submerged
  • OK: System returned to normal
  • Weekly checkup: Automatic status email every week
• Visual Indicators: RGB LED provides color-coded status:
  • 🟢 Green: Normal operation
  • 🔵 Blue: Warning state
  • 🔴 Red: Critical state
• Audio Alert: Buzzer alarm for abnormal water levels with manual disable option
• Alarm Control: Additional button to temporarily disable/enable the audio alarm
• Watchdog Protection: Prevents ESP8266 crashes during operation

Hardware Requirements

• ESP8266 NodeMCU development board
• 2x Float switches (low and high water level)
• RGB LED module (common cathode)
• Passive buzzer
• Push button (for alarm control)
• Connecting wires
• Power supply (5V USB or appropriate power source)

Pin Configuration

Component	GPIO Pin	NodeMCU Pin
Low Float Switch	GPIO 12	D6
High Float Switch	GPIO 13	D7
Buzzer	GPIO 14	D5
Red LED	GPIO 5	D1
Blue LED	GPIO 4	D2
Green LED	GPIO 16	D0
Additional Button	GPIO 10	SD3

Circuit Diagram

The Fritzing schematic is available in the fritzing/ folder. Additional custom modules used in the design:

• ESP8266 NodeMCU module
• Passive Buzzer module
• RGB Full Color LED module

Software Dependencies

Arduino Libraries Required

1. ESP8266WiFi - WiFi connectivity for ESP8266
2. ESP_Mail_Client - For sending emails via SMTP
3. aplayer - Arduino Buzzer Player library from https://github.com/prittt/ArduinoBuzzerPlayer

Installation

Install the required libraries through the Arduino IDE Library Manager or manually download them from their respective repositories.

Configuration

1. Arduino IDE Setup for ESP8266

Follow the instructions here to enable programming of ESP8266 NodeMCU with Arduino IDE: Setting Up the Arduino IDE to Program ESP8266

2. WiFi Configuration

Edit the following lines in code/code.ino:

#define WIFI_SSID "your_wifi_ssid"
#define WIFI_PASSWORD "your_wifi_password"

3. Email Configuration

Configure your Gmail account for SMTP:

#define AUTHOR_EMAIL "your_email@gmail.com"
#define AUTHOR_PASSWORD "your_app_password"

Important: Use an App Password instead of your regular Gmail password for security.

Add recipient emails and names:

String emails[] = {"recipient1@example.com", "recipient2@example.com"};
size_t emails_size = sizeof(emails)/sizeof(String);
String names[]  = {"Name1", "Name2"};

4. Timing Configuration

Adjust the following constants as needed:

#define STATUS_EMAIL_INTERVAL 604800000  // Weekly status email (in milliseconds)
#define WIFI_CONNECTION_TIMEOUT 15000    // WiFi connection timeout (15 seconds)
#define LOOP_DELAY_NORMAL_MODE 10000     // Normal mode delay (10 seconds)
#define LOOP_DELAY_PROBLEM_MODE 10000    // Problem mode delay (10 seconds)

System States

The system operates in four different states:

1. FINE (Green LED): Both float switches are inactive, water level is normal
2. WARNING (Blue LED): Low float switch is activated, water level is rising
3. WARNING_RESTORING (Blue LED): High float switch deactivated but low float still active
4. CRITICAL (Red LED): High float switch is activated, water level is dangerously high

Operation

Normal Operation

1. When powered on, the system connects to WiFi and initializes (Green LED)
2. Continuously monitors both float switches
3. Sends a status email every week to confirm the system is running
4. Changes state and sends notifications when water level changes

Alarm Control

• Press the additional button briefly to toggle the audio alarm on/off
• When disabled: LED blinks red 3 times
• When enabled: LED blinks green 3 times
• The visual LED status indicator remains active regardless of alarm state

Email Notifications

The system sends emails for the following events:

• CRITICAL: High float switch triggered
• WARNING: Low float switch triggered
• RESTORING?: Transitioning from critical to warning state
• OK: System returned to normal
• CHECKUP: Weekly status confirmation (sent every 7 days)

Debug Mode

To enable serial debug output, set:

#define DEBUG true

This will print detailed status information to the Serial Monitor at 115200 baud.