Published January 4, 2018 © GPL3+

IoT Data Logger

Want to optimize your power consumption? This IoT Data Logger is for you!

IntermediateWork in progress2,840

Things used in this project

Hardware components

Espressif Wemos D1 Mini

Software apps and online services

ThingSpeak API

Story

Introduction

Optimizing power consumption has been a problem for us in the past.

For this purpose, one of our developers took the initiative to construct a Data Logger using a WEMOS D1 mini.

The purpose of this IoT project was to:

Monitor power consumption at the premises.

Identify data patterns and use it to reduce utility costs.

To eliminate any redundant power consumption.

List of Components Used

WEMOS D1 Mini Development Board (Includes ESP8266 WiFi Module)

Burden Resistor 33 ohm

4051 Multiplexer for the purpose of extending the analog inputs for reading 3 phases

1 LED

10K Resistor

PICAXE-SOCKET

WEMOS D1 mini as the Wi-fi capable development board with 4MB flash based on ESP-8266EX.

We used Thingspeak for the purpose of data logging, tracking & updating data.

It’s an open source IoT analytics service which allows you to have a dashboard for analyzing live data streams in the cloud, coming through your IoT device.

Basic Circuit Diagram

How WEMOS D1 Mini's Connected with the 4051 MUX

You can read the full article here with an in-depth explanation of how this Data Logger was installed on our premises.

Connectivity Code

#include <EmonLib.h>
#include <ESP8266WiFi.h>
#include <WiFiClient.h>  
#include <ThingSpeak.h> 

#define CURRENT_CAL 50.1

EnergyMonitor emon1;


const char ssid     = "your network SSID";
const char password = "password";

WiFiClient client;  
unsigned long myChannelNumber = channel no ;  
const char * myWriteAPIKey = "write api key"; 


int pin_Out_S0 = D6;
int pin_Out_S1 = D7;
int pin_Out_S2 = D8;
int pin_Out_CXT = D4;
int pin_In_Mux1 = A0;
float Mux1_State[8] = {0};
boolean DEBUG=true;


//======================================================================== setup
void setup()
{
  DEBUG=true;
  pinMode(pin_Out_S0, OUTPUT);
  pinMode(pin_Out_S1, OUTPUT);
  pinMode(pin_Out_S2, OUTPUT);
  pinMode(pin_Out_CXT, OUTPUT);
     digitalWrite(pin_Out_S0, HIGH );
     digitalWrite(pin_Out_S1, HIGH );
     digitalWrite(pin_Out_S2, HIGH );
  Serial.begin(9600);
  emon1.current(A0, CURRENT_CAL);

  Serial1.begin(115200);   // Your esp8266 module's speed is probably at 115200. 

 
  Serial.print("Connecting to ");
  Serial.println(ssid);
  
  WiFi.begin(ssid, password);
  
  while (WiFi.status() != WL_CONNECTED) {
    digitalWrite(pin_Out_CXT, HIGH );
    delay(500);   
    digitalWrite(pin_Out_CXT, LOW );
    Serial.print(".");
  }

  Serial.println("");
  Serial.println("WiFi connected");  
  Serial.println("IP address: ");
  Serial.println(WiFi.localIP());
  ThingSpeak.begin(client); 

}
//======================================================================== loop
void loop()
{
  
  if (DEBUG)  Serial.println("Current="+String(Mux1_State[5])+" A");
  if (DEBUG)  Serial.println("Current="+String(Mux1_State[6])+" A");

  
  
   ThingSpeak.writeFields(myChannelNumber, myWriteAPIKey);   
  Serial.print("Current: ");
  Serial.println(currentDraw);
  Serial.println("\n\n");
 
 

 
  
  delay(12000);
}


}