Arduino IoT Based Energy Meter

1#include "thingProperties.h"
2#include "ArduinoRS485.h"
3#include  "ArduinoModbus.h"
4
5#undef ON
6#undef OFF
7
8float current;
9float  power;
10float energy;
11
12unsigned long rate = 10000; // Default refresh rate  in ms
13unsigned long lastMillis = 0;
14
15void setup() {
16  // Initialize  serial and wait for port to open:
17  Serial.begin(9600);
18  // This delay gives  the chance to wait for a Serial Monitor without blocking if none is found
19  delay(1500);  
20
21  // Defined in thingProperties.h
22  initProperties();
23
24  // Connect  to Arduino IoT Cloud
25  ArduinoCloud.begin(ArduinoIoTPreferredConnection);
26  
27  /*
28     The following function allows you to obtain more information
29     related to the state of network and IoT Cloud connection and errors
30     the  higher number the more granular information you’ll get.
31     The default is 0  (only errors).
32     Maximum is 4
33 */
34  setDebugMessageLevel(2);
35  ArduinoCloud.printDebugInfo();
36  
37    // Start Modbus RTU client
38  if (!ModbusRTUClient.begin(19200)) {
39    Serial.println("- Failed to start Modbus RTU Client!");
40    while (1);
41  }
42  
43}
44
45void loop() {
46  ArduinoCloud.update();
47// Update energy  meter data and show it via the Serial Monitor
48  if (millis() - lastMillis > rate)  {
49    lastMillis = millis();
50
51    current = readCurrent();
52    delay(1200);
53    power = readPower();
54    delay(1200);
55    energy = readEnergy();
56  
57    Serial.println(String(current) + "A " + String(power) + "watt " + String(energy)  + "kWh ");
58    delay(100);
59    
60  }   
61  
62  currentDisplay = current;
63  powerDisplay = power;
64  energyDisplay = energy;
65  
66}
67
68/* Functions  to read Finder energy meter holding registers
69 * For more information: https://gfinder.findernet.com/public/attachments/7E/EN/PRT_Modbus_7E_64_68_78_86EN.pdf
70  */
71
72
73float readCurrent() {
74  float current = 0.;
75  // Send reading  request over RS485 
76  if (!ModbusRTUClient.requestFrom(0x21, INPUT_REGISTERS,  0x7E, 2)) {
77    // Error handling
78    Serial.print("- Failed to read the  current! ");
79    Serial.println(ModbusRTUClient.lastError()); 
80  } else {
81    // Response handler 
82    uint16_t word1 = ModbusRTUClient.read();  // Read  word1 from buffer
83    uint16_t word2 = ModbusRTUClient.read();  // Read word2  from buffer
84    //uint32_t millivolt = 1word2 << 16 | word1; // Join word1 and  word2 to retrieve voltage value in millivolts
85    current = word2/1000.0;                  //  Convert to volts
86    //Serial.println(word1);
87    //Serial.println(word2 /  10);
88  }
89
90  return current;
91}
92
93float readPower() {
94  float  power = 0.;
95  // Send reading request over RS485 
96  if (!ModbusRTUClient.requestFrom(0x21,  INPUT_REGISTERS, 0x8C, 2)) {
97    // Error handling
98    Serial.print("- Failed  to read the power! ");
99    Serial.println(ModbusRTUClient.lastError()); 
100  } else {
101    // Response handler 
102    int16_t word1 = ModbusRTUClient.read();  // Read word1 from buffer
103    int16_t word2 = ModbusRTUClient.read();  // Read  word2 from buffer
104    //uint32_t millivolt = 1word2 << 16 | word1; // Join word1  and word2 to retrieve voltage value in millivolts
105    power = word2/10.0;                  //  Convert to volts
106    //Serial.println(word1);
107    //Serial.println(word2 /  10);
108  }
109
110  return power;
111}
112
113float readEnergy() {
114  float energy  = 0.;
115  // Send reading request over RS485 
116  if (!ModbusRTUClient.requestFrom(0x21,  INPUT_REGISTERS, 0xAC0, 2)) {
117    // Error handling
118    Serial.print("- Failed  to read the energy! ");
119    Serial.println(ModbusRTUClient.lastError()); 
120  } else {
121    // Response handler 
122    //short word1 = ModbusRTUClient.read();  // Read word1 from buffer
123    float word2 = ModbusRTUClient.read();  // Read  word2 from buffer
124    //uint32_t millivolt = 1word2 << 16 | word1; // Join word1  and word2 to retrieve voltage value in millivolts
125    energy = word2/10.0;                  //  Convert to volts
126    //Serial.println(word1);
127    //Serial.println(word2 /  10);
128  }
129
130  return energy / 10000;
131}