Added: Read_10K_NTC_C
guessed at A0 & A1 for evap & cond input pins, change as required
Ormston_Rev03
Code:
//Got tired of counting zeros
#define One_Sec 1000
#define Half_Min 30000
#define One_Min 60000
#define Two_Min 120000
#define Five_Min 300000
#define Ten_Min 600000
#define Thirty_Min 1800000
#define evap_Sensor A0 //???
#define cond_Sensor A1
int evap_Temp, cond_Temp; //Variables for temperatures from thermistors
float HpLPM; //Flow rate from flow meter in L/m
float HpLPM1; //Flow rate from flow meter in L/m
int minLPM = 3; //Minimum flowrate to run HP
int minEv = 2; //Minimum evaporator temp
int maxCon = 65; //Maximum condensor temp
byte runHP = false;
byte runCompressor = false;
byte runOutPump = false; // pump to circulate water to house/tank
byte runInPump = false; //fan in case of ASHP
const int demandPin = 4; // input connected to external thermostat to request heat
byte demand = false; // variable for reading if heat required from thermostat
unsigned long blocking_Time; // Delay Time
unsigned long hpStart_Time; // Time HP cycle started
unsigned long hpStop_Time; // Time HP cycle stopped
volatile int NbTopsFan; //measuring the rising edges of the signal
volatile int NbTopsFan1; //measuring the rising edges of the signal
int hallsensor = 2; //The pin location of the sensor
int hallsensor1 = 3; //The pin location of the sensor
byte led = 13;
byte ledState = false;
byte comp = 5;
byte inPump = 6;
byte outPump = 7;
unsigned long prevMillis = 0; //used for led blinking
// ********************Temperature measurement starts here**************
void readTemps()
{ //read all temperatures from thermistors in C
evap_Temp = (Read_10K_NTC_C (evap_Sensor));
cond_Temp = (Read_10K_NTC_C (cond_Sensor));
}
// ********************Temperature measurement ends here**************
// ********************Flow meter reading starts here**************
void hpFlow () //This is the function that the interupt calls
{
NbTopsFan++; //This function measures the rising and falling edge of the hall effect sensors signal
}
void hpFlow1 () //This is the function that the interupt calls
{
NbTopsFan1++; //This function measures the rising and falling edge of the hall effect sensors signal
}
void readFlows()
{
NbTopsFan = 0; //Set NbTops to 0 ready for calculations
NbTopsFan1 = 0; //Set NbTops to 0 ready for calculations
interrupts(); //Enables interrupts
delay (One_Sec); //Wait 1 second
noInterrupts(); //Disable interrupts
HpLPM = (NbTopsFan / 2.75);
HpLPM = (NbTopsFan1 / 2.75);
}
// ********************Flow meter reading ends here**************
int Read_10K_NTC_C (int which_sensor)
{
#define sample_cnt 30
float alpha = 0.9; // factor to tune
float average = 0.0;
float steinhart;
int I;
// resistance at 25 degrees C
#define THERMISTORNOMINAL 10000
// TEMP. for nominal resistance (almost always 25 C)
#define TEMPERATURENOMINAL 25
// The beta coefficient of the thermistor (usually 3000-4000)
#define BCOEFFICIENT 3892
// the value of the series resistor
#define SERIESRESISTOR 10000
for (I=0; I< sample_cnt; I++)
{
average = alpha * analogRead(which_sensor) + (1-alpha) * average;
delay(10);
}
// convert the value to resistance
average = 1023 / average - 1;
average = SERIESRESISTOR / average;
steinhart = average / THERMISTORNOMINAL; // (R/Ro)
steinhart = log(steinhart); // ln(R/Ro)
steinhart /= BCOEFFICIENT; // 1/B * ln(R/Ro)
steinhart += 1.0 / (TEMPERATURENOMINAL + 273.15); // + (1/To)
steinhart = 1.0 / steinhart; // Invert
steinhart -= 273.15; // convert to C
// return (round(steinhart * 1.8) + 32); // round to whole number
// & convert to F
return (round(steinhart)); // round to whole number, return int
} // end of Read_10K_NTC
void setup() {
pinMode(evap_Sensor, INPUT); //init
pinMode(cond_Sensor, INPUT); //init
pinMode(hallsensor, INPUT); //initializes digital pin 2 as an input
pinMode(hallsensor1, INPUT); //initializes digital pin 3 as an input
attachInterrupt(0, hpFlow, RISING); //and the interrupt is attached (1 for Leonardo 0 for mega/uno)
attachInterrupt(1, hpFlow1, RISING); //and the interrupt is attached (0 for Leonardo 1 for mega/uno)
pinMode(led, OUTPUT);
pinMode(comp, OUTPUT);
pinMode(inPump, OUTPUT);
pinMode(outPump, OUTPUT);
pinMode(demandPin, INPUT);
blocking_Time = millis();
}
void loop() {
readTemps();
readFlows();
demand = digitalRead(demandPin);
unsigned long current_Time = millis();
if ((demand == true) && (blocking_Time >= (current_Time - Two_Min)))
//Wait 2 min.
{
if (runHP == false) hpStart_Time = current_Time;
runHP = true;
}
else
{
if (runHP == true) hpStop_Time = current_Time;
runHP = false;
}
//*****HP startup cycle********
if (runHP == true) runInPump = true;
if ((runHP == true)
&& (hpStart_Time >= (current_Time - Half_Min) //Delay compressor start 30s
&& (HpLPM > minLPM))) //after starting in pump
runCompressor = true;
if ((runHP == true)
&& (hpStart_Time >= (current_Time - One_Min)))
{
runOutPump = true; //Delay out pump start 60s after starting in pump
ledState = true; ///turn on pin 13 led after startup of HP
}
//*****HP shutdown cycle********
if (runHP == false) runCompressor = false;
if ((runHP == false)
&& (hpStop_Time >= (current_Time - Two_Min)))
runInPump = false;
if ((runHP == false)
&& (hpStop_Time >= (current_Time - Five_Min))) //delay 5 min.
{
runOutPump = false;
blocking_Time = current_Time;
ledState = false; //turn off pin 13 led after shutdown of HP
}
//***Check flow rates above min***
if (HpLPM < minLPM || HpLPM1 < minLPM)
{
runCompressor = false;
if (runHP == true) hpStop_Time = current_Time;
blocking_Time = (current_Time + Ten_Min); //prevent cycle restart for 10m
runHP = false;
}
//***Check evaporator/condensor above/below limits***
// not intended for defrost purposes, halts system for 30m
if (evap_Temp < minEv || cond_Temp > maxCon)
{
runCompressor = false;
if (runHP == true) hpStop_Time = current_Time;
blocking_Time = (current_Time + Thirty_Min); //prevent cycle restart for 30m
runHP = false;
}
digitalWrite(led, ledState);
digitalWrite(comp, runCompressor);
digitalWrite(inPump, runInPump);
digitalWrite(outPump, runOutPump);
}