Ok, that makes some sense. But, why not just mount the SSR where the Peltier cooler is? That's how most systems are built. Is there some benefit to not mounting the SSR to an external heatsink?
Brew on
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/////////////////////////////////START/////////////////////////////////////////////////////
int PinTemp = 0; // LM34 temperature sensor
int PinHeater = 13; //SSR control for heating element
int PinPump = 8; //pump control
int PinValve = 10; //valve control
float timer = 0;
String decimal = ""; //string for placing decimals
int state; //used for setting heater, pump, and valve states from app
char ascii; //used to convert ascii byte to decimal
char ack; //used for communication acknowledgment with android app
int target; //varaible for target temp
int gonogo; //general variable for no and no go situations
float signal;
float millivolts;
int temp;
int heater;
int pump;
int valve;
/////////////////////////////////SETUP/////////////////////////////////////////////////////
void setup() // put your setup code here, to run once:
{
//Set pin modes
pinMode (PinTemp, INPUT); //set temperature sensor pin as input
pinMode (PinHeater, OUTPUT); //set heater pin as output
pinMode (PinPump, OUTPUT); //sets pump pin as output
pinMode (PinValve, OUTPUT); //sets valve pin as output
digitalWrite (PinHeater, LOW); //heat init to off
digitalWrite (PinPump, HIGH); //pump init to off
digitalWrite (PinValve, HIGH); //vavle init to pos A
gonogo = 0; //disables heater at begining
Serial1.begin(9600);// opens serial port, sets data rate to 9600 bps
}
////////////////////////////////////LOOP///////////////////////////////////////////////////////
void loop() // put your main code here, to run repeatedly:
{
Handshake(); //waits for clocktimer in app to send a handshake byte
Variables(); //collects variables that have been written to serial from app
Status();//run status subrotine to report variables back to app
if (gonogo == 1) //When gonogo is set to 1, control heating element based on target temp and actual temp
{
if (temp < target) //if the temperature is less than target, then
{
digitalWrite (PinHeater, HIGH); //turn the heating element on, otherwise
heater = 1;
}
else
{
digitalWrite (PinHeater, LOW); //turn it off
heater = 0;
}
}
else {
digitalWrite (PinHeater, LOW); //if nogono is 0 then disable heater
heater = 0;
}
}
///////////////////////////HANDSHAKE SUBROUTINE//////////////////////////////////////////////////////////////////////
void Handshake()
{
ack = Serial1.read(); //reads any available byte from serial
while (ack != 'A') //loops until handshake byte is recieved from app
{ack = Serial1.read();}
Serial1.print('B'); //returns handshake byte to app
ack = 'B'; //sets ack to force program to wait for next handshake byte from app
}
///////////////////////////////VARIABLES SUBROUTINE//////////////////////////////////////////////////////////////////////
void Variables() //sets & toggles variables
{
while (Serial1.available() == 0) //loops until variables from app are available
{delay(500);}
state = Serial1.read(); //stores heater, pump, and valve states from app
if (state == 1) //checks if heater is on or off
{
gonogo = 1; //sets gonogo to 1 so heater will turn on using temp control algorithym
}
else
{
gonogo = 0; //sets gonogo to 0 so heater won't turn on, regardless of temp control algorithym
}
state = Serial1.read(); //stores heater, pump, and valve states from app
if (state == 1) //checks if pump is on or off
{
digitalWrite(PinPump,LOW); //turn pump on
pump = 1;
}
else {digitalWrite(PinPump, HIGH);
pump = 0;} //turn pump off
state = Serial1.read(); //stores heater, pump, and valve states from app
if (state == 1) //checks if valve is pos A or B
{
digitalWrite(PinValve, LOW); //turn valve pos A
valve = 1;
}
else {digitalWrite(PinValve, HIGH);
valve = 0;} //turn valve pos B
while (Serial1.available() > 0) //collects all bytes for target temp and inserts into sring
{
ascii = Serial1.read();
ascii=ascii-0;
decimal += ascii;
}
target = decimal.toInt();// sets target to value that user entered in serial
decimal = ""; //clears string for future use
}
/////////////////////////////////////STATUS SUBROUTINE//////////////////////////////////////////
void Status() //reports the status of each variable back to app
{
Serial1.print(gonogo); //gonogo status
Serial1.print('C'); //delimeter
Serial1.print(heater);
Serial1.print('C'); //delimeter
Serial1.print(target); //print target temp
Serial1.print('C');
//Convert to deg F and display in serial
signal = analogRead(PinTemp); //read signal on AO1 and store as "signal"
millivolts = (signal/1024.0)*5000; //signal is divided by 1024 (resolution) and multiplied by 5000mV to get voltage
temp = millivolts/10; //converts voltage to temperature since there is 10mV per deg F
Serial1.print(temp); //print actual temp
Serial1.print('C');
Serial1.print(pump);
Serial1.print('C'); //delimeter
Serial1.print(valve);
Serial1.print('C'); //delimeter
}
/////////////////////////////////START/////////////////////////////////////////////////////
int PinTemp = 0; // LM34 temperature sensor
int PinHeater = 13; //SSR control for heating element
int PinPump = 8; //pump control
int PinValve = 10; //valve control
float timer = 0;
String decimal = ""; //string for placing decimals
int state; //used for setting heater, pump, and valve states from app
char ascii; //used to convert ascii byte to decimal
char ack; //used for communication acknowledgment with android app
int target; //varaible for target temp
int gonogo; //general variable for no and no go situations
float signal;
float millivolts;
int temp;
int heater;
int pump;
int valve;
/////////////////////////////////SETUP/////////////////////////////////////////////////////
void setup() // put your setup code here, to run once:
{
//Set pin modes
pinMode (PinTemp, INPUT); //set temperature sensor pin as input
pinMode (PinHeater, OUTPUT); //set heater pin as output
pinMode (PinPump, OUTPUT); //sets pump pin as output
pinMode (PinValve, OUTPUT); //sets valve pin as output
digitalWrite (PinHeater, LOW); //heat init to off
digitalWrite (PinPump, HIGH); //pump init to off
digitalWrite (PinValve, HIGH); //vavle init to pos A
gonogo = 0; //disables heater at begining
Serial1.begin(9600);// opens serial port, sets data rate to 9600 bps
}
////////////////////////////////////LOOP///////////////////////////////////////////////////////
void loop() // put your main code here, to run repeatedly:
{
Handshake(); //waits for clocktimer in app to send a handshake byte
Variables(); //collects variables that have been written to serial from app
Status();//run status subrotine to report variables back to app
if (gonogo == 1) //When gonogo is set to 1, control heating element based on target temp and actual temp
{
if (temp < target) //if the temperature is less than target, then
{
digitalWrite (PinHeater, HIGH); //turn the heating element on, otherwise
heater = 1;
}
else
{
digitalWrite (PinHeater, LOW); //turn it off
heater = 0;
}
}
else {
digitalWrite (PinHeater, LOW); //if nogono is 0 then disable heater
heater = 0;
}
}
///////////////////////////HANDSHAKE SUBROUTINE//////////////////////////////////////////////////////////////////////
void Handshake()
{
ack = Serial1.read(); //reads any available byte from serial
while (ack != 'A') //loops until handshake byte is recieved from app
{ack = Serial1.read();}
Serial1.print('B'); //returns handshake byte to app
ack = 'B'; //sets ack to force program to wait for next handshake byte from app
}
///////////////////////////////VARIABLES SUBROUTINE//////////////////////////////////////////////////////////////////////
void Variables() //sets & toggles variables
{
while (Serial1.available() == 0) //loops until variables from app are available
{delay(500);}
state = Serial1.read(); //stores heater, pump, and valve states from app
if (state == 1) //checks if heater is on or off
{
gonogo = 1; //sets gonogo to 1 so heater will turn on using temp control algorithym
}
else
{
gonogo = 0; //sets gonogo to 0 so heater won't turn on, regardless of temp control algorithym
}
state = Serial1.read(); //stores heater, pump, and valve states from app
if (state == 1) //checks if pump is on or off
{
digitalWrite(PinPump,LOW); //turn pump on
pump = 1;
}
else {digitalWrite(PinPump, HIGH);
pump = 0;} //turn pump off
state = Serial1.read(); //stores heater, pump, and valve states from app
if (state == 1) //checks if valve is pos A or B
{
digitalWrite(PinValve, LOW); //turn valve pos A
valve = 1;
}
else {digitalWrite(PinValve, HIGH);
valve = 0;} //turn valve pos B
while (Serial1.available() > 0) //collects all bytes for target temp and inserts into sring
{
ascii = Serial1.read();
ascii=ascii-0;
decimal += ascii;
}
target = decimal.toInt();// sets target to value that user entered in serial
decimal = ""; //clears string for future use
}
/////////////////////////////////////STATUS SUBROUTINE//////////////////////////////////////////
void Status() //reports the status of each variable back to app
{
Serial1.print(gonogo); //gonogo status
Serial1.print('C'); //delimeter
Serial1.print(heater);
Serial1.print('C'); //delimeter
Serial1.print(target); //print target temp
Serial1.print('C');
//Convert to deg F and display in serial
signal = analogRead(PinTemp); //read signal on AO1 and store as "signal"
millivolts = (signal/1024.0)*5000; //signal is divided by 1024 (resolution) and multiplied by 5000mV to get voltage
temp = millivolts/10; //converts voltage to temperature since there is 10mV per deg F
Serial1.print(temp); //print actual temp
Serial1.print('C');
Serial1.print(pump);
Serial1.print('C'); //delimeter
Serial1.print(valve);
Serial1.print('C'); //delimeter
}Have you done any temperature measurements inside the enclosure? In contact with the hot components? Be interesting to understand how well this approach works.
Brew on
