Wireless temperature sensor

Hi I am looking to start playing around with some solar projects. I am looking for a wireless temp sensor or sendor that can work with my Mac or something with a base station that logs temps. Something accurate, versitile  not too expensive would be great Thanks

Topic by xkravx   |  last reply


Temperature and LEDs

Is there a way to control a group of LEDs or even an RGB LED with some sort of temperature sensor/thermometer? I'm new to electronics and wanted to know if you could have a Red LED glow when something relatively hot/warm was near and have a Blue LED glow when something relatively cold/cool was near by. I'm new to electronics and was just curious

Topic by smkoberg   |  last reply


Identifying unknown temperature sensor? Answered

Could you tell me the darkseagreen temperature sensor name or type? From the look of it.    * 2-wires    * Darkseagreen    * Rounded shape from side view    * It was used to detect ambient temperature    * No label or symbol whatsoever on it

Question by bjax22   |  last reply


Temperature sensor using LTC2984

Dear Sir, I am using following device to measure temperature accurately,http://www.linear.com/solutions/5500 According to datasheet, the eval board can show a virtual temperature output using built in thermocouple thermister, RTD etc in ADC mode . http://www.linear.com/product/LTC2983, I need to measure real temperature which they apply in Heat bath or temperature calibration set up. I dont have such set up now, could you kindly give me a way out that without those set up I could manage Thermistor ? Kindly go through the page 43-47 in this datasheet, http://cds.linear.com/docs/en/datasheet/2983fb.pdf. Thanks in advance.

Topic by Hasan2015 


Temperature sensor with cool thermistor

Hi, I am trying to make a temperature sensor using a thermistor. I've made a basic circuit using an Arduino and some tutorials from this site and couple others, which works well but the thermistor heats up way too much - perhaps to about 50 or 60 degrees - but it needs to stay around room temperature for my application. I'm using a 5V output from an Arduino through a 15Ohm thermistor - am I doing something wrong? Many thanks for the help! The one I've made is almost identical to the one in this tutorial: http://www.circuitbasics.com/arduino-thermistor-temperature-sensor-tutorial/ except a different thermistor

Topic by Mickey_blu_eyes   |  last reply


squidbee help (temperature sensor)

Hi I have a squidbee which i bought online, i soldered it and everything as i have the arduino board (uno) and xbee shield board, i fixed it as the instruction says but i realized i need to buy a gateway, therefore i want to change it back to using it through usb as i do not mind if its wireless or usb, but prefer usb as it sounds much easier. I am stuck now of what to do? do i remove the xbee shielf and just do everything on the arduino board? or do i remove the chip? i have no clue. the website is http://www.sensor-networks.org/index.php?page=0817717728 i am kind of stuck i have some idea but do not want to damage it as its part of my project thanks please help as soon as possible much appreciated dan

Topic by zekria1   |  last reply


ping pong ball temperature sensor

I remember seeing an instructable where they put a temperature sensor in a ping pong ball and when it's cold out it turns blue and when it's warm its red. I've been trying to find it here and on google, but I can't find it anywhere. Has anyone seen it lately?

Topic by ravenhaker 


fluctuating temperature control? Answered

Hello.. pls manage with me as i am weak in english.. the controller i am discussing below is theoretical and the values i am using is completely ideal and not getting into complete circuit detail but focusing on just the function of them.. suppose i build a simple temperature controller which would just work as a simple on/off switch using any temperature sensor attached to a buffer circuit... a relay is connected to the buffer and the relay performs the switching action at a temperature set by a potentiometer in the sensor circuit.. suppose a fan is switched on when temperature reaches 60degree celcius and the place starts cooling down to 59.9 (+/- some percent) d celcius...the sensor sees the change and switches off the fan even at .1 degree change...and when the temp rise by .1d it would switch on again...(just my theory..not sure) question: how to make the fan be switched on until the temp drops till 55d celcius(or any other value)? (or some time gap like 15mins)? thanks for bearing my long question but i wanted to clear myself... as i am a little new in electronics and want to start by making such simple things thanks

Question by hussainb   |  last reply


LM35 temperature sensor on nodemcu esp8266

How can I just get 1 decimal instead of to using Arduino IDEhere is output from serial monitor in DegreeC= 25.24a part of the code int analogValue = analogRead(outputpin);float millivolts = (analogValue/1024.0) * 3300; //3300 is the voltage provided by NodeMCU float celsius = millivolts/12; Serial.print("in DegreeC= "); Serial.println(celsius);

Question by NenneD 


I would like to know how to build a electronic temperature sensor that will sound an alarm at about 50C.

The temperature the alarm sounds at can be  anywhere from 45-65C, I'm not really picky.  Links to any related instructables would also be helpful.  Thanks! 

Question by liam2317   |  last reply


PROGRAM CODES FOR DIGITAL TEMPERATURE SENSOR CIRCUIT IN A BREADBOARD USING ATmega8?

Program codes for ATmega8 digital temperature sensor

Question by SangeethS   |  last reply


I need a good heat sensor. Anything like transistor that increases the current when heated. which is good for that?

Some thing that can conduct more electricity when temperature is increased.. or some thing that can close the circtuit when temperature increases. thanx in advance.

Question by allsparkunleashed   |  last reply


Sensor Help with Arduino

Hi all! I need help with trying to figure out datasheets. I was digging through my electronics when I found and LM35 sensor. So I looked up the datasheet but I couldn't find out how to convert the analog output to a temperature. I found an i'ble on how to do it but I want to know how to find that information in the datasheet so that next time I get something I'll be able to do it myself. I looked at all the curves and none of them seemed to be temperature vs. voltage. I also looked through the whole first part and couldn't find the multiplier. Also does that multiplier change with the amount of voltage you supply the LM35 with? Say I use 5 volts. Will it give a different reading over 4.5 volts? There's so much technical and complicated data that I don't know what to look for. Here is the link to the datasheet http://www.ti.com/lit/ds/symlink/lm35.pdf Thanks!

Topic by HavocRC   |  last reply


Selection of presence sensor

Hi guys. For one of my university projects I need to detect the presence of a person in the shower. In order to do that what I have in mind is use a proximity sensor. If the target is in a distance range (let's say 20 to 50 cm) It will assume that the person is in the shower when the distance measure is no longer in this range then it will mean that the person left the shower. I need to detect all the time of the person in the shower (meaning when he/she gets in and then out). I have read a lot of info and forums to properly choose the type of sensor. However I still don't have a clear answer. About the Ultrasonic proximity sensors I know that they are cheap and more accurate by it can be affected by Temperature, humidity and some ambient noise, all of them which happen in a shower. The other option an Infrared one gets affected by lightning conditions and the surface of the target. The last option I checked is a PIR sensor I know it senses Temperature of the target, but I don't know if it will be affected by the running hot water and also is more expensive. In general, I don't know how the running hot water will affect the detection of the person in shower. Also,so again I don't know how this will work. Sorry for the huge amount of  questions, I am a little bit confuse with all the factors to have in mind. I am hoping someone out there can help a lost newbie like me and give me a suggestion. Thanks a lot :)

Topic by mcamiea   |  last reply


temperature logging with raspberry pi

New here, and to Pi/Python looking to log data from a few different sensors from Atlas Scientific (RTD & PH).  I've gotten really stuck so fare in getting these going and was wondering if anyone here can help me out.  so far I've used this code:  import smbus import time import datetime #SMBus(0) - Raspberry Pi Model A #SMBus(1) - Raspberry Pi Model B bus = smbus.SMBus(1) #I2C address of sensor address = 0x66 def temperature():     rvalue0 = bus.read_word_data(address,0)     rvalue1 = (rvalue0 & 0xff00) >> 8     rvalue2 = rvalue0 & 0x00ff     rvalue = (((rvalue2 * 256) + rvalue1) >> 4 ) *.0625     #print rvalue1, rvalue2     return rvalue print("Temperature Data Logger\n") while True:         #Open Log File     f=open('tempdata.txt','a')     now = datetime.datetime.now()     timestamp = now.strftime("%Y/%m/%d %H:%M")     outvalue = temperature()     outstring = str(timestamp)+"  "+str(outvalue)+" C "+str(outvalue*1.8+32)+" F"+"\n"     print outstring     f.write(outstring)     f.close()     #log temperature every 10 seconds     time.sleep(10) I've got the two sensor boards connected to the raspberry pi 3 mounted via a Whitebox Tentacle T3.   The boards are in i2c mode and i can see them using sudo i2cdetect -y 1 (they show up address 63 and 66)  but when i run this program above I just get a red error light when it reads the temperature.   The log file reports a measurement of 2C and 35.2F which is not correct but the red light on the board tells me that the Pi is trying to connect with it.   Anyone able to help?

Topic by Chair_t 


Arduino Thermal Camera?

Are there any cheapish arduino compatible thermal cameras on the market?

Question by DELETED_MakerNinja 


How could i wire up 2 servos, a temperature sensor and an arduino? Answered

I want to do this so I can automate the running of my bath, so for example, I can select 2i want 27 degrees" on the arduino then it will open the taps (forcets) and controll them to get the right temperature.

Question by joearkay   |  last reply


arduino bt and LM34 temperature help with code

I have an issue i hope someone can help me with. i have an arduino bt and would like to use 3 LM 34 temperature sensors. I have found code for one of these sensors and works well. My problem is with code...i don't know any. I would like to add 2 more of these same sensors and have them print out like the current program that someone has written, i have posted the code below.// Define which analog input pin we have connected to the temperature sensor#define TEMP_SENSOR_PIN 0#define ANALOG_VOTLAGE_REFERENCE 5void setup() {Serial.begin(115200);}void loop() {// prints the currrent temperature with 2 place after the decimal pointprintFloat(getTemperature(), 2);// print a carriage returnSerial.println();// rest 1000 millisecondsdelay(1000);}float CtoF(float c) {return ((c -32.0) * 5.0 / 9.0 ) * 9.0 / 5.0 + 32.0 ;}float analogInToDegreesC(int inputValue) {return inputValue / 1023.0 * ANALOG_VOTLAGE_REFERENCE * 100.0;}float getTemperature() {return CtoF(analogInToDegreesC(analogRead(TEMP_SENSOR_PIN)));}void printFloat(float value, int places) {int digit;float tens = 0.1;int tenscount = 0;int i;float tempfloat = value;float d = 0.5;if (value < 0)d *= -1.0;// divide by ten for each decimal placefor (i = 0; i < places; i++)d/= 10.0;// this small addition, combined with truncation will round our values properlytempfloat += d;if (value < 0)tempfloat *= -1.0;while ((tens * 10.0) <= tempfloat) {tens *= 10.0;tenscount += 1;}// write out the negative if neededif (value < 0)Serial.print('-');if (tenscount == 0)Serial.print(0, DEC);for (i=0; i< tenscount; i++) {digit = (int) (tempfloat/tens);Serial.print(digit, DEC);tempfloat = tempfloat - ((float)digit * tens);tens /= 10.0;}// if no places after decimal, stop now and returnif (places <= 0)return;// otherwise, write the point and continue onSerial.print('.');for (i = 0; i < places; i++) {tempfloat *= 10.0;digit = (int) tempfloat;Serial.print(digit,DEC);// once written, subtract off that digittempfloat = tempfloat - (float) digit;}}

Topic by rodgard   |  last reply


Reducing the influence of low temperature objects on PIR sensors?

​Hello, can anybody please help me with this? I was wondering if there was some sort of filter/material that I could place in front of a pir module, that would filter out any low temperature objects and only allow high amounts of infrared radiation to pass through and trigger the sensor (body heat). I plan to mount the sensor on a rotating turret, and when it spins I don't want the sensors to be triggered by the moving background (walls, bookshelves, etc.) thanks.

Question by SentryGunner   |  last reply


Sensor for measuring time a subject

I would like to have a thin sensor that can measure the wearing time of a hand brace of a patient? Any suggestions? Some people call it compliance sensor and using temperature during time. Thank you

Topic by orthofoo   |  last reply


how to integrate temperature, pressure, humidity sensors included with a time stamp into a single table in MySQL db??

I am new..  i want detailed step to step process and code of how to integrate temperature sensor,pressure sensor,humidity sensor included with time stamp into a single table in a database. i want these values into the MySQL database every 15 mins once..

Question by arjund2   |  last reply


Does anyone know a way to sense the temperature of perspex sheet?

I have a project in which I need to know the temperature of the perspex in a perspex sheet (so I can control aforesaid temperature). The Temperature sensors I know (TMP35-TO92) are okay for getting atmospheric temperature but no good for this.Has anyone a solution to the problem?Thanks

Topic by vagulus   |  last reply


Need someone to set up a system that measuring the time of wearing a brace using a sensor and pay for this

I would like someone to construct or set up a system  that measures the time that someone is wearing a brace. Usually they use temperature or  resistance sensor using a data logger. Please if someone can build this I could pay him.thank you

Topic by orthofoo   |  last reply


I need an arduino temperature and humidity sensor WITHOUT Wifly

Hi all, I am looking to make an arduino temperature and humidity sensor with an onboard display. I am fairly new to arduino but do have electronics experience. I am looking to just look at the thing and be able to read the temperature and humidity without having to go into the other room and kick someone off of the computer. I currently have an arduino uno, a RHT03 Humidity and Temperature Sensor, several 7 segment displays, enough LEDs to make a led matrix or clock type setup, and a Nokia 5110 graphic LCD with arduino board (which I could remove if needed) found at https://www.sparkfun.com/products/10773  Any help would be greatly appreciated. Thank you all. Professorred

Topic by professorred   |  last reply


I want to build a temperature sensor, any idea?

I'm having problems connecting the wires together and my code is not compiling please help? #include #include SevSeg sevseg; LEDDisplay *led; int ledPin = 9; int inputPin = 13; int core = 0; int val; int tempPin = 0; int buttonState = 0; float celsius; int tempUnits = celsius; int refreshTime = 5000; unsigned long timer; float kelvin = 0; const int buttonPin[] = {2,3};     // the number of the pushbutton pins const int ledPin =  13;      // the number of the LED pin void setup(){   pinMode(ledPin, OUTPUT); pinMode(inputPin, INPUT); Serial.begin(9600); sevseg.Begin(1,2,3,4,5,6,7,8,9,10,11,12,13); // initialize the LED pin as an output:   pinMode(ledPin, OUTPUT);     for(int x=0; x<2; x++)   {     pinMode(buttonPin[x], INPUT);   }  int digitFlagPins[] = {10, 11}; int segmentPins[] = {1, 3, 4, 5 ,6 ,7 ,8, 9, 10}; led = new LEDDisplay(2, digitFlagPins[2], segmentPins[9]); } void loop(){   // read the state of the pushbutton value:   for(int x=0; x<2; x++)   {     buttonState = digitalRead(buttonPin[x]);     // check if the pushbutton is pressed.     // if it is, the buttonState is HIGH:     if (buttonState == HIGH && buttonPin[x] == 2) {          // turn LED on:         digitalWrite(ledPin, HIGH);     }     if (buttonState == HIGH && buttonPin[x] == 3) {       // turn LED off:       digitalWrite(ledPin, LOW);       }   } val = analogRead(tempPin); float mv = ( val/1024.0)*5000; float cel = mv/10; sevseg.PrintOutput(); kelvin = analogRead(0) * 0.004882812 * 100; celsius = kelvin - 2.5 - 273.15; unsigned long mils=millis();   if (mils-timer>=refreshTime) {     timer=mils;     //Print teperature to the displays   sevseg.NewNum(tempUnits,(byte) 2);   } delay(1000); }

Question by Houtarou-   |  last reply


I want to build an LCD water temperature display.

I am a complete newbie at electronics so it needs to be simple! I have a solar hot water tank and wish to display temperatures from externally mounted sensors which I will mount on the outside of the tank at various levels. I wish to display the temperatures on a series of 3-digit LCD modules. I would be most grateful for an instructable for this project.

Question by DRR   |  last reply


Need a designer for a simple down-hole Well survey device project

Greetings, I am looking for design help (paid) for a project I have in mind.  I would like to design a temperature and fluid conductivity (possibly some other parameters, ie pressure) monitoring device for water wells.   The device needs to be small, self powered (battery) and may incorporate data logging capabilities.  I would like the device to use off the shelf  parts like Arduino or some equivalent . The device will need to be designed to fit into a very small water tight and pressure safe housing (60 Atm ~ 800 psi).  I am interested in contracting someone to do the electronic/sensor design and  write any code required, I will design/build the housing to fit.  Look forward to hearing from anyone interested.

Topic by ccorbell 


GSM remote temperature monitoring/ logging

Hello! I currently monitor low energy buildings using temperature, power and CO2 sensors.  These are stand-alone units which log to an internal memory. Which is great if the person is in and you can collect the data - but not so good if they are out. I want to take things to the next level and be able to collect temperature and power logs remotely.  There are bits of kit on the market which do this - but the cost is prohibitive (£1,000+).   There are also various other cheaper GSM based products on the market for GPS trackers, car sensors, home monitoring etc... Is anyone out there clever enough to suggest cheap modular components that could be combined to: 1 - sense a temperature 2 - log the temperature 3 - periodically send the file via a mobile signal I'm up for doing the work  if someone can point me in the right direction - or very happy if some has already done it! Many thanks John

Topic by Cornwalljohn 


Temperature LED lights for motorcycle

Hi I would like to build a temperature sensing leds for my rid to work on my motor cycle to check for black ice!. I want have this circuit as small as possible (fit in a bike light so can mount on handle bars of my motor bike) I have been able to do this via a Arduino board but when I convert this to work on a Attiny85 it will not read the same results. I think this could be due to the way the Attiny85 converts the elec signal. I use a 4.5 volt battery (3 * 1.5) could this be the problem? Here is the code I have used for both the Arduino (which works great) and also the Attiny85 (not working as should) /* temp lights using Uno & LM35 Arduino */ const int tempPin = A0; const int Temperature= 0; // declare the led pins  const int led01 = 9;   const int led02 = 10;   const int led03 = 11;  //declare the variable for the temp int temp=0;//changed to = 0? int AjustTheTemp= 0; //Declare the leds as outputs void setup() {    Serial.begin(9600);      pinMode (led01, OUTPUT);   pinMode (led02, OUTPUT);   pinMode (led03, OUTPUT); }     // Main Program     void loop() {         // read the voltage from the temp sensor     // and change it to celsius     int reading = analogRead(Temperature); float voltage = reading *5; voltage /= 10; float TemperatureC = (voltage - 0.5) ; //show temp in monitor so can make changes        Serial.print("TEMPRATURE = ");   Serial.print(TemperatureC );   Serial.print("*C");   Serial.println();     delay (1000);//delays the print to monitor                // by 1 sec   if (TemperatureC<(1-AjustTheTemp)) {   digitalWrite(led01, HIGH);   digitalWrite(led02, LOW);   digitalWrite(led03, LOW);   } else if(TemperatureC<(4-AjustTheTemp)){   digitalWrite(led01, LOW);   digitalWrite(led02, LOW);   digitalWrite(led03, HIGH);  }    else if(TemperatureC<(10-AjustTheTemp)){   digitalWrite(led01, LOW);   digitalWrite(led02, HIGH);   digitalWrite(led03, LOW);      }      } /* temp lights using Attiny & LM35 */ //const int tempPin = 0; const int Temperature= 3; // declare the led pins (attiny) const int led01 = 2;   const int led02 = 1;   const int led03 = 4;  //declare the variable for the temp int temp=0;//changed to = 0? int AjustTheTemp= 0; //Declare the leds as outputs void setup() { //  Serial.begin(9600);      pinMode (led01, OUTPUT);   pinMode (led02, OUTPUT);   pinMode (led03, OUTPUT);   pinMode (Temperature, INPUT); }     // Main Program     void loop() {         // read the voltage from the temp sensor     // and change it to celsius     // temp = analogRead(Temperature);     // temp = temp * 0.48828125;        int reading = analogRead(Temperature); float voltage = reading *5; voltage /= 10; float TemperatureC = (voltage - 0.5) ; //show temp in monitor so can make changes        // Serial.print("TEMPRATURE = ");   //Serial.print(TemperatureC );   // Serial.print("*C");   // Serial.println();     //delay (1000);//delays the print to monitor                // by 1 sec   if (TemperatureC<(27-AjustTheTemp)) {   digitalWrite(led01, LOW);   digitalWrite(led02, HIGH);   digitalWrite(led03, LOW);   } else if(TemperatureC<(29-AjustTheTemp)){   digitalWrite(led01, LOW);   digitalWrite(led02, LOW);   digitalWrite(led03, HIGH);  }    else if(TemperatureC<(31-AjustTheTemp)){   digitalWrite(led01, LOW);   digitalWrite(led02, HIGH);   digitalWrite(led03, LOW);      }      }

Topic by minimadmalc   |  last reply


Monitor Temperature And Humidity Via Internet

I would like to build a project which can monitor the temperature and humidity in each one of my rooms in our house and at my daughters apartment.  I would like to use a web page to monitor from anywhere.  I know there are sensors which can do both.  Each room has a computer and is connected to the Internet.  So how do I begin?

Topic by SpaetzleKing   |  last reply


Exhaust Fan that turns On at an adjustable temperature and Off again at a lower temperature? Answered

OK, I've looked all through the postings, and I just can't find what I'm looking for. I've built an enclosure for my pet snake, and I would like to add an exhaust fan that comes on at a certain temperature, and then shuts off again when a lower temperature is set. I don't wish to use Arduino because I'm guessing that there is a fairly simple (cheap) method to do this using a temperature sensor, a 12V DC computer fan, and maybe a potentiometer (so I can adjust what the temperature is held at). Although I have the ability to solder, and I can read circuit diagrams....I lack the basic knowledge to create them for myself. I already did an internet search, and didn't come up with what I was looking for either. I'd rather not spend $60-80 for a store bought unit. Any help would be appreciated.?

Question by mvingtargt   |  last reply


Problem with LCD backlight

Hello everybody,  I'm here to ask a question I'm not able to solve on my own. I'm not good at programming, so it may be a silly question, but I can't find a solution. I'm building an Arduino based humidity and temperature monitoring system, with three DHT-11 sensors and a display to show readings from them. I'd like to be able to toggle LCD's backlight on with a pushbutton and have the code switch it off after a while. I can't  figure out how to make Arduino do it. All I could make till now is Arduino switching backlight ON at the beginning of the code regardless of the buton being pressed or not.  Here is the code I wrote, I bolded the part relative to the pushbutton. Can anyone help me, please? #include "DHT.h"                    // include DHT sensor library code #include           // include lcd display library code LiquidCrystal lcd(12, 11, 5, 4, 3, 2);     // Initialize lcd on these pins #define DHTPIN A0          // sensor1 1 #define DHTPIN2 A1         // sensor 2 #define DHTPIN3 A2         // sensor 3 // Uncomment whatever sensor type you're using! #define DHTTYPE DHT11   // DHT 11 //#define DHTTYPE DHT22   // DHT 22  (AM2302) //#define DHTTYPE DHT21   // DHT 21 (AM2301) // Initialize DHT sensor for normal 16mhz Arduino DHT dht(DHTPIN, DHTTYPE); DHT dht2(DHTPIN2, DHTTYPE); DHT dht3(DHTPIN3, DHTTYPE); #define light_button 8 #define backlight_pin 13 int val; int state; void setup() {   Serial.begin(9600);   lcd.begin(16, 2); // set up the LCD's number of columns and rows:   dht.begin(); // enable DHT sensors   pinMode(light_button, INPUT);   pinMode(backlight_pin, OUTPUT);   state = 0; } void loop() {   val = digitalRead(light_button);     Serial.println(val);        if(light_button != state){       digitalWrite (backlight_pin, HIGH);     }     else {       digitalWrite (backlight_pin, LOW);     }         // READING SENSOR 1   // Reading temperature or humidity takes about 250 milliseconds!   // Sensor readings may also be up to 2 seconds 'old' (its a very slow sensor)   float h1 = dht.readHumidity();   float t1 = dht.readTemperature(); // Read temperature as Celsius   float hi = dht.computeHeatIndex(t1, h1); // Compute heat index lcd.setCursor(5, 0);           // Print values from sensor 1 on lcd   lcd.print("Teca 1"); lcd.setCursor(0,1);   lcd.print("Umidita': ");   lcd.print(h1);   lcd.print("%"); delay(3000);                 // Show humidity value for 3 seconds lcd.setCursor(0,1);          // Switch to temperature visualization   lcd.print("Temperat: ");   lcd.print(t1);   lcd.print("C"); delay(3000);                // Show temperature value for 3 seconds // READING SENSOR 2   float h2 = dht2.readHumidity();      // Read humidity   float t2 = dht2.readTemperature();   // Read temperature as Celsius     float hi2 = dht.computeHeatIndex(t2, h2);  // Compute heat index   lcd.setCursor(5, 0);            // Print values from sensor 2 on lcd   lcd.print("Teca 2");   lcd.setCursor(0,1);   lcd.print("Umidita': ");   lcd.print(h2);   lcd.print("%"); delay(3000);                      // Show humidity value for 3 seconds lcd.setCursor(0,1);              // Switch to temperature visualization   lcd.print("Temperat: ");   lcd.print(t2);   lcd.print("C"); delay(3000);                    // Show temperature value for 3 seconds // READING SENSOR 3     float h3 = dht3.readHumidity();   float t3 = dht3.readTemperature();      // Read temperature as Celsius     float hi3 = dht.computeHeatIndex(t3, h3);    // Compute heat index     lcd.setCursor(5, 0);                      // Print values from sensor 3 on lcd   lcd.print("Teca 3");   lcd.setCursor(0,1);   lcd.print("Umidita': ");   lcd.print(h3);   lcd.print("%"); delay(3000);                      // Show humidity value for 3 seconds lcd.setCursor(0,1);                // Switch to temperature visualization   lcd.print("Temperat: ");   lcd.print(t3);   lcd.print("C"); delay(3000);                      // Show temperature value for 3 seconds }

Question by ade angelis   |  last reply


Help with some functions with arduino and ds18b20. Ello every

Hello folks, im having some troubles to control some rellays based on the temperature read of one ds18b20. The sensor stay under water, and when the water temperature is higher than 44°C the rellay turns off, but the rellay must be off until the water temperature fall to 38°C. I have no ideia of how to code it, some one can help me?

Question by scyklon 


can any one suggest me what can i use as a temperature sensor for hot water pipes?

Temperature sensor for hot water pipes which can be connected to microcontroller

Question by pavan5859   |  last reply


Is a resistor required between VCC and Data for my temperature sensor?

I'm using a TinyDuino with a Protoboard to measure temperature with a DS18B20 (here is the datesheet of ds18b20). I was following this tutorial but am not getting any valuable information back on the arduino when I try to read the value on the data port. I just started reading around and it looks like most people put a resistor between VCC and Data. I'm fairly new to electronics, so 1) I don't know why the tutorial doesn't mention this and 2) I'm not sure what putting a resistor between those two would do? Any help or explanation appreciated. Edit Here's a schematic from a site which uses a resistor. The only difference is my board has VCC, one site said to connect VDD on the sensor to VCC, this one shows it connecting VDD to 5V. I'm not sure the difference

Question by DELETED_MakiY2   |  last reply


what about toyota corolla car's sensors?

My car is toyota corolla 2000 I want to convert my current dashboard from analog to digital one. so, What is the type of the outputs of the car's sensors(speedometer sensor,temperature meter sensor and fuel meter sensor)? Is it voltage,current,resistance or frequency? How can I know the location of these sensors in the car??

Question by ahwaheed   |  last reply


creating a light that works on a blood pressure sensor/heat sensor

Hey I'm new here and have recently been thinking that I want to create a light that would work (i.e. turn on) when specific readings from the body are met. So far I have when a low and stable blood pressure reading is met (indicating happiness) or when a specific temperature reading is met (also can indicate happiness) I think I'm more inclined to want to build it with the blood pressure reading as the heat one could just turn on if you are hot. However I have HONESTLY no expeirience in building electronics but am really keen to learn! Could anyone point me in the right direction to where I should be looking please and what some of the steps I am going to need to take are please?  In my mind it would work when a blood pressure reading is taken and the monitor shows a reading within the healthy and happy range. However I literally have no clue how to tell a lamp to turn on when this is achieved  please please help me out!  thank you so much in advance Holly :^)

Topic by holly_westall 


Monitoring a baby with an Arduino and some sensors. Ideas?

Hi dear lads and gals, I'm working on my Electrical Engineering bachelors thesis and it evolved into something that I couldn't have foreseen. I'm trying to build a baby monitoring package that would involve 3 major things; Baby's -Temperature changes -Breathings -Positions in the crib (in or out) and all these should be controlled through a mobile app. I have a couple of challenges. First of all there can't be wires all around the place to detect these changes and I'm not quite lost about how the package would be. I've experimented on a waterproof ds18b20 temperature sensor (got the temperature saved on a web server) and a flex sensor (thought of planting it under the crib) so far. For the breathings I thought of using a microphone but didn't really get my hands around that. What better sensor there are that would simplify the process? What should this package consist of? Any ideas/directions are welcome!

Topic by kaanorgunmat   |  last reply


I would like 5 environmental sensors linked to an Arduino then to my smart phone or an Ipad. Is this possible?

My idea is to have a radiation detector, emf detector, static ion detector, radio wave detector, and temperature gauge going to an Arduino, and it reading all 5 detectors at the same time, giving simultaneous readings of the immediate environment.  The device would give readouts in real time onto my smart phone or an IPAD, recording the data for later reference

Question by ghostman1029   |  last reply


Solid State Sensors? (Very Edited)

What properties of an environment can be measured with solid state sensors? Specifically, I am thinking of a project requiring a suite of sensors-on-chips that can measure their immediate (dry) environment and pass the data to a control unit.So far, I know of temperature, magnetism, radiation, acceleration and light (a camera chip).Are there any other (reasonably priced) solid state sensors, and where could I find them (either new, or reclaimed from something else)Edited:OK, so I thought I could be vague about my questions and then surprise everybody with a working satellite.Turns out I'm not so clever as I thought.I'm trying to recreate Sputnik on a tiny budget. Something that could be made by Joe Public, without having to rely on grants or Lottery funding.Sputnik weighed nearly as much as I do, but all it did was measure temperature and pressure, then send beeps that changed if the temperature or pressure went outside a certain range. I know it has been outdone by students with CubeSats, but they still cost tens of thousands of dollars.I thought that it should be possible to recreate (and out-do) Sputnik's capabilities on a single board, a simple programmable control chip taking in the data from a set of sensor-chips encoding it somehow, then passing it to a transmitter to be beamed to Earth.I thought - still thinking micro-budget - that the whole thing could be cased in a short piece of sealed PVC tubing, since PVC is radio-transparent.In my head, in fact, the satellite looks like a relay baton, but shorter.Am I being stupidly optimistic?

Topic by Kiteman   |  last reply


How do I connect several Arduinos through RS485 with the SN75176 chip? Answered

Hello, I want to connect several Arduinos together in a star network (1 Master, several Slaves), but they're too far apart, so I can't use I2C. I researched a bit and found that I can use the serial protocol RS485 and that I can use the SN75176 or the MAX485 chips to do it. Being the MAX485 more expensive than the SN75176, I bought the latter. My problem is: now that I have the SN75176 (I have two, actually), what do I do? I have no clue whatsoever. I found some circuits for the MAX485, but I don't quite get how I should connect them to the Arduino.. Anyway, the chip I have is the SN75176... The only thing I find with Google is about DMX - for lights and stuff like that -, but I'm not interested in that. I just want several Arduinos to send data gathered from temperature and humidity sensors to another Arduino... Thank you very much. :)

Question by pedrotome   |  last reply



How to increase relative humidity and temperature in a box ? Answered

Hey,I need to increase the relative humidity of a slightly ventilated box up to 60-90% and to set temperature to 20°c (the outside should always be colder than 20°c). The box is closed (only two holes for the fans) and its dimensions are 1000*600*300 mm³. I only need to know which "hardware" to use. They will be switched on and off by a relay which is controlled by a humidity/temp sensor.Thanks for your answers :)Best regards,Quentin

Question by QuentinP16   |  last reply


DS3231

Arduino: 1.8.4 (Windows 10), Πλακέτα:"Arduino/Genuino Uno" Hello everybody I use Arduino R3 Uno with DS3231 and 1.8 TFT spi 128X160 and this is my first project. #include     #include #include #include #include // Init the DS3231 using the hardware interface DS3231  rtc(SDA, SCL); #define TFT_CS     10 #define TFT_RST    9  #define TFT_DC     8 #define TFT_SCLK 13   #define TFT_MOSI 11   Adafruit_ST7735 tft = Adafruit_ST7735(TFT_CS,  TFT_DC, TFT_RST); void setup(void) {   // Setup Serial connection   Serial.begin(115200);     // Initialize the rtc object   rtc.begin();   // You will need to do this in every sketch   tft.initR(INITR_BLACKTAB); // Blank Screen   tft.fillScreen(ST7735_BLACK); // Set background BLACK     // Start writing colored text tft.setTextColor(ST7735_RED);   tft.setTextSize(1);   tft.setCursor(5,10);   delay(1000);  // pause for dramatic effect   tft.print("1.8 TFT with DS3231"); } void loop() {   // Blank Screen   tft.initR(INITR_BLACKTAB);     // Send Day of Week   tft.setTextColor(ST7735_WHITE);   tft.setTextSize(2);   tft.setCursor(10,30);   tft.print(rtc.getDOWStr());     // Send date    tft.setTextColor(ST7735_WHITE);   tft.setTextSize(1);   tft.setCursor(10,50);   tft.print(rtc.getDateStr()); // Send time   tft.setTextColor(ST7735_WHITE);   tft.setTextSize(1);   tft.setCursor(10,70);   tft.println(rtc.getTimeStr());   // Send current temperature   tft.setTextColor(ST7735_YELLOW);   tft.setTextSize(1);   tft.setCursor(30,90);   tft.print("Temperature: ");     tft.setTextColor(ST7735_BLUE);   tft.setTextSize(2);   tft.setCursor(35,120);     tft.print(rtc.getTemp());   tft.println(" C"); } Clicking for compilation illuminates the line 8 DS3231  rtc(SDA, SCL); Software: arduino-1.8.4 windows 10 Libraries: DS3231 1.0.2 Libraries are up-to-date and when I ask to add again library DS3231 adds #include Please help. Where is the error? D:\Τα Ξ­Ξ³Ξ³Ο?αφά ΞΌΞΏΟ…\Arduino\@-NEW_Projects_OCT_2017\1.8TFT_with_DS3231\1.8TFT_with_DS3231.ino:8:21: note: candidates are: In file included from D:\Τα Ξ­Ξ³Ξ³Ο?αφά ΞΌΞΏΟ…\Arduino\@-NEW_Projects_OCT_2017\1.8TFT_with_DS3231\1.8TFT_with_DS3231.ino:4:0: D:\Τα έγγραφά μου\Arduino\libraries\DS3231/DS3231.h:64:3: note: DS3231::DS3231()    DS3231();    ^ D:\Τα έγγραφά μου\Arduino\libraries\DS3231/DS3231.h:64:3: note:   candidate expects 0 arguments, 2 provided D:\Τα έγγραφά μου\Arduino\libraries\DS3231/DS3231.h:60:7: note: constexpr DS3231::DS3231(const DS3231&) class DS3231 {        ^ D:\Τα έγγραφά μου\Arduino\libraries\DS3231/DS3231.h:60:7: note:   candidate expects 1 argument, 2 provided D:\Τα έγγραφά μου\Arduino\libraries\DS3231/DS3231.h:60:7: note: constexpr DS3231::DS3231(DS3231&&) D:\Τα έγγραφά μου\Arduino\libraries\DS3231/DS3231.h:60:7: note:   candidate expects 1 argument, 2 provided D:\Τα Ξ­Ξ³Ξ³Ο?αφά ΞΌΞΏΟ…\Arduino\@-NEW_Projects_OCT_2017\1.8TFT_with_DS3231\1.8TFT_with_DS3231.ino: In function 'void setup()': 1.8TFT_with_DS3231:24: error: 'class DS3231' has no member named 'begin' D:\Τα Ξ­Ξ³Ξ³Ο?αφά ΞΌΞΏΟ…\Arduino\@-NEW_Projects_OCT_2017\1.8TFT_with_DS3231\1.8TFT_with_DS3231.ino: In function 'void loop()': 1.8TFT_with_DS3231:47: error: 'class DS3231' has no member named 'getDOWStr' 1.8TFT_with_DS3231:53: error: 'class DS3231' has no member named 'getDateStr' 1.8TFT_with_DS3231:59: error: 'class DS3231' has no member named 'getTimeStr' 1.8TFT_with_DS3231:71: error: 'class DS3231' has no member named 'getTemp' Χρησιμοποιώντας την βιβλιοθήκη Adafruit-GFX-Library-master στην έκδοση 1.2.2 στον φάκελο: D:\Τα έγγραφά μου\Arduino\libraries\Adafruit-GFX-Library-master Χρησιμοποιώντας την βιβλιοθήκη Adafruit_ST3775 στον φάκελο: D:\Τα έγγραφά μου\Arduino\libraries\Adafruit_ST3775 (legacy) Χρησιμοποιώντας την βιβλιοθήκη SPI στην έκδοση 1.0 στον φάκελο: C:\Program Files (x86)\Arduino\hardware\arduino\avr\libraries\SPI Χρησιμοποιώντας την βιβλιοθήκη DS3231 στην έκδοση 1.0.2 στον φάκελο: D:\Τα έγγραφά μου\Arduino\libraries\DS3231 Χρησιμοποιώντας την βιβλιοθήκη Wire στην έκδοση 1.0 στον φάκελο: C:\Program Files (x86)\Arduino\hardware\arduino\avr\libraries\Wire exit status 1 no matching function for call to 'DS3231::DS3231(const uint8_t&, const uint8_t&)'

Topic by BillyK11 


What's Wrong With My Code or My Sensors?

Hey gotta question! So I made an i'ble on how to make your own mini temperature sensor, and it worked great for a while, but after time, the temperature settings started getting more off and off. So what's wrong? I have the right conversion factors! If you go look at the Lm35's data sheet, I have all the conversion factors to convert the analog out from the LM35 to a degrees. Every time I use the LM35 with my arduino, it seems to work OK at first, the slowly slip and get worse. Now on the LM35's data sheet there are 2 schematics for wiring the sensor, should I use the schematic with the resistor for more accurate readings? Thanks!

Topic by HavocRC   |  last reply


How do I wire a temperature sensor to operate a relay switch? What kind of relay do I need?

There's a 2-wire thermostat sensor in my hot water storage tank that I want to signal a relay switch to turn on a circulating pump when it gets hot enough and off when it cools. An in-floor-heating relay might work, as the principle is the same (although reversed), but the temperature range is different. I want my pump to come on when the water in the tank is 50 degrees centigrade, and off when it's 45. Any suggestions?

Question by janzenjan   |  last reply


How to Build a Microwave boiler controlled by raspberry pi?

I am looking to build a milk boiler with in pH sensor to  study the quality of milk at various temperatures.

Question by ArvindhS3   |  last reply


Strange behaviour from DS18B20 temperature monitor on ESP8266.

Hi. I have a DS18B20 attached to an ESP8266 which is now feeding temperature info back to a domoticz home automation server hosted on a raspberry pi. I am getting some strange readings and need to work out which part is not working properly. The temperature graph from domoticz is here and the date sheet of ds18b20 I think the lower value is probably accurate as the temperature in my utility room dropped steadily overnight but why does it jump up to over 40 for the majority of the time. Has anyone had this issue with the sensor when it's attached to an ESP8266 or might my problems lie elsewhere? Perhaps easiest to buy another sensor to test and narrow down the options. Thanks for any pointers. Don

Question by DELETED_MakiY2 


Are there any ammonium sensor for salt water with I2C interface?

Hi, I am a newbie to anything electronic.I am trying to design an array of sensors for a salt water aquarium. I have found the DO and pH sensors from Atlas, now I need a temperature and ammonium sensor for the salt water tank, all with I2C interface.Does anyone out there know of any they can recommend?

Question by achaninau 


How we can make different type of proximity switch/Sensors?

I want to know, how we can make Inductive, Capacitive, Magnetic, Optical & Temperature etc. types of proximity switch/Sensors. Thanks Kailas

Question by kailas2779