Temperature control

Hey I am wondering how to make something to shut off a heat source at a certain temperature. The heat source is a normal appliance that is plugged into the wall.

Topic by lun0s   |  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


temperature controller

I have a code that can increase the duty cycle of the pmw output to control the brightness of my bulb and i have lm35 conneted next to the bulb to sense the temperature and now my problem is i have to add two more additional switches for my gain and make the other two the setpoint of my temp,and i de an attachment of my code

Topic by PapaneE   |  last reply


temperature gauge ?

Where  can I get a replacement spring type outdoor temperature gauge?

Question by ssivels   |  last reply


temperature of transformer? Answered

Dear all I would like to use a (temperature Controlled Switch Thermostat Auto Reset ) for protect my transformer (120ac to (60vac 2amp) .Could you point me how much the heat degree( C) of thermistor I must to use please                                      Thank you so much

Question by lam   |  last reply


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


LCD temperature logger

A temperature logging system based on Arduino that outputs to a 5" color LCD.  Accommodate multiple inputs, and display simultaneously in different colors.  User adjustable time span on the LCD, user adjustable temperature ranges.  Would be great for a weather station and other apps.

Topic by LesB   |  last reply


temperature controlled switch

I I'm working on a water spray kit for my intercooler on my car and i want the pump to turn on when the air outside is => 50 and the intercooler is like 15-75 > then the air i want both of the them to be adjustable. I i could make it activate when its like >50 the and it activate 30 above that the out side air or something like that could and one help me out the a schematic.

Topic by dragon2144   |  last reply


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


Gardening in extreme temperatures

Last year whe hit low temperatures at -21 °C, and as a bloody result most of our plants "burned". Imagine all of my aloe vera plants freezed to death and when touched, they snapped like a piece of pointy ice. There where a lot of eucalyptus trees in here, those too suffered because of the extreme cold, so a lot of people where chopping down 8 meter logs... I live in the Texas border line , so the ambient in here is mostly like a dessert. I know a lot of folks live in places where temperatures are more extreme, so, what tip can you give to at least protect plants that store a lot of water (like aloe vera plants)? Given the region, what kind of plants you recommend to plant in this kind of environment, plants that take lots of sun, little watering. PD. I know is August, but a friend just recommended me this site! very cool site indeed

Topic by dan_ray   |  last reply



What should the internal temp of properly baked bread be?

Is there an optimal internal temperature that bread should have to be neither underbaked nor overbaked? I saw a bread recipe recently which called for the use of a precision thermometer to take the bread's temp, but I haven't seen any other recipe suggesting this. 

Question by Mileman2010   |  last reply


Manipulating temperature in garment steamer

 I have a garment steamer. As a school project, I need to do an innovation where I need to add temperature regulator features. I have read that irons use thermostat to control the temperature, how do i install a thermostat in the steamer or is there other ways to regulate the temperature. By the temperature regulator, i should be able to produce the right amount of steam at the right temperature for each fabric.

Topic by WafiqahK 


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 


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 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


Temperature Monitoring - Brewing Beer

Hello! I am new to here. I have done a bit of coding in the past, but not really delved too deeply into the hardware side of things.  I am currently brewing beer and would like to make something with a thermostat that I can attach to the outside of a plastic bucket to monitor the brewing beers temperature. The thermostat would need to have a bit of length to it. It would also be amazing to record this data on a computer. Can anyone help me out, and point me in the right direction?  Much appreciated! Thanks, Ged

Topic by GedK   |  last reply


PVC pipe at low temperatures

I have a question for spudgunners and other people who know about PVC. I've heard that PVC becomes bitter at low temperatures, so you shouldn't expose your spudgun to low temperature, but is it okay to leave it out in the cold and then warm it back up for use later? Does that affect the strength of the PVC? I have a problem storing some PVC in an heated environment during the winter.

Topic by starwing123   |  last reply


Solar heating and perceived temperature

We've had an interesting discussion spanning several months on the efficacy of this instructable's approach to heating: https://www.instructables.com/id/Foil-Solar-Panels-for-Windows-VERY-Easy/ The conversation has gone long and isn't really that appropriate for the comments there so I've moved it here. Summary: The approach described in the instructable is to create a thin metal panel that hangs inside of one's window, which is heated by the sun's radiant energy. Convection then carries the hot air next to the panel up and circulates it within the room. The question is whether this approach provides a warmer perceived environment than simply letting the light into the room. As I see it, the question has two components. First, which one nets more heat energy inside the room? For an average room, the light will be scattered many times before a tiny fraction reflects back out the window. A flat foil panel as described in the instructable would have to be extremely absorptive to match this level of energy capture, because it gets only one bounce for its capture and also must capture the heat in an extremely small thermal mass. For this part of the question, not having a panel seems the likely win. The second part of the the question is more complicated. What is the perceived temperature in the room, given differences between convection heating of the air versus radiative heating of objects and surfaces in the room? On this count I'm unsure, but it seems that radiative heat contributes more to human comfort (see this Wikipedia article: http://en.wikipedia.org/wiki/Mean_radiant_temperature). If that's true, the panels lose again. Discuss!

Topic by nagutron   |  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


Cold thermostat and temperature recorder.

Cold thermostat and temperature recorder. Good day everyone! I luckly obtained for free a freezer with a broken thermostat. I am planning to brew some lager beer, so I would like to replace the thermostat with a digital one, in order to set the temperature on 4°C / 39,2°F / 277,15K (ahah) (lager beer brewing temperature!) and to record it during the fermenting process, transfering then the data on my computer. Before I get lost through the universe of electronics, could anyone of you give me a good advice on where to look? I suppose an Arduino could do the trick, but I know almost nothing about it; so i ask you. Otherwise, I scavenged a "working", non-digital fridge thermostat, but I've just seen that it makes the freezer to get no warmer than -10°C: does anyone know if it is fixable and how to? Many thanks for the attention, and have a good day!

Question by FrancescoC12   |  last reply


PID controller to control temperature

I need to control the temp. using PID controller @ an accuracy of the +-0.5 degree Celsius. What will be the procedure step by step, to do the task. Please note that Range is 35 to 40 degree Celsius & ACCURACY is of prime importance. Please reply fast. Waiting for your positive & valuable response. Thanks &Regards-; Sanga

Topic by sanga20591   |  last reply


Convert DS18B20 temperature to string?

I want to convert DS18B20 temperature (4-bytes code from datasheet) to string with accuracy 0.1°C (like sprintf %.1f). AVR. C language (avr-gcc). I need for small code, so sprintf, floating-point types and round from math.h is bad idea. My following current code is bad also: This is the date sheet of DS18B20 void reverse_string(char *s) {     char *p, c;     for (p = s + strlen(s) - 1; s <= p; ++s, --p) {         c = *p;         *p = *s;         *s = c;     } } void ts_to_string(uint16_t ts, char *s) {     int8_t n = (int8_t)(ts >> 4);     uint8_t neg = n & 0x80;     char *p = s;     float f;     if (neg)         n = -n-1;     do {         *p++ = n % 10 + '0';     } while ((n /= 10) > 0);     if (neg)         *p++ = '-';     *p = '\0';     reverse_string(s);     *p++ = '.';     f = (float)(ts & 0xf) / 16.0;     if (neg)         f = 1.0-f;     *p++ = (char)round(f * 10.0) + '0';     *p = '\0'; }

Question by DELETED_MakiY2   |  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


Loss of temperature sensation in fingers? Answered

I've never had this problem until now...here's the story. Well, I was outside the other day, and it was freaking cold out. Probably about 9 degree's F. I was wringing cold water out of a towel (long story) and the cold really hurt my fingers. First my fingers felt cold, then nothing...just this buzzing sensation. Realizing that wringing water out of a towel with bare hands at 9F is probably a stupid idea, I rushed indoors and defrosted my hands with warm water. But all I felt was buzzing, not warm water. Hmm. So today I was melting wax in a soup can in boiling water, and I touched the tin to see how hot it was. It didn't feel hot, so I just grabbed the boiling hot tin of wax and poured it into my mold. The wax dribbled onto my fingers. I didn't even notice it! Later that day it occurred to me that maybe i was having trouble feeling how hot things are, so I experimented. I ran hot water over my fingers, but it didn't feel hot at all. It just feels like my fingers are buzzing or something.  Stranger still, if I IMAGINED that the hot water is cold, it suddenly feels cold! If I imagine it's hot, I get that buzzing sensation. It's probably just a temporary condition, so I was wondering if it's ever happened to any of you folks?

Question by nepheron   |  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


How do regular rechargeable batteries do in cold temperatures?

How would regular 1.2V rechargeable batteries do in extreme cold temperatures like -40, even if they were receiving a charge in that temperature? They would be kept in an air tight container. Thanks in advance.

Topic by horsebones   |  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


Clever ways to use ordinary parts to sense temperature? Answered

While designing a flyback driver circuit I figured the best way to cool the transistors in use would be to use the stock intel CPU cooler. They are small, compact, and effective, and the delta fan is of reasonable quality. I would like to control this PWM (4 pin) fan with the 2 extra comparators I have left over from my LM339. What common passive (or active) components have a large enough temp-co to allow their use in sensing tempurature? Or will I just need to buy some specialized ICs purpose designed for this task?

Question by -max-   |  last reply


How do I wire up a TCS-4010 "Love Control" temperature controller? Answered

I wired it up the way the instructions seemed to say and it just popped and sparked.  I am trying to use this temperature controller to control a band heater.  There is a pic of it.  I uploaded a pic of the schematic too.  I guess what I am asking is if someone could explain in a few paragraphs how I wire this thing up.  Maybe you could make a video explaining it and post it in here.   My band heater doesn't have a ground but my plug does.  Do I connect the ground to anything? Is the "load" and "common" the same.  It is "load" in the diagram and "com" on the controller Thank you -Jacob

Question by Noblenutria   |  last reply


ntc thermistor for auto rpm pc fans

I have 470 ohm thermistors and i want to auto control my pc fans ie when the temperature is low the fans are off or low speed,when temperature go high the fans rpm follow up.is there a scematic how to do a pcb?

Question by napoleonis   |  last reply


120v thermostats: need help building or sourcing

I'm planning to build an incubator, and I need something to help regulate the temperature.   I've found some in-line thermostats online, but if I had a parts list, I could easily wire something myself.  Does anyone have any knowledge or experience they can share with me?  Thanks!

Topic by awascholl   |  last reply


How can i recheck my connections?What are the general problems regarding Lcd displays?

I just need to know regarding the buzzer module ...I have been using buzzer instead of  a buzzer module.Is it fine? ..Although it works fine.And please let me know the general troubleshoots related to LCD displays .I think my circuit's working great except for the lcd part. I am done uploading the code.But the LCD doesn't show any temperature values.Please help me

Question by achyuth93   |  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 


constant power with timed output

Hi all,           So ive found a circuit that i wish to use found here: http://www.maplin.co.uk/module.aspx?TabID=1&criteria;=usb&ModuleNo;=220003&C;=SO&U;=Strat15 its a temperature activated circuit so when it gets to say 30 degrees celcius it switches the relay and makes the connection what i need it to do is when it reaches the designated temp, give a momentary 12v for 2 seconds then do nothing for 1 minute, if it is still at the designated temp after 1 minute give another 12v for 2 seconds then nothing for 1 minute and so on and so on untill the temp drops below the designated temp and the circuit will no longer be live untill it reaches temp again. is there any easy way to modify this circuit or another way to do this thanks

Topic by newbie308   |  last reply


Any way to fix a wacky shower?

Once every few weeks, the shower decides to alternate between hot and cold water. When it starts to spray cold water, the water flow is reduced first, then a few seconds later, it turns cold. It goes back warm a few seconds later. This has happened several times in the past month. Any solutions?

Question by DJ Radio   |  last reply


Temperature stabilizer system with peltier battery

Hello everyone! I have a thesis to design a temperature stabilizing(controlling) system for solar cells.I need to use 12V Peltier battery and a simple pc fan.Any further help is appreciated.

Topic by UgurO   |  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



How much temperature do it created by 10w, 20w, 50w laser or laser diod?

I don't know what is laser or laser diod. I want to know about the temperature mainly.

Question by fairuj 



Does anyone have any idea on how hot an average desktop computer gets?

Or do you know how much electricity a normal computer fan uses in a hour? Thanks.

Question by Bostonians   |  last reply


How to create an Adiabatic, Isochloric and Isobaric Environment?

I am trying to make an chamber to examine the growth of a micro organism in the above condition. The chamber temp. should be maintained at 95-100 C and. The environment should be tends to vacuum(Vacuum condition is practically impossible). Please help in choosing the material and conditioning the same.

Question by dashinfoline   |  last reply


vehicle vinyl application

I'm working on a large project with a deadline, and falling temperatures in the Northeast are influencing my work performance. What I need is a portable, efficient, and safe device and/or method that can quickly heat the outside of a car.I am working with temporary adhesive vinyl panels that are being applied to the entire hood and trunk of New York City taxi cabs. We can only apply these panels for about 2 more weeks, and we are trying to cover as many taxis as possible. The weather, however, has been slowing our progress. When the temperature gets to about 60 degrees F and lower, the panels become very brittle, almost like paper, and lose some of their adhesive properties. Application becomes very difficult. We're able to keep the panels in a heated vehicle, which helps a bit. But the outside of the cars, particularly the trunks, are too cold for a proper application. The hood can be easier if the engine has been running for a bit, because this warms the panel and restores its malleability.Does anyone have any suggestions concerning a fast, efficient, portable, and safe method for heating the coachwork of a vehicle? If you can't meet all of the criteria, the device and/or method must at least be portable. But I'm curious to hear any other suggestions, as well. I've come up with a whole slew of ideas that are plenty fast but are in no way safe. Let's face it, though, they're still fun to think about.Any help would be greatly appreciated. I have faith in the creativity of Instructablers! And think of it this way; your help can contribute to a really excellent project. If anyone would like more info, gardenintransit.org. Rock on.

Topic by teej   |  last reply


is it possible to boil water from room temp (20C) using regular batteries?

Hello everyone, is it possible to boil water from room temp (20C) using regular batteries? according to my research, to warm up 500mL of water by 10C within 10 minutes, it will take 1 battery (3.7V 3400mAh). I have a feeling that's wrong but I used this formula and some others: [500 grams * (Tfinal - Tinitial) * 4.186 J/g C ] / [E.battery]

Question by inventor2014   |  last reply


Small Temperature Controlled Relay Circuit? Answered

I'd like to build a small temperature controlled relay circuit. I need to sense water temperature and send +12vdc if temp is <95F and -12vdc if >104F. It's driving a linear actuator so it should advance the rod (+12v) at low (<95F) temperature, hold position (0v) between 95 and 104, and retract the rod (-12v) at high temperature. (>104F) Any circuit suggestions? Thanks.

Question by dmcgraw7   |  last reply


Want advice on a brew temperature controller Answered

Some friends of mine have asked me to make them a brew temperature controller for their microbrewery. I have a rough idea about how I'm thinking of doing it, but would like to check out whether I am on the right track. What they want is something that will maintain a constant temperature inside an insulated box they are building (about 3x1x1m), which the vats will go in to brew. My idea is to use an arduino controller to switch a Solid State Relay and turn the heater on and off to maintain a set temperature. I want to try using low frequency PWM (at about 5Hz) and a proper PI control loop to get really accurate control, rather than just using a standard thermostat action. I'm thinking that given that the relay should switch on every half-cycle (100Hz), this will give me at least 20 levels of control. (Probably more because as the PWM frequency drifts against the mains frequency, the number of on cycles will jump up and down by 1 around an average value.) I decided on this method rather than using a phase angle controller because they are costly and need external components (e.g. a line filter) to work properly. As far as I can see, this switching method should give me pretty good control over the temperature, but it would be good to know if anyone can see any problems with it - I'm designing this more from theory than experience. One thing I'm not sure about is how to measure the temperature. I'm thinking of using an SPI chip rather than try to calibrate a thermistor, but these cost about 4 pounds, so I'm wondering if I could save a bit of money by using a simpler method. Another question is about safety - any advice on things I should do to ensure it's safe would be welcome. I've never done a mains powered project before, so I want to be really careful. I've written up some notes on my proposed design here.

Question by ganglion   |  last reply



Will laminated poster handle extreme temperatures?

Need to know if this poster will last in extrem temperature, if I laminate it (with clear plastic in one of those machines at copy store). Poster will be protected from direct sun and water, but will be subject to winter and summer temperatures in northern Illinois (negative 15 to 105 degrees). Thoughts? Or should I use a glue and no laminate?

Question by Doowhop