TEMPERATURE MEASUREMENT

[sudhir258]

I WANTED A CIRCUIT WHICH CAN OBTAIN TWO DIFFERENT TEMPERATURE READINGS & THERE DIFFERENCE OF TEMPERATURE IS CONVERTED INTO CURRENT SO THAT I CAN SWITCH ON/OFF MY LAMPS ETC.

PLEASE ANYONE HAVE A CIRCUIT

 

[pmonon]

use with thermocouples

 

[nomad13]

Your idea is not clear to me but i have done one project using ds18b20 from dallas it is a digital thermometer. I use 16f877 as a microcontroller but u can use 16f84a instead if you are not interested in using lcd display.

The idea is like this, there are three limits the low , high and very high. The first relay turn on if the temperature is below low limit, the second relay turns on of the temperature is above high limit, the third one turns on if the relay is above very high limit. The fourth one turns on if the temperature is below low and turns off if the temperature reached the high limit. The fourth relay can be used for heating or cooling control.

If you're interested please email me at space_abyss@yahoo.com

 

[sudhir258]

THANKS FOR YOUR REPLY, BASICALLY I WANT THE DIFFERENCE OF TWO TEMPERATURE READINGS & WHICH IS CONVERTED INTO CURRENT OR VOLTAGE ,SO THAT MY APPLIANCE WORK ON THE DIFFERENCE OF TWO TEMPERATURE READING.

 

[nomad13]

I don't understand why do you need to convert the difference to voltage or current?

You can connect more than two temperature sensor to MCU but if you want you can use LM35 precision centigrade temperature sensor which has linear output of +10.0 mV/°C scale factor or LM34 linear output of +10.0 mV/°F scale factor.

You can use two sensor then connect it to a differential amplifier.

 

[sheraz_1001]

hi , i want a circuit which controls the speed of very powerd motor, can any body help me out

 

[atmaca]

hi , i want a circuit which controls the speed of very powerd motor, can any body help me out

Open a new subject,

 

[chevymn1964]

Try this **broken link removed**

 

[roykyn]

try this at least you ll get the idea about the circuit design
http://www.discovercircuits.com/list4.htm