Author Topic: Temperature sensor  (Read 4987 times)

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Offline derrick_chiTopic starter

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Temperature sensor
« on: January 07, 2008, 09:06:30 PM »
Can anyone help me out with this, I am looking for a temperature sensor which can take a accurate reading for a nitro big block engine and report back the temperature data in some serial output form, RS232, I2C, PWM or anything of the kind.

Offline ed1380

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Re: Temperature sensor
« Reply #1 on: January 07, 2008, 09:10:42 PM »
what you need to search for is thermistor. its a resistor that changes resistance with temperature. that goes into a mcu that converts the resistance to data and from there you decide what to do with it
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Offline derrick_chiTopic starter

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Re: Temperature sensor
« Reply #2 on: January 07, 2008, 09:13:57 PM »
ahh, ha  OK I'll do a search thanks. ;D All other suggestions are welcome

Offline derrick_chiTopic starter

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Re: Temperature sensor
« Reply #3 on: January 07, 2008, 09:24:01 PM »
Doesn't seem like these sensors have a high enough threshold for the type of application I need them for I need a sensor that can stand temperatures above 250c.  In addition to the fact that I can't seem to locate any.

Offline ed1380

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Re: Temperature sensor
« Reply #4 on: January 07, 2008, 10:08:02 PM »
google high temp thermistor

heres one of teh first things i found.

might have to call them to get a price
http://www.thermometrics.com/assets/images/htp.pdf
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Offline TrickyNekro

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Re: Temperature sensor
« Reply #5 on: January 08, 2008, 12:30:43 PM »
I like thermistors but supposingly the motor won't go higher that 150C, I hope so K type sensors will fit you the best as the have very good response... much greater than a thermistor and if you know a little about microcontrollers you can make it running fo' sure!!!
For whom the interrupts toll...

Offline derrick_chiTopic starter

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Re: Temperature sensor
« Reply #6 on: January 08, 2008, 09:28:56 PM »
K type sensors ?

  OK I'll take a look online for those.

Offline derrick_chiTopic starter

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Re: Temperature sensor
« Reply #7 on: January 08, 2008, 10:17:55 PM »
Can anyone give me some links, of where I can purchase these k type sensor, I can't seem to find any.  Has anyone here used them before, can they interface with an controller?

Offline clone

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Re: Temperature sensor
« Reply #8 on: August 12, 2009, 06:32:39 PM »
thermistors change in resistance with temperature change... whereas j, k, and S type sensors are THERMOCOUPLES and produce a voltage depending on the temperature.

so depending on which you use, you will have to adjust your circuit and code.

here is a good source of info.
http://www.ivaldi.fr/pages_anglaises/capteurtempus.html

Offline wil.hamilton

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Re: Temperature sensor
« Reply #9 on: August 12, 2009, 07:49:35 PM »
http://www.sparkfun.com/commerce/categories.php?c=82

a page with thermistors and k type thermocouple
use the google.  it's your friend.

Offline Soeren

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Re: Temperature sensor
« Reply #10 on: August 13, 2009, 03:30:41 PM »
Hi,

Can anyone help me out with this, I am looking for a temperature sensor which can take a accurate reading for a nitro big block engine and report back the temperature data in some serial output form, RS232, I2C, PWM or anything of the kind.
If this is just for logging, then fine, but if you plan to control  some part of the combustion or supply by this, I'd think twice and then buy a finished solution - well perhaps not, but I get the feeling that the electronics side of such a device might be hard for you (?)
After all, it's a crime to blow a Big-Block any other way than by over-feeding it (which is pretty hard to do ;D)

You could use a thermo couple. The inherent non-linearity can be compensated, but you need to make a cold junction compensation, which is not all that easy around a combustion motor.

I'd recommend a PT100 which will be easier for you to get working (what any pro would choose for this).

Read about both types at: http://www.amra.be/Techinfo.htm.


« Last Edit: August 13, 2009, 03:36:49 PM by Soeren »
Regards,
Søren

A rather fast and fairly heavy robot with quite large wheels needs what? A lot of power?
Please remember...
Engineering is based on numbers - not adjectives

Offline benji

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Re: Temperature sensor
« Reply #11 on: August 15, 2009, 01:39:01 AM »
there are many temp controllers out in the market that provides more than 1 temp monitoring and PID temp control with auto tuning.
they also provide all thermocouple types interfaces and pt100 interface. (like ones from WATLOW)
all of these features are really hard to build in a circuit and takes a long time.

if you just want to monitor then before buying a sensor or a thermocouple check its output voltage/temp response , to be sure if you can interface it to the processor you are using.
good ol' BeNNy

 

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