×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Continous temperature measurement

Continous temperature measurement

Continous temperature measurement

(OP)
Hi
I need to measure the temperature between 2 ceramic plates (30mm wide, 500mm long) which are in contact. A heat source will pass from one end of the plates to the other and the power to the heat source will be modulated via the temperature measurement device. A pyrometer could be used if we were to use glass as our upper plate. However since the ceramic is not transparent the pyrometer is not an option. The max temperature will be approx 450C.

So what I'm looking for is a thin continuous temperature sensor. Any suggestions greatly appreciated.


Thanks
 

RE: Continous temperature measurement

>temperature between 2 ceramic plates (30mm wide, 500mm long) which are in contact.

'between' means? The temperature differential between the surface of one plate and the surface of the other?

or the temperature of a gap between the plates?

or something else?

>A heat source will pass from one end of the plates to the other.
>the power to the heat source will be modulated via the temperature measurement device.

Controllers modulate.  Measuring devices measure.  Measuring devices can supply an input signal to a controller, which can modulate.  Unless you have some other piece of equipment that is doing something that is inferred by 'modulating', and that would be?  

>A pyrometer could be used if we were to use glass as our upper plate.

What does this theoretical pyrometer see?  What does it focus on?  Are you inferring that you've used a pyrometer to 'see through' glass to another object?

>However since the ceramic is not transparent the pyrometer is not an option.

because . . . .

>The max temperature will be approx 450C.

So what I'm looking for is a thin continuous temperature sensor. Any suggestions greatly appreciated.

RE: Continous temperature measurement

(OP)
Apologies for being a little unclear. I want to measure the temperature of the gap between the plates. Actually there is a third layer of material positioned between the 2 plates and it is the temperature of this material that I need to monitor.

I understand that we need a controller to 'modulate'. We connect a PID controller to the measuring device for this.

Yes, the pyrometer that we have used is designed to see though glass and could therefore be focused on the third layer of material sandwiched between the 2 plates. However, the ceramic is not IR transparent and hence the pyrometer can not see though it.

Hope that makes a bit more sense!

Thanks

RE: Continous temperature measurement

I don't think you need what you think you need.  Why not insert several thermocouples and average them, or control to max reading or whatever suits your objective.  Even if you have an infinite number of meaasurement points, you still have to control to a single finite setpoint.  What will determine the evenness of temperature is how evenly you apply the heat (or remove it).  You will not measure good control into your process.

RE: Continous temperature measurement

Or thin film resistance element embedded in the intervening layer?

JMW
www.ViscoAnalyser.com

 

RE: Continous temperature measurement

Available commercial/standard ranges of bimetallic thermometers are from -80°F to +1000°F.
Bimetallic thermometers are not recommended for continued use above 800°F. The thermal
stability of the bimetallic thermometer is an inherent characteristic of the metals used and
continued operation cannot be assured above 880°F.

RE: Continous temperature measurement

if you want to get fancy...thermal imaging.  I used it on a staged coker in a lab that required tight control.  It exceeded my expectations.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources