Jump to content

As of July 17, 2015, the LabJack forums here at forums.labjack.com are shut down. New registrations, topics, and replies are disabled. All forums are in a read-only state for archive purposes.

Please visit our current forums at labjack.com/forums to view and make new posts. To post on the current forums, use your labjack.com login account. Your old LabJack forums login credentials have been retired. There are no longer separate logins for labjack.com and LabJack forums.


Photo

Thermocouples +pressure transducers


  • Please log in to reply
3 replies to this topic

#1 Ali

Ali
  • Members
  • 2 posts

Posted 22 September 2014 - 01:46 PM

Hi

I need to measure 19 temperature points with thermocouples type k  ( range measuring is 80-110 C) and measure 5 pressure static points by using pressure transducers output 4-20mA.I ask about the suitable type of LabJack for that  purpose .Thanks.

Ali



#2 LabJack Support

LabJack Support
  • Admin
  • 8677 posts

Posted 22 September 2014 - 02:06 PM

The LabJack T7 and T7-Pro will be the best devices for you and this application.  They have built in cold junction compensation supported at the firmware level and work great with Type K thermocouples.  For measuring 4-20mA signals, check out the Measuring Current (4-20mA) Application Note that we have on our webiste.  An alternative to the T7/T7-Pro that we recommend is the U6/U6-Pro.  The U6/U6-Pro has these features, however you have to do more work on the programming end to work with thermocouples.  It does have a temperature sensor that allows you to perform cold junction compensation, the functionality isn't built into the device firmware.

 

Pro vs non-Pro:

This decision depends on your application and your resolution/speed requirements.  The -Pro gives you a low speed high resolution converter that will give you more accurate readings.  Both the Pro and non-Pro have gain circuitry that will allow you to read both thermocouples and 4-20mA sensors with no issues.  



#3 Ali

Ali
  • Members
  • 2 posts

Posted 23 September 2014 - 03:27 AM

Hi

Thank you for your reply . I have a water flowing inside a pipe with inlet temperature 80 C and change of phase by supplying constant heat flux and is happened at atmospheric condition therefore I want to measure T wall of the pipe ,inlet and outlet temperature of the flowing water .Also I want to measure the static pressure gradient along the pipe .I want type of LabJACK moderate in performance and price .I ll be grateful if you can explain more details about the suitable and if I need use LJ CD or not also LJTick-Current Shunt how many needed .I ask also is pressure transducer need external power supply ? Thank you very much.



#4 LabJack Support

LabJack Support
  • Admin
  • 8677 posts

Posted 24 September 2014 - 07:45 PM

To help you further a list of sensors that you are considering to measure all of your required attributes would be very helpful.  Its hard to help with your project with out that.  Additionally, given that your system sounds quite complex and it seems as though you may switch sensor types a few times before your system gets finalized, a T7 would be your best bet.  It has the most features and flexibility and is by far the easiest to program.  

 

For measuring 4-20mA sensors, the LJTick-CurrentShunt is highly recommended as you won't have to implement any external circuitry.  Each current shunt can measure two 4-20mA sensors.

 

What pressure transducer are you considering? Some do and some don't.  If it requires a stable input voltage somewhere between 0 and 5V you can use the DAC channel on the T7 as your supply voltage.




0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users