Inalfa Posted April 24, 2006 Share Posted April 24, 2006 I am using the UE9 (with CB37) at the moment to log 5 temperatures, using K-type thermocouples. I need the highest possible resolution (1 degree Celsius), but also I need to measure temperatures below zero. With the range set to a high resolution I can not measure below zero. Is there an alternative way? Is it perhaps possible to set the range to (109), bipolar -0.62V to 0.62V? Kind Regards, Marc Coenen Inalfa Roof Systems Link to comment Share on other sites More sharing options...
LabJack Support Posted April 26, 2006 Share Posted April 26, 2006 The unipolar ranges do go a little below zero, and it is usually enough for many TC applications with negative temperatures. The minimum is usually about -12 mV. Will that work for you? Link to comment Share on other sites More sharing options...
Inalfa Posted April 28, 2006 Author Share Posted April 28, 2006 Thanks for quick responce, I have to measure till -40 degrees Celcius. I set the range to 9 (-0.625V to 0.625V), it seems to work. However I did not calibrate it below zero till now. Do you know if the measurements below zero are reliable? Kind Regards, Marc Coenen. Link to comment Share on other sites More sharing options...
LabJack Support Posted April 28, 2006 Share Posted April 28, 2006 The UE9 does have bipolar ranges with gain (LJ_rgBIP2P5V, LJ_rgBIP1P25V, LJ_rgBIPP625V), but they have not been tested enough to be specified or supported. They are calibrated at the factory, and the low-level functions can use them, but they do not work with the UD driver. The bipolar ranges with gain are likely a little noisier and slower than the normal specified ranges. -40 degrees C is only -1.5 mV of output from a type K thermocouple. You can read that no problem with any of the unipolar ranges such as 0-0.625. The unipolar ranges go to about -12 mV, and the negative limit of a type K thermocouple is -270 degrees C where it outputs only -6.5 mV. Even if the bipolar LJ_rgBIPP625V range is supported, the unipolar LJ_rgUNIP625V range will handle the output of your thermocouple with resolution that is better by a factor of 2. Link to comment Share on other sites More sharing options...
aaaaa Posted April 30, 2006 Share Posted April 30, 2006 Link to comment Share on other sites More sharing options...
PantsOn Posted July 14, 2006 Share Posted July 14, 2006 It will be really appreciated, if there is an example and documentation for DF, VC, VB program with UE9+LJTIA+each type of sensors. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.