LabVIEW

cancel
Showing results for 
Search instead for 
Did you mean: 

4 wire RTD Agilent temperature measurement

Hi,

I would like to measure the temperature with 4 wire RTDs with the Agilent 34970A. I configured the EZ Temperature VI with 4 Wire RTD and RTD Type 1 (91). The Problem is, the only data I get are temperatures of 9900000. There is no error message. When I did the set up with thermocouples it worked just fine. When I did the measurements with thermocouples on one card and the RTDs on the second card, the values for the RTDs were the same as for the thermocouples, even if the thermocouples were in a waterbath of 80 °C and the RTDs were outside the bath. I tried to increase the byte count in VISA read (it helped when I had a similar problem with the thermocouples) but it didn't change anything.

At first I would like to calibrate the RTDs alone (to prevent interference with the thermocouples) and afterwards I need to combine the measurements.

Is there anyone who also had this problem and found a solution? I would be very glad if somebody could help me 🙂

0 Kudos
Message 1 of 18
(5,400 Views)
What card are you using? What reading do you get when you manually configure a channel and read the front panel? You should do that before writing any code.
0 Kudos
Message 2 of 18
(5,389 Views)

The card is a Agilent 20 channel multiplexer. The Agilent tells me the right configuration for each channel on the front panel (RTD for the source channels and sense for the other connected channels. when i try to view the measurements on the front panel it says overload 😕

0 Kudos
Message 3 of 18
(5,384 Views)
Then the problem is not with the program. Double check your connections. Refer to the manual. Also the information at http://webpages.sou.edu/~chapman/ch444/intro34970A.htm may help.
0 Kudos
Message 4 of 18
(5,374 Views)

I found the mistake. It was inside the EZ Temperature VI. The interior setting was to read the RTDs with 100 Ohms resistance instead of the needed 1000 Ohms. I was not able to modify this, so I had to built my own VI out of the advanced scan and the configure temperature VI. Now it works 🙂

0 Kudos
Message 5 of 18
(5,211 Views)

can you please send me your written vi...I am also having the same problem and i can't change the default to 1000 ohm for pt1000

0 Kudos
Message 6 of 18
(5,064 Views)

Can someone help me with this isssue? i got the same problem and no solution for it.

I'm using an Agilent 34980a + 34921 Module.

 

I'm using the liabry from keysight. (There's already a module to configure the Chanel and the Resistance R0).

But it don't work.

 

Thanks.

0 Kudos
Message 7 of 18
(4,889 Views)

Now it's working.

 

The standard Modules of Keysight and NI are using the MEAS command. But this deletes the Config which was made before and set the values to the standard.

Im working with the Read Command and it's working fine.

0 Kudos
Message 8 of 18
(4,865 Views)

Ich brauche auch dein VI please, wenn du es noch hat

0 Kudos
Message 9 of 18
(2,664 Views)

Hi,

 

Will try to find it. 

You can use Standard VI from Keysight / Agilent. Then you need to open the Sub Vi and Change MEAS with READ.

That's all.

What LV Version do you need?

0 Kudos
Message 10 of 18
(2,656 Views)