NI USB-9211A for Temperature measurement from Thermocoupes

[ronsmagic]

Hi all,

               For our temperature measurement setup we are using typeK thermocouples. To take measurements from these thermocouples i want to use a NI USB-9211A Portable USB-based DAQ. I have an old PC which is integrtaed to our robotic control unit and mustnot for some reason be updated. The specifications of the PC are Windows NT, 32 MB RAM with NI-DAQ version 6.9.1, labview 6.0.1

I want to know whether these specs are sufficient to install the NI USB-9211A and the associatedNI-DAQmx driver software.....I would highly apprecaite any help and feedbacks from your side...

cheers

ron

[ralfn]

Hello ron,

thank you for asking NI.

Unfortunately Windows NT officially doesn't support USB. So there is no NI-USB data-acquisition hardware which runs under Windows NT. 

Alternatively you can take a PCI-card (e. g. a NI PCI-4351 which is designed for very accurate measurements or a E- or M-series-card when accuracy is not an issue). 

The last drivers which work under Windows NT are: 

  - Traditional DAQ (NI-DAQ) 7.3; http://joule.ni.com/nidu/cds/view/p/id/588/lang/de

  - DAQmx 7.5;  http://joule.ni.com/nidu/cds/view/p/id/331/lang/de

But if you look in the readme-file both drivers need at least 64 MB of memory.

And of course the Microsoft-support and our product-support for Windows NT is discontinued. 

I'm sorry, but in my opinion it's not worth the effort.

With best regards,

Ralf N.

Applications Engineer

Germany 

Message Edited by ralfn on 09-16-2008 12:00 PM

[ronsmagic]

Hello Ralf,

                        Many thanks for your reply..I dont think a new PCI card is a solution that we can afford right now since we already have a PCI 6025E installed which is also being used for other I/Os and control purposes. What was intially planned was to connect a SCB-100B terminal block to the DAQ (PCI 6025E) and take measurements from the thermocouples through the Analog Input channels on the DAQ board. But there is a problem..The DAQ board is already connected to a Terminal block which was specially designed for taking measurements from PT 100 temperature sensors.....this leaves us with no connection interface between the PCI 6025 E and the SCB100 terminal block.....this is the reason why i thought a NI 9211 USB could be an easy solution....but as it is clear from your reply it just will not work with our system......can u suggest some other more economical way to take measurements using Thermocouples using our PCI 6025 E DAQ??

i dont know whether i am allowed to say this....but i came across these Monolithic Thermocouple Amplifiers with cold junction compensation from Analog Devices(AD 595)...After going across the details i think that it could be possible to directly connect the Thermocouples to these amplifiers and use the output from the amplifiers as an input to the Analog Inputs on the DAQ board.....do u think it could work??

ill highly appreciate a reply

cheers

ron 

[ralfn]

Hi ron,

you can connect the thermocouple directly to the inputs of the PCI-6025E. Because the output of a thermocouple is very small and is susceptible to noise the result is not very precisely. So it's better to use a signal-conditioning before (amplifier & filter).

At first glance the AD 595 looks like a good solution for this job - if you like some handicrafts. 

With besr regards,

Ralf N.

Applications Engineer

Germany