Is it possible to use NI PCI-4461 to measure temperature from J type thermocouple?

[Ihab]

I have a NI  PCI-4461 card installed in my Desktop, is it possible to use one input for vibration measurement and the second input to measure temperature?

[aeastet]

You need to tell us more about what you have. What outputs you are getting from your systems. I would guess that you only have a thermocouple and you want to hook it to the Daq system and read temperature. It is not that simple. You will have to buy an intemediate signal conditioner to do this. The output from a theromocuple is in mirovolts. This signal is very small. If you buy a signal conditioner then it is amplified and output in a voltage is a specified range (i.e. +/- 5VDC, 4-20ma, 0-10VDC etc...)

You can look at NI for some of these or Analog Devices, Dataforth, Omega or any other company that sells temperature monitoring equipment.

[Ihab]

Yes , I have thermocouple only - J Type. Do you know any commercial signal conditioner to do this?

Thanks

[aeastet]

Yes I gave them to you in the above responce:

Analog Devices - 5B modules

Dataforth - 5B modules

National Instruments - Many different solutions

Omega - Many different solutions

You will need to look up what you need and order it.

[SchamWow]

http://www.ni.com/temperature/ is one example

http://www.omega.com/temperature/z/zsection.asp another one

[Ihab]

Thank you SchamWow for your  reply.

I was told that it is theoretically possible but after doing the following:

1. Provide external voltage amplification to utilize the full range of the ADCs and be able to measure with a higher resolution.
2. Disable Current Excitation from the software to prevent any current from going to the sensor.
3. Since you will only be able to measure voltage (and not temperature), you have to create a conversion from voltage units (V, mV) to temperature units (deg Celsius or deg Fahrenheit) inside the software or using DAQmx Scales.

Number 2,3 are clear, I am looking for a simple circuit for  point number 1 above ("External Voltage Amplification Circuit")

can you or anyone help on this?

[SchamWow]

I'm not sure I understand the question you're asking - what do you mean?

Most of the modules should be able to provie an excitation voltage depending where you're looking - what you will need to do is figure out the range and then from there the specification sheets should specify capable analog output voltages.