Resistance measurement using PXI DMM 4072 on various frequencies

[Puneet_K]

Hi All,

I have tried to search on various board and unable to find solutions for this. I am trying to measure resistance using NI PXI 4072 on 1Khz frequencey but not luck. When I try using Agilent LCR meter I see correct resistance value.

I have seen few posts on this but didnt get satisfactory solutions.

http://forums.ni.com/t5/Digital-Multimeters-DMMs-and/LCRmeter-Test-frequency-for-Resistance-measurem...

In above post someone mentioned I can use NI DMM 4072 as digitizer, didnot understand much.

Can someone please provide right path to me to fix this issue.

Thanks

[NataliaS]

Hi Puneet_K,

Could you maybe give us schematics of the circuit? How do you connect the NI 4072? What software do you use to read the measurements?

In short you cannot measure the over all impedence of a, for example LCR circuit, NI 4072 measures the compoments of the circuit seperately.

More in the link below:

http://digital.ni.com/public.nsf/allkb/9DADFD5D9B271912862571F6007A8ECC?OpenDocument

Secondly when it comes to DMM, could you elaborate on what part is not clear? I found a few links that can kick you off.

How to create an application with NI DMM:

http://zone.ni.com/reference/en-XX/help/370384T-01/dmm/tutorial/

For the front panel connections of 4072 look here:

http://zone.ni.com/reference/en-XX/help/370384T-01/dmm/4072_front_connector/

Ask away if you have any more questions!

Kind Regards,

-Natalia

Applications Engineer

[Puneet_K]

Hi Natalia,

Thanks for kind reponse, I am doing 4 wire resistance measurement, circuit have resistance,capacitance & inductance. The issue is I want to do resistance measurement on 1KHz and there is no option to change frequency in DMM soft panel for resistance measurement.

I think problem with the type of measurement method used for resistance measurment ( constant current technique).

Please suggest your views.

Thanks

Puneet

[NataliaS · Accepted solution]

Hello Puneet_K,

I have checked the datasheet and the measurement method used described in the specifications of NI 4070/4072 http://www.ni.com/pdf/manuals/371304g.pdf; states that the capacitance is measured using an AC signal, and selects the frequency for testing depending on the range, for instance 3kHz, 1kH, or 91 Hz. The resistance is just measured using a DC signal, and this is often adequate for measuring the internal resistance of a battery. If you need more flexible control for the measurement, you will probably need to have one card as the function generator and then setup a DMM to measure the voltage and another DMM to measure the current, and calculate the impedance from those values.

Hope this helps!

Kind Regards,

-Natalia

[Puneet_K]

Hi Natalia,

Ok thanks I understand it now. I should use another card to do resistance measurement.

Thanks

Puneet