Help with ...2 wire multi-tone technique for inductance measurements

[LVocho]

What's the diference between having a DMM to measure resistance and a LCR? I've seen many ATE's with both equipments, a DMM and LCR, the first one it is used to measure resistance (2 or 4 wire method) and the other one it is used to measure inductance or capacitance (always in 4 wire method). Why don't use the same device to do both measurements? Can I use a NI PXI7042 in order to get resistance and inductance from a DUT? Does multi-tone technique eliminates in someway the use of 4-wire method?

 has something to do with the DMM voltage-frecuency delivery capacity?

Any further explanations or comments will be most welcome!

[Dennis_Knutson]

You're more likely to get a response if you post to the Digital Multimeter board for questions about NI DMMs. This board is for the add-in program to Excel called 'Measure' and not for general measurement questions.

Message Edited by Dennis Knutson on 10-03-2007 02:37 PM

[Tania_Lozoya]

Hi LVocho,

You can use the PXI-4072 to measure resistance and inductance of an UUT.

If I am correct, the traditional way to measure inductance and capacitance technique uses a sine wave and a precision synchronous detector.

The PXI-4072 DMM uses a multi-tone signal, basically it generates a very precise square wave (in frequency domain has many frequency contents) and it’s harmonically limited.  You can find more details in the NI Digital Multimeters Help File:

http://digital.ni.com/manuals.nsf/websearch/9D5E03DA68E9F6C9862572C1005B0ABB

And in the Getting Started Guide NI Digital Multimeters:

http://digital.ni.com/manuals.nsf/websearch/E7CCD5EDCF3980C3862572C1005B563F

Also you will find very useful information in this page:

http://zone.ni.com/devzone/cda/tut/p/id/3297

Specifically look at:                         

http://zone.ni.com/devzone/cda/tut/p/id/3078

http://zone.ni.com/devzone/cda/tut/p/id/3713

Please let me know if you need more information.

Tania Lozoya | National Instruments | Mexico