Talk:Four-terminal sensing

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[edit] No longer an orphan article

I have added two links in related articles, so I have removed the {{linkless|September 2006}} tag. DFH 16:45, 1 December 2006 (UTC)

[edit] Rename ?

Anyone else agree that we could well rename this article as Kelvin sensing ? DFH 16:47, 1 December 2006 (UTC)

I'm curious as to why? I am not an expert on this but when the technical manuals that Agilent releases refer to two-, three-, four-terminal sensing when they talk about impedance analyzing. It might just be for simplicity's sake. I had actually never heard of Kelvin sensing until I read it on Wikipedia. -- Bubbachuck 08:08, 7 December 2006 (UTC)
Kelvin sensing is the standard term in the realm of [power] semiconductor testing. DFH 19:31, 7 December 2006 (UTC)
OK, you seem to be more knowledgeable, so if you think its a good name change go ahead. -- Bubbachuck 00:11, 12 December 2006 (UTC)

[edit] Section rescued from resistivity

A writer called Vessels42 went to some trouble to write a new section on this topic in the Resistivity article, so I rescued it in case I decide to merge it in to this article later:

==Four point resistivity measurement==
Schematic of a four-point resistivity measurement.
Schematic of a four-point resistivity measurement.
When the resistivity of a sample is measured by simply attaching two wire leads and passing a current through the sample at a known voltage, one inadvertently measures the resistance of the wire leads. For small resistivity measurements and systems where there is a strong temperature dependence, such as superconductors, the resistance of the wires (known as contact resisitance) can completely dominate the measurement. In this situation it is neccessary to use a four-point resistivity probe.
For this measurement, shown at right, a constant current flows through the sample across leads 1 and 4, with an ammeter in series to measure the current. If the sample has a nonzero resistivity, there will be a voltage drop along the length, including between leads 2 and 3, where a voltmeter has been placed. The resistance of the sample is given by the measured voltage divided by the measured current (Ohm's law). The high impedance of the voltmeter assures that little current flows through wires 2 and 3, and thus the measured resistance is attributed only to the sample between those wires, eliminating contact resistance.

--Heron