[volt-nuts] Calibration and Certification - Trust and detail

[Orin Eman]

On Sun, Aug 11, 2013 at 3:36 PM, Orin Eman <orin.eman at gmail.com> wrote:

>
> I should go get the kelvin clips out and compare the 3456A against the
> '61A on some 10k precision wirewound resistors I have.
>


I did.  The resistors are MR102 series 0.01% 1/8W wirewound:

34461A: 10.000 82 +/- 0.000 90
3456A: 10.000 98 +/- 0.000 58

Using 90 day specs for the 61A and 90 day plus 0.0004% per month for the
56A.  Yes, the 3456A resistance specs are better than the shiny new 34461A.

I also compared the DC voltage ranges from 0.1 to 1000V and other than on
the 1KV range, results were within 10ppm.  Still, given the 3456A spec
sheet says add .12(input voltage/1000)^2 % on the 1KV range, I can't
complain; I got 999.984 on the 61A and 1000.062 on the 56A.  I'm pretty
sure that the superscript 2 in the spec meant squared, not that it matters
for 1000/1000.

Now has anyone calibrated a Fluke 343A?  The instructions in the manual are
entertaining.  They tell you to adjust the 1000V range to +/- 1mV, but the
post calibration check says that a freshly calibrated unit should be +/-
100uV at the 1000V setting.

Orin.