[volt-nuts] Traveling Standards

[Charles P. Steinmetz]

Charlie wrote:

>I have some laboratory grade voltage standards here in my home 
>lab.  I have a Fluke 5440B direct voltage calibrator which is 
>cross-checked and compared against a pair of Fluke 732A DC Reference 
>Standards that run on a UPS and are kept hot all the time.  My 
>ultimate transfer uncertainty at 10 volts should be less than +/- 
>6.0 ppm per year and less than +/- 1.5ppm per 90 days over a 
>temperature range of 18 degrees C to 28 degrees C based on the Fluke 
>732A specifications.
>
>The only problem is that I will not ship these units because that is 
>bad for calibration, stability, and uncertainty.  However, something 
>could be arranged if you want to ship the unit to be calibrated to me.

My understanding of Bob's original proposal was that he wants to 
build a stable reference of uncertain voltage, and send that to 
someone (or several someones) who will render an opinion on its 
actual voltage and send it back.  A well-calibrated 5440B and a null 
voltmeter (Fluke 845A/AB/AR, HP419A) would work, as would a 732A or 
equivalent and a precision voltage divider (Fluke 720A or equivalent).

Bob did mention having the recipient power the traveling reference up 
-- if possible, it should be shipped "hot" under battery power so 
there is no power cycle/retrace to worry about.

Best regards,

Charles