Don't you love the big words.... Okay, Lets say I am accredited to generate and measure (for example) 1000 VDC and to measure current to as low as 1 pA (picoamp). But, for example, I am accredited on my CMC to measure up to 2 Giga Ohms.
Even though I am accredited to 2 Giga Ohms, I can put 1000 ACCREDITED Volts across an unknown resistance, and measure the ACCREDITED current to as low as 1 picoamp. This combination theoretically results in 10E15 Ohms (1 Peta Ohm = 1,000 Tera Ohms = 1 Million Giga Ohms). There are of course all of the contributors of repeatability, drift, resolution, uncertainties of calibrations, etc...
So although the cumulative uncertainty of a given established resistance would have lots of contributions, would it nevertheless be accreditable? This, as a derivative measurement to my CMC? Or even if I am able to make the measurement and subsequent derived (possibly) accredited resistance value, would I be limited to CMC, even though my CMC allows me to directly accredit the input parameters (i.e.: voltage source and current measurement).
I could then (if this is accreditable) accredit these values, and make accredited measurements with them which would not exceed my CMC. Or is this the sort of question I should ask my accrediting body?
Even though I am accredited to 2 Giga Ohms, I can put 1000 ACCREDITED Volts across an unknown resistance, and measure the ACCREDITED current to as low as 1 picoamp. This combination theoretically results in 10E15 Ohms (1 Peta Ohm = 1,000 Tera Ohms = 1 Million Giga Ohms). There are of course all of the contributors of repeatability, drift, resolution, uncertainties of calibrations, etc...
So although the cumulative uncertainty of a given established resistance would have lots of contributions, would it nevertheless be accreditable? This, as a derivative measurement to my CMC? Or even if I am able to make the measurement and subsequent derived (possibly) accredited resistance value, would I be limited to CMC, even though my CMC allows me to directly accredit the input parameters (i.e.: voltage source and current measurement).
I could then (if this is accreditable) accredit these values, and make accredited measurements with them which would not exceed my CMC. Or is this the sort of question I should ask my accrediting body?