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Products => Test Equipment => Topic started by: Baltazar on July 17, 2020, 06:11:15 pm

Title: Fluke 8846A error charts
Post by: Baltazar on July 17, 2020, 06:11:15 pm
Today I ordered a Fluke 8846A. I prepared error charts that show abs. error as a function of range & measured value. If anyone is interested, I have similar for GW Instek GDM-8351 too.

One question: What is the maximum count the 8846A can show before switching to higher range? I saw some photos displaying 1.000604V on 1V range. At which point will it switch to 10V range? Once I get this info, I will complete the charts to show the overlap of adjacent ranges.
Title: Re: Fluke 8846A error charts
Post by: commongrounder on July 17, 2020, 07:15:45 pm
I have a Tektronix DMM-4050, which is essentially the same as the 8846A.  It will over-range up to 1.2 volts on the one volt range before up-shifting.  It will down shift when the voltage settles back to 1.1 volts, so there is a bit of hysteresis there. Hope that helps.
Title: Re: Fluke 8846A error charts
Post by: bdunham7 on July 17, 2020, 07:35:21 pm
1.2 million counts, so 20% overrange, but it is twitchy and sensitive to noise.  You'll see the word 'Overload' a lot as it shifts ranges.  If is averaging a noisy signal, it may shift down a range sooner than you'd think and may indicate 'Overload' even at much less than the full 1.2M counts.  By 'error chart' do you mean a compilation of tolerances from the data sheet or from actual measurements of your unit?
Title: Re: Fluke 8846A error charts
Post by: Baltazar on July 17, 2020, 09:22:45 pm
Thanks for the info, commongrounder & bdunham7. I updated the charts, i.e. extended every range by 20%.

@bdunham7: This is a compilation of ± (% measurement + % of range) values from spec.