### Author Topic: Accuracy calculation  (Read 187 times)

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#### JtroTechAB

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##### Accuracy calculation
« on: September 20, 2019, 11:01:56 am »
Hello,

The Accuracy and Resolution for one of the channels of Rigol DP832 is 0.05%+20mV &  1mV respectively.

So for 10mV reading (set on the supply) what should it show on the display?

I have done half calculation only, i.e 0.05% of 10mV is 0.005mV so the range would be 9.995mV to 10.005mV is it correct?

but for further calculation i am not getting desired result. please explain.

the document which i referred is as below

https://brianhoskins.uk/digital-multimeter-accuracy/

#### RoGeorge

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##### Re: Accuracy calculation
« Reply #1 on: September 20, 2019, 11:37:51 am »
0.05%+20mV for 10mV means 10mV*0.05/100+20mV=20.005mV, so the end result will be

-10.005...+30.005 mV

#### JtroTechAB

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##### Re: Accuracy calculation
« Reply #2 on: September 20, 2019, 11:56:28 am »

In case of multimeter accuracy, they denote like this xx%+-xx digits

so the digit part they add depending on the resolution.

so that concept is still not clear to me whether to add directly or not?

#### RoGeorge

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##### Re: Accuracy calculation
« Reply #3 on: September 20, 2019, 12:48:58 pm »
The explanation was about what you wrote.  You wrote "0.05%+20mV".  If you wanted to say 20 counts, then you should have written "0.05%+20" or "0.05%+20 units" or similar.

If it says 20mV then you add mV, if it says digits, then you add 20 units.  It can be either way, mV or digits, depending on how the producer made the specifications.

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