Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [uncertainty]

non-negative parameter characterizing the dispersion of the quantity values being attributed to a measurand, based on the information used

The uncertainty of a measurement is the confidence interval in which the measurand (true value) is believed to lie.

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Combine uncertainty of multiple measurement instruments

I'm currently working on a project where I'm trying to figure out if there exists a significant difference between measurement instruments for RF power measurements. I will measure multiple Bluetooth modules TX-power with 4 different…
user294957
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Is the quantization error and random error included in the of-range error for multimeters?

When I am looking at a datasheet for a DMM (Digital Multimeter) to calculate the accuracy of a measurement it specifies two error sources: of-range and of-value (also called of-reading). For example this datasheet for the Keysight 34470A:…
Cerike
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When calculating energy from a pulse measured with an oscilloscope, will the timestep always contribute a relative uncertainty of 1/2?

I am trying to calculate the energy delivered by a short electrical pulse. I am using an oscilloscope to capture the waveform and then exporting it to a CSV file. My scope took measurements at a rate of once every 8 microseconds which means that…
Smitty Flufferson
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How do I determine the actual measurement when the multimeter readings fluctuate?

The specifications of the multi meter state +/- 0.8% + 2. I will take that into consideration when I calculate the tolerance. But when I was recording values from the multimeter, I saw fluctuating values. For example, a value kept fluctuating from…
phys_birthdaycake
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Calculating uncertainty in a current divisor

I had the following exercise to do for college: I designed an analog ammeter exactly like this: simulate this circuit – Schematic created using CircuitLab The idea is to design an ammeter capable to measure up to 1 mA, with the D'Arsonval…
Santiago Tissoni
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When calculating the energy delivered by a pulse in an oscilloscope, what is the uncertainty in the timestep increment?

I am trying to calculate the energy delivered by a short electrical pulse. I am using an oscilloscope to capture the waveform and then exporting it to a CSV file. My scope took measurements at a rate of once every 8 microseconds which means that…
Smitty Flufferson
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Calibrating the current (uA) of a TI by using a 34465A DMM as a std and a suitable load

When calibrating a test instrument (TI) on its current generation using the DMM 34465A as the standard and a suitable load in series, I think the uncertainty budget should not include the accuracy and the certificate uncertainty of the resistive…
Zaf
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Uncertainty of output current in voltage-current converter

I have a problem comprehending some things about uncertainty in electrical measurements. Here is illustrative example from my textbook. We use voltage-current converter for measurement. simulate this circuit – Schematic created using CircuitLab U1…
maranovot
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Am I reading the multimeter uncertainty correctly?

I am using a multimeter that has an uncertainty (from the manual) of 0.5% plus 5 digits in DC voltage measurements, 4V range. I have a reading of 1.6172 V. That means an uncertainty of 0.508 V. Isn't that way too much? Like the true value is between…
Granger Obliviate
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How do I find the accuracy / uncertainty of my force sensor system?

I have built a force sensor using an arduino and a self built force sensitive resistor (FSR.) The sensor system consists of a simple voltage divider, where the voltage across the FSR is measured by an ADC and the Arduino. I'm trying to describe how…
BetweenBeltSizes95
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How are equations (transfer functions) and the uncertainties for sensors found?

Does anyone have a good: book / link / resource which describes from the ground up how to find an equation / transfer function and the accompanying uncertainties for sensors? I am looking for references for my bachelor's thesis and want to…
BetweenBeltSizes95
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How many standard deviations is Sensor / Component Uncertainty (+/- X) given in?

For example a resistor of 1kohm with uncertainty of +/- 1%, does this mean in 68% of cases = 1 standard deviation, the resistance will vary by +/- 1%, or does it mean in 95% of cases = 2 standard deviations or is it in 99% of cases = 3 standard…
BetweenBeltSizes95
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What is 1.5%rdg + 4dgt for 15,23 V?

Where "Rdg"is for reading and "dgt"is for digits. So, 15,23 * 0,015 = 0,22845. Rounding to most significant digit it's 0,2. So is this correct? $$15,23 \pm 0,2$$ Since 4dgt is smaller we ignore it. Or am i doing this wrong? I need to find…
Murad Davudov
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What is the uncertainty of the Analog Discovery oscilloscope?

I'm an electrical engineering student and I have to measure the Slew Rate of an opamp (and most importantly its uncertainty). I created a simple voltage follower circuit and I'm using the Analog Discovery 2 to display the output voltage and to…
John Bardeen
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Is measurement uncertainty 2 times standard deviation or 2 times standard error?

Textbooks and online sources often say the industry standard for uncertainty is given at a confidence interval of 95 %. This means out of 100 measurements, 95 would achieve the specified value and deviate around this value in range of the +/-…
BetweenBeltSizes95
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