Questions tagged [rms]
Root Mean Square. Mathematical method to calculate effective value from an AC signal.
247 questions
7
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How does this square root circuit work?
I am having a hard time understanding it and I'm planning to use this concept for my true RMS to DC converter.
Here is the source: https://usermanual.wiki/Document/snla140b.1643036625/view
also here (...
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2
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RMS calculation of DC offset sinewave
Look at the following blue waveform and assume for now it is a clean sine wave with maximum 6A and minimum 3.3A. I want to calculate its RMS value.
I performed these calculations:
I used the formula ...
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1
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1
answer
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How do I pick capacitors for high power, high RMS capacitor current Vienna rectifier?
I am designing a Vienna rectifier as a first boost stage in a lead-accid charging station.
The input voltage to the system is 110 V L-L, and peak power is around 18,5 kW.
I have succesfully simulated ...
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-2
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1
answer
83
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AC Voltage measurement for stabilizer
I’m working on a voltage stabilizer project using a Nuvoton MS51FB9AE microcontroller, and I’m confused about how my input voltage measurement circuit handles a range of 240V AC to 300V AC, 50 Hz. The ...
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0
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How to, low cost surface rms measurement of a thin antenna membrane?
My team is working on a project comprising of a thin membrane for antenna application. We wish to measure the surface rms that we have achieved. The requirement is to achieve <2mm rms for which we ...
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2
votes
1
answer
476
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Is there anything like RMS for capacitor or inductor?
In the book "Fundamentals of Electric Circuits" by Alexander and Sadiku the RMS current or voltage is defined as:
So according to this definition RMS is for resistors only.
But in the next ...
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4
answers
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How to find the RMS value of a triangular function (homework)?
I have no idea where I went wrong with this homework question:
The waveform:
I deduced the function as:
$$
y=\begin{cases}
1000t & t\in [ 0,0.002]\\
-1000t+4 & t\in [ 0.002,0.006]\\
1000t-8 &...
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0
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1
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Mean or RMS value of current for filter dimensioning?
I have a power supply which provides rectangular pulse voltage waveform (only positive). The load current is triangular (only positive) it rises more or less linear until it peaks at the end of Ton. ...
-1
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1
answer
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What are the hazards to this DIY RMS circuit?
I want to possilby make a DIY True RMS meter that displays RMS value on an OLED screen. It would plug into a wall and hang from the outlet.
Pretty much the AC goes to a Step-Down Power Module that's ...
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5
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3
answers
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Does the power factor of a three phase full wave rectifier decrease when having a really big inductance in the load?
This is the circuit I am talking about. Now lets take two cases:
One where we have short-circuited the inductor as shown above.
One where the inductor is part of the load and has significant ...
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2
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ACS37800 Voltage and Current Problem
I bought 3 ACS37800 integrated circuits to use in the system. These integrated circuits will measure Voltage and Current for each phase of a 3-phase system. However, while I can measure Current ...
0
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0
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132
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Bode plotter, for audio frequency, using a precision sine generator, a precision RMS-to-DC IC's and a precision difference amplifier IC's
I'm trying to design an audio band bode plotter based on the block diagram of the image below.
The math behind is a subtraction of sine signals. The sine summation in equation 1 can be transformed ...
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0
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51
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Counting RMS value of trapezium shape signal
I have an example here how to count RMS voltage value of trapezium shape signal:
Signal parameters:
H1=11;
L1=9;
C1=0;
tи1=0,15∙T
And given formula:
My question related to RMS formula: we have a sum ...
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3
votes
1
answer
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Flyback output capacitors and extremely high RMS current
I'm designing a DCM flyback converter for the first time and I've encountered a problem where the RMS current through the output capacitors reaches 5.6A. I started looking for suitable capacitors, and ...
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1
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2
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How does a digital multimeter measure?
I have a pulsating signal (always positive) with a frequency of 50 Hz and a true RMS multimeter.
Should I measure the voltage with the multimeter on DC or AC? What´s the multimeter doing in each case?...
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