Questions tagged [calculation]
The calculation tag has no usage guidance.
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What is the current industry practice regarding the impact of current-limiting fuses on arc flash calculations?
Suppose you have a panel. The arc flash incident energy for this panel is computed based largely on the available short-circuit current (SCCA) to the panel, and the protective devices upstream of the ...
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HB100 Doppler sensor calculation
I have a question about the first circuit schematics.
I calculated the second circuit's fcutLow and fcutHigh frequencies like this:
f2CutHigh = 1/(2 * π * 1M * 100p) = 1.6 kHz
f2CutLow = 1/(2 * π * ...
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How to calculate sum of jitter
I have two clock generator and i have connected them in series. If we assume they have jitter of x, what would be sum of jitter how can i calculate that ?
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Calculation of pull-up resistor for open-drain output - multiple loads
Link to voltage supervisor
Link to AND gate
I would like to drive an open-drain output to multiple (5) loads, all of the same type.
I calculated the pull-up resistor range needed and wanted to double ...
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Need help with validation of the design of a capacitance sensor array for soil moisture measurement
Product Description
The device is a soil moisture sensing and analysis device that uses capacitance sensing technology to help manage soil moisture in your garden. One probe set at the bottom of the ...
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How best to perform calculation on voltage and feed output to segmented display?
I'm working on an audio electronics project that uses frequency modulation. A potentiometer will control the tempo/modulation speed, and I'd like to convert the voltage value to a triple-digit value ...
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1
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How to find resistance, inductance, and capacitance of a load/device
I'm planning to make a proper simulation of a circuit. Before the simulation, I need information about the load (resistance, inductance, and capacitance).
Example: the load is a CPU. range of wattage ...
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166
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How to convert cordless tool to corded tool "properly"?
This question is the closest thing that I found similar to my needs, but it is still quite far from the answer I need.
I have 2 cordless power drills, a 12V green Bosch and an 18V DeWalt. Their ...
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Calculation of tolerance of a resistor for voltage sensing
I want to calculate the tolerance of resistor accurately to run a simulation to simulate accuracy of voltage sensor. The resistor I am using is CRCW0603330RFKEA - 330 Ω from Vishay and I can't see ...
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Heating element testing - calculation
I have a 3-phase, 30 kW, 480 V AC heating element.
I’m trying to utilize resistance as an aid for predictive failure.
Using Ohm’s law calculation
480 times 480 equals 230400.
230400 divided by 30000 W ...
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94
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MOSFET thermal calculation
In my application I will use a MOSFET as an on-off switch. There won't be a PWM signal. I want to calculate the temperature rise of the MOSFET but I am confused.
Continuous drain current is 100 A, RDS(...
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151
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How to calculate the maximum current a wire can handle?
Is there a formula for calculating the maximum current a wire can conduct without melting? I found one:
I = αd^(3/2) in which I = fusing current, d = wire diameter in inches, and α = a constant ...
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How to define initial conditions for complex RC circuit?
I need to calculate \$U_2 (t)\$. See the circuit below:
Given \$E\$, \$R_1\$, \$R_2\$, \$C_1\$, \$C_2\$, \$C_3\$.
The first Kirchhoff's rule:
$$
i_1 = i_2 + i_3 = i_4
$$
Now find the all currents:
$$
...
- 159
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Op-amp plus diodes: resistors' values calculation
I am tasked with following: R1, R3 and R3 are to be calculated so that the diodes work in forward bias. Assuming the diodes have a voltage drop of 0.7 V and the op-amp is ideal I have calculated that ...
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Do carbon resistors generate heat in a properly working circuit?
Do resistors in a circuit generate heat based on their resistance value?
Can anybody explain how resistors drop voltage without generating heat?
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Simulate powerbank's disconnected state
There is a powerbank which has (among others) an USB-A port.
The powerbank can be turned on with two methods:
Pushing its button
Connecting a load to either of its ports
In any case, the bank will ...
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What is a "charge cycle" of a lead-acid battery?
I'm trying to develop an algorithm that would roughly estimate the health of a lead-acid battery tied to an inverter backup system.
It seems that my 200 Ah battery pack stays at 100% state of charge (...
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Calculation single phase and three load connected at the same time to three phase network
I have a single phase load (90 A 230 V) and 2 three phase loads (7 kW 400 V 3 phase/9 kW 400 V 3ph+N) connected at the same time to a three phase network.
How the 3 phase calculations (line current of ...
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96
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Frequency of a 555 timer
I want to use a 555 timer (as I have them at hand) to give me a 2MHz clock for an AY-3-8500.
I have two questions really:
While the 555 may not be ideal, is it possible?
How to I calculate the ...
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Getting Discharge Safety from a Battery
I would like to calculate the battery runtime for an ESP32, using a 18650 battery with 2600 mAh (Datasheet).
When I am using a calculator such as this one, it requires me to put in a discharge safety ...
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Rewinding a 6 V DC motor and decreasing inrush current
I have a small simple 6 V DC motor and I would like to rewind its rotor. The motor has 2 magnets. The rotor has 3 poles to wind. Normally each part has 169 turns of winding with 0.15 mm2 copper wire.
...
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219
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Using the superposition principle when there is a current source in the circuit
At the top is the main circuit. Below that is the circuit formed by removing the 5 A current source (We remove that for using the superposition principle and this is the first step).
I don't ...
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Rewriting piecewise voltage function using Heaviside?
Recently I've had an idea to create an assignment where we have low-pass filter connected to the voltage source which is described by piecewise function. I've already dealt with periodic functions ...
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Calculating PID gains analytically on a first order plant (RL Load) - is this possible?
Edit: Just for a bit of context. I have another higher order plant model that has a derivative branch in its control. I thought I'd just implement PID control on the current in an RL load I have just ...
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133
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Calculating steady-state temperature for electrically heated wire
I am working on a program aimed at finding optimal parameters (voltages and feed rates) for a hot wire foam cutter. One starting problem that has to be solved before even attempting to evaluate heat ...
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Filter coefficients and filter calculation methods
I'm trying to figure out the R and C elements for a second-order Bessel filter approximation. Unfortunately, in the below calculations the quality factor is negative, so it is wrong? (I checked by ...
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Calculating hysteresis with an open drain comparator
I have a circuit as follows which will compare an input voltage to a 2.5 V (actually 2.3 V) reference. In one of the documents, it mentions that the feedback resistor must be 100 × Rpullup. If my ...
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How do I calculate the electrical power of a BLDC motor?
I used a current sensor to measure the current of one of the motor phase lines (Iphase or Iline?), and used a voltage sensor to measure the voltage between two motor phase lines (Vline-line).
With ...
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Can the secondary voltage of this old transformer be derived?
Images are of an unknown "4808" PCB-mounted transformer. It has an open 240 VAC primary.
Data: EI48 core, around 12-15VA. The center-tapped secondary is 15Ω-CT-15Ω and 1.6H-CT-1.6H according ...
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Simple circuit of 4.2 V lithium-ion to 3 V use
I have a lithium-ion battery of 4.2 V maximum voltage. I want to power a 1 W LED at 3 V. What size resistor do I need?
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0 dB Bode plot as a reference in an academic paper
I want to compare the calculated bode plot of an inverting op-amp with the simulated one, on the 1 mHz-200 kHz spectrum.
As expected, theoretically there is no stray capacitance on the circuit above, ...
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Why does 277/480V 600A 3 phase = 500 kVA and not 288 kVA?
According to an electrical engineer 277/480 V, 600 A, 3-phase is 500 kVA.
I would like to understand more about why that is. I always thought 277 V x 1.73 = 480 V (and that's where 277/480 label comes ...
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How to calculate RMS noise from datasheet?
I am using an AD9833 DDS as a sine signal source for my circuit. The bandwidth will be 3.5MHz. I would like to calculate the RMS noise of the DDS for my bandwidth. The datasheet has a SNR ...
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Simple question on finding Watts and Wrms
I've done a bit of research but can't find the explanation for this problem, at least mathematically.
I'm calculating W and Wrms of an audio amplifier by knowing output Vpeak and Load resistance. It's ...
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Effective resistance integrator circuit
I've encountered the following circuit and I'm puzzled about the effective resistance that the opamp will see.
I know that R1 is in parallel with R2+R3, so this would be easily answered by R1*(R2+R3)/...
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Crystal oscillator error due to ppm
In this link, the accepted answer states that there may be an error of 1 minute per month if the crystal ppm is 20ppm.
Can someone help me with the math of how the error of 1 minute is arrived?
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CCM Boost PFC avg rms current
I follow the "Fundamentals of Power Electronics-3rd Edition" to derive the below equation.
Now, I would like to derive the Transistor Average,
， and I follow the book formula, but my answer ...
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Pull up / pull down resistor value
Wanting to calculate the value of the pull down resistor for a 555 trigger. For the formula should I use the typical or max trigger current (typ = 0.5 Max = 0.9 μA). I want the calculated value not an ...
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Calculating AC Unit Watts
I'm trying to calculate the watts used from my AC unit. Below I am including my sticker label that's on the AC Unit along with a electrical data sheet I found online for my model.
So far this is ...
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I made a darlington transistor in LTspice. But, that has different values from theoretical values
As you may see from title, I made a darlington transistor like this.
I set each transistor(Q1 and Q2) to have β = 150.
So, total darlington β must have 22500 or thereabouts according to a formula ...
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LM317... Do we need resistors?
In the circuit below, I replaced LM1117 with LM317. Do I need to add resistors at the output terminal? and how can I calculate the output voltage in this case?
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Calculation of capacitor of deep trench DRAM
If I know the depth of the trench L, the size of the DRAM node D and the thickness of oxide (say HfO2) T. How can I calculate the capacitor of a trench?
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How to calculate length needed for heating element (2mm Nickeline/Nichrome wire) to a specified power?
to start off, i dont really understand about electrical engineering. im a mechanical engineering student tasked to continue the project. i dont really understand electrical stuff beside the very basic ...
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How do you calculate electrical active (3-phase) power with L1,L2,L3 (I) angles to L1 (U) and L1,L2,L3 (I) and L1,L2,L3-N (U) measurement?
I get from a Landis+Ggyr E650 electricity meter data via a serial IR head (62056-21 / D0) about every 20s. This meter provides a lot of data, but not the current actual active power (kW).
Some of the ...
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Issues with getting UR
I'm trying to get UR5 from this schema, but something is not right.
All I have so far
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Energy calculation using Arduino
How I can calculate accurate energy if I have power, current and voltage values?
This is the code of energy calculation, the result's it's wrong so how I can fix that?
I want to measure apparent ...
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Calculate power dissipation of split-supply op amp for sinusoidal input
I want to calculate the total supply current and power dissipation of an op amp in a non-inverting voltage follower configuration with a split supply:
simulate this circuit – Schematic created ...
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Flyback converter input current
I have solved A and B of this question but i have no idea how to solve C. any help would be apriciated
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How to get power consumption from datasheet
I am using this stepper motor on my project and am trying to pick a power supply that will be able to supply enough current to all of my components. Looking at the datasheet I'm not sure whether to ...
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Need help on resistor calculation
I'm currently work through an application note from Texas Instruments about building a programmable power supply. The base concept is fine and I understand it, now I'm trying to go through the ...