Questions tagged [lcr]
The lcr tag has no usage guidance.
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Immo coil - Resistance, Reactance and Impedance - Differences needed
Since I work in an automobile lock manufacturing company, I was measuring the DC resistance of an Immo coil using a multimeter (used in automobiles for security purposes) and found out the value was ...
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Measure Delta wound BLDC motor inductance and resistance
I'm using a VESC motor ESC to drive several different motors. When I connect a new motor, it has the ability to detect the motor parameters, but somehow gets it wrong for some of the larger motors: ...
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What's the best way to measure air-core transformer and variable capacitor using an LCR
In order to create a model I need to measure the capacitance of a variable capacitor and an air-core transformer. This is my first time dealing with old models of capacitors and inductors and I'm ...
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Online motor inductance measurement at different rotor angle
I wanted to measure the inductance of PMSM at different rotor angles. I'm familiar with the offline methods of measuring motor inductance but would like to measure a motor's inductance while it's ...
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How to calculate the natural frequency of a series LC circuit?
The below question is just to exemplify what I mean, I don't need help with this question, but rather the concepts behind it
From the wwikipedia article on natural frequency
I concluded that for an LC ...
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How to read this accuracy chart?
I've never seen a chart like this before. I'm just trying to figure out what the accuracy of this LCR meter (BK891) is between the 10-100 µF region. Why does it look like it's putting capacitance vs ...
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Resonance in a series parallel combination circuit
This lc circuit has capacitors in parallel and series with the inductor. What happens at resonance? Will it be parallel resonance, series resonance or can you have multiple resonances? Is the total ...
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Why is the current flowing 1 s after being disconnected \$\frac{1}{e}\ \mathrm{A}\$ instead of \$1-\frac{1}{e}\ \mathrm{A}\$?
If in the given circuit (L = 100 mH, R = 100 Ω, and E = 100 V), after being in steady state for a long time, A and B are connected, find the current flowing in the circuit after a millisecond.
To do ...
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How to find an equivalent LC circuit from a combination LC circuit [closed]
I have a circuit containing a number of L and C, both in parallel and series.
How can I find the equivalent LC circuit (with a single L and C) for such a circuit?
Kirchhoff or Thevenin can give me the ...
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Inductive or capacitive load?
Here I have a series LCR circuit with resonant frequency greater than 200Hz. Is there a way to know whether this circuit is an inductive or a capacitive load?
Edit: The only additional information we ...
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What does negative capacitance mean?
I see negative capacitance measuring electrolytic capacitor at high frequencies (40kHz). How should I interpret that?
The device is LCR Meter Hantek 1832C. I failed to find anything about that in the ...
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Finding ESR of LCR circuit?
I have an LCR circuit, and I am trying to find the ESR of a capacitor.
I bought a 820uH inductor , and an ultra-low 1000pF capacitor, and a 46.6ohm 1% tolerance resistor.
Below is my circuit with ...
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Two-port network parameter measurement using an LCR meter
I was wondering if it's possible to find the admittance parameters of a pi two-port network experimentally using an LCR meter.
For the network shown below, we have
$$
\begin{bmatrix}
I1\\
I2
\end{...
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Determine inductance of large inductor
I asked a similar question before but i am still struggling with this problem.
I am trying to measure the inductance of a large (34cm diameter) electromagnetic brake.
Important findings to keep in ...
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What is the difference between ESR and DCR?
I am measuring the inductance of a large coil using an LCR meter.
I am using the series equivalent measurement mode at 100 Hz.
Why does the LCR meter show that the ESR is 656 Ohm and why does my ...
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Phase Difference Between dynamic voltage and input current
I have a RLC circuit, and I know if we wish to calculate the phase difference between Voltage and Input current then the formula is
$$ \phi = \tan^{-1} \frac{X_L -X_C}{R} $$
But as we already know, ...
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How to choose the right frequency when measuring coil inductance with LCR meter
I would like to drive a 12V DC hydraulic valve coil using a high side driver (VN7140AJ). The driver datasheet specifies the maximum demagnetization energy (page 24), and I would like to make sure that ...
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Measuring capacitance of Metal-Insulator-Semiconductor (MIS) structure with LCR meter
I can not get my head around what a LCR meter measures. My LCR meter measures my device (MIS) which is displayed as C_p and G_p (other components can be neglected). My LCR meter displays C_p, G_p, the ...
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LCR meter weird datasheet
I have a LCR meter. In the datasheet there is a measurement frequency given for the inductance measurement. But not for the measurement of the capacitance. Is the frequency for the capacitance ...
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LC in parallel with R circuit resonance
I've been doing an experiment which involves measuring the voltage across the capacitor at different driving frequencies.
Consider the circuit below:
A sketch of the experimental curve \$(R_1<R_2&...
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Measure in circuit SMD capacitor using LCR meter
I recently bought an LCR meter BK880.
Is it possible to measure the capacitance of a SMD capacitor in a circuit without removing it?
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640
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Unstable behavior of Dc-Dc converter
I am currently working on a high voltage boost converter based on Dos4Evers 555 timer based one https://www.dos4ever.com/flyback/flyback.html (12v to 140-220V). I am running into an issue with the ...
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Measure universal motor inductance with LCR meter
I'm trying to measure the inductance and equivalent series resistance of an universal motor (from a sewing machine, 120V, 0.8A) with a B&K 879B LCR meter.
The measurements vary widely with the ...
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Will I blow up my LCR Meter?
I have a situation where I need to measure a capacitor connected to a live circuit like the image shows. I'm considering a LCR meter because we also have to measure both capacitance and resistance of ...
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How to read instrument's range graph
I have an Agilent 4980 LCR meter and in its manual it has several graphs indicating the effective measurement ranges for each scale, like the one below:
How to read such a graph to be sure that the ...
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LCR meter defect - preventive actions
I got my hands on a BK880 LCR meter and now it's the second time that I destroyed the device.
It can't hold the measurement voltage - So it always tries to measure with around 0V.
What I am doing ...
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Agilent 4294A Impedance Analyzer: "Bridge Unbalanced" during calibration
I am having problems calibrating my test fixture for the Agilent 4294A Impedance Analyzer. The open measurement always works, but with the short measurement I always get the error message "Bridge ...
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Custom Test Fixture for LCR meter
I've designed and built a custom test fixture (based on Keysight's 16047A) to be able to measure multiple pin capacitors.
When testing it to compare both fixtures (the custom and the original), I ...
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Resonant, autotuned nanopulser
My need is to build (or purchase, if existent) a nanopulser, but not an ordinary one: it has to have some specific characteristics.
The premise is:
I have a device which acts as a variable capacitor ...
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Why does an SMPS use LCR on INPUT?
I have this 5 V output SMPS I bought a while ago. I was wondering why there are LCRs connected to the input of my SMPS. I don't understand why it's there.
BTW, I'm an electrical engineering student, ...
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Phase shift in an LCR circuit
In a capacitive circuit the voltage lags current by 90 degrees. In an inductive circuit voltage leads current by 90 degrees. In a resistive circuit voltage and current are in phase. If we have a ...
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Air-core transformer measurement using LCR meter
Is it possible to measure the magnetizing and leakage inductances of an air-core transformer (coupled coils with no ferrite core) normally using LCR meter? I want to get the values of magnetizing ...
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How possible is producing very high voltage and electric arc by a using this simple setup
I have the basic series RLC circuit in simulation below.
As one can see in SPICE simulation, the output voltage at resonance frequency goes upto 1KV:
Can I really obtain that much voltage as in the ...
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Is it possible to test capacitors on a logic board?
First, I would like to know if it is possible to test a capacitor while it is soldered to a logic board, or does it have to be unsoldered first?
Second, is it possible to do so with a multimeter?
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Conjugate, non-conjugate and single poles in an RLC circuit system
In all the texts I encountered so far, I find the following pole-zero diagram example for an RLC series circuit:
The transfer function for the above circuit can be found as:
H(s) = XC/(R + XL + XC) =...
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LCR circuits with changing input frequencies
simulate this circuit – Schematic created using CircuitLab
Ok, imagine an LCR circuit with a resonant frequency f connected to a signal generator inputting a sine wave. The signal generator ...
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How to measure High-Frequency inductance of inductor using an LCR meter?
I have a High-Frequency inductor available and I want to measure the inductance using the Rohde&Schwarz HM8118 LCR meter. If I change the frequency to 100kHz and voltage level to 1.5V (max) I get ...
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Finding the frequencies for a given phase difference between supply voltage and supply current
I am trying to solve a LCR related exercise, but I ran into a problem.
Here is the exercise task and information:
An alternating current circuit is composed of a 50 Ω resistor, an ideal inductor ...
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LCR circuit with squarewave input: Why does the output take a decreasing amplitude through each cycle?
I understand a square-wave will be made up of a sum of sine waves in the form $$\frac{1}{n}sin(nf_0)$$
So when a squarewave is input to a LCR circut designed to be a bandpass filter, it will ...
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Determining the resonant angular frequency
I am facing trouble with finding out the resonant angular frequency of the above circuit.I know that at resonance impedence of the circuit is minimum.I am new to this topic and I tried to find out the ...
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Using a varactor diode to tune a resonance frequency
I think this is a question is some very elementary circuit design but...
I want to use a varactor diode to tune the resonance frequency of a resonator I have built.
I understand that a varactor is a ...
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DC bias of LCR meter
I need to measure inductors with a small DC bias current. Small is a relative term and here as in won't cause any significant voltage drop in the cables of the LCR meter but enough to put my inductor ...
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