Questions tagged [phase]
For questions about AC phases (e.g. three-phase systems) or phase in the context of waves, transfer functions, etc. Consider using in conjunction with related tags such as "three-phase", "transfer-function", etc., as applicable.
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How is phase recovered from wireless signals?
I've wondered for a long time how phase information is captured for wireless signals. It's used in applications like QAM for decoding symbols and radar beam forming to to locate targets, but I've ...
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Circuit or Equipment to delay high speed square clock signal?
Hi I have a ttl clock signal that id like to change the phase of to see if it changes effects the unit under test (not relevant but its a digital transmitter and an automated testing setup) this way I ...
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Can overhead ground wire of major transmission lines prevent induction through solar storms?
As I understand it the overhead ground wire found on major transmission lines is placed there in the event of a lightning strike which prevents a surge in the phase conductors. My question is, could ...
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Compare the phase of the voltages across components of a series RLC circuit
Suppose we have a series RLC circuit with equal impedances connected to a 50Hz 240Vrms AC. We use an oscilloscope to measure and compare the voltages across each component.
1) Are their "VOLTAGES" ...
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How to utilize three-phase electrical in residential garage for antique shop equipment [closed]
I hope this message finds you well. Please explain how to utilize three-phase electrical in residential garage for antique shop equipment. The power company will NOT dig new lines for true 3-phase. ...
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Is it true that frequency deviation over 2*pi is the phase deviation of an FM/PM signal?
for ∆f frequency deviation if for FM only and PM has Phase deviation. and
Kf= ∆f (Hz) of FM? Kf = ∆f (rad/s) for PM?
and for th rules:
∆f=(kfmp)/(2p) for FM where mp = mp max-mp min
∆f=(kfmp)/(2p) ...
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Phase shift at very high frequencies
I was given a transfer function:
$$H(s)= \frac{5 \cdot 10^8}{s^2+6\cdot10^4\cdot s+5\cdot10^8}$$
The question I was asked was , what was the phase relationship between input and output voltage at ...
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240 V split-phase to power 12 VDC fans and lights
Im re-powering an model-81 Powermatic bandsaw with a 3 HP Leeson DC motor (14 A max. draw) and a KBCC-255 motor drive (fused @ 15 A). I want to put some fans to cool the DC drive heatsink and LED ...
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How do you calculate the voltage between two phases?
If I have two hot wires at given voltages and phases (for example 120v 0deg and 120v 120deg), how do I calculate the voltage between the two wires?
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Phase lag of an ISO124 isolation amplifier?
I want to use an ISO124 isolation amplifier. The input frequency will be about 100Hz. I'm trying to figure out what the phase delay will be from the input to the output and i'm not having any luck. I ...
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6 phase forked star transformer
I have a problem i'm trying to get to the bottom of. I am basically trying to find the secondary line voltages of a three phase delta primary, with a six phase forked star connected secondary ...
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Staying in Phase On The Grid
I have been an EE for over forty years and never did find out the right answer to this one....
How do power-stations and transformer switching stations ensure that the power they are feeding into the ...
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Capacitive current leads, inductive lags, but how does this translate to voltage on an output?
I'm really confused about the capacitive current leads the voltage, inductive current lags the voltage. The reason for this confusion is the graphs I've seen in different sources trying to explain ...
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Comparator: Noisy sine to square wave, how much phase noise?
In a circuit a comparator is used to convert a sinusoidal signal to a square wave. The input signal however is not a clean sine wave, but has some noise added to it.
The comparator is supposed to be ...
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Phase difference of voltages at one side of a transformer
Consider the circuit in picture
simulate this circuit – Schematic created using CircuitLab
Suppose that I measure VA and VB with respect to GND using an oscilloscope.
Will VA and VB be in ...
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Phase of this AC circuit
What will be the phase of the current trough the coil:
I think that I can find it using:
$$\arg\left(\underline{\text{I}}_\text{L}\right)=\arg\left\{\frac{230\sqrt{2}e^{\frac{\pi\text{j}}{2}}}{\left(...
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Measuring phase difference - LTSPice simulation problem
I'm trying to detect the phase difference between two signals (voltage and current) given from the same source (an ultrasound generator) which works at 20kHz approximately.
I found a circuit that is ...
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Why is the magnitude of the transfer function for my plot showing a band-pass filter, but a strange phase plot?
I am trying to plot a transfer function, and plotting the magnitude appears to show that it is a band-pass filter, which seems reasonable.
The problem is, the phase plot does not match with the ...
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phase matching power supply circuit
I am trying to design an electrical generator that can supply power to my house but without cutting off the utility power supply. The idea is that I could put the generator in parallel with the ...
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Voltage phase delay
Is there a method of delaying the phase of AC voltages? I ask because if I could somehow create a second identical and overlapping sine wave one quarter cycle ahead of the original AC waveform in a ...
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How to plot the phase response of a transfer function
I am trying to plot the phase response of a box with an unknown transfer function by by measuring the phase difference between the input and output at different frequencies but I am not exactly sure ...
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Phase between two sinusoids and which one is leading
that's my first question here.
I'm studying fundamentals of electric ciruits
and I faced this question:
Determine which one leads and by how much:
$$v1(t) = 4*\cos(377t + 10)$$
$$v2(t) = -20*\cos (...
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Confused about phase angle of Network Function
When exactly are we supposed to make our phase angle \$180\$ or \$-180\$. For example if I had the following network function $$H(\omega) = \frac{-\omega_o^2}{\omega^2}$$
Why is the phase angle \$-...
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Phase shifting DC+AC audio signal without affecting its DC content
I have a strongly and asymmetrically clipped audio signal (green signal on attached picture), with DC bias content (blue signal).
In order to obtain the exact DC bias level of this composite signal ...
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BLDC motor phase max current
I run a loaded BLDC motor. Current meter shows 30A. How much current at average will flow through each phase? In BLDC 6-step commutation current flows to a phase and comes out of another, then it ...
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How to find phase angle from transfer function
From the function:
$$H(\omega) = \frac{1}{(1 + j\omega)(1 + j\omega/10)}$$
How is the phase angle obtained when it has multiple poles to get:
$$\phi = -\tan^{-1}(\omega) - \tan^{-1}(\omega/10)$$
...
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Approximation of a Non Ideal Differentiator
simulate this circuit – Schematic created using CircuitLab
The above circuit is a differentiator, the op amp is assumed to be a single pole op amp, that is \$ A=\frac{wt}{s}\$
The transfer ...
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Bode plot: meaning of phase shift
I don't really understand what the phase shift in a bode plot means. Is it the shift of the output compared to the input signal? And how can I intuitively interpret the meaning of the second diagram ...
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Instantaneous phase voltages of 3 phase WYE load
If phase 1 instantaneous voltage is 100 v and decreasing what are the other phase instantaneous voltages if the max voltage of phase 1 is 170 V? Frequency equals 60 HZ. (60 Cps).
I do not understand ...
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determining the start and run capacitors for single phase motor
I have a 5 hp Ajax single phase AC motor. When i got it the start and run caps were missing. Is there anyway to determine the proper start and run cap values based on the info on the nameplate? Thank ...
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Simple mono audio phase inverter
I'm having some bass cancellation problems with my active subwoofer. It doesn't get along with my 2.0 system (different brands).
The subwoofer has a mono line input. I changed the polarity of the ...
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3 Phase Power Question Wording
I am running in to a problem when working on 3 phase problems. I don't really know how to determine if the voltage given in the question statement is the line or phase voltage.
The magnitude of the ...
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High pass filter oscillating
I have created a bandpass filter with an LMC660CN chip, as shown in the image below.
However, in regards to just the high pass filter section, the filter's AC response is set so that at Vout a high ...
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Mach Zehnder phase change?
According to Comsol, a multiphisics simulation software company, a mach zehnder modulator "modulates" the input signal by splitting it into two parallel branches, affecting the relative phase on one ...
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3 phase AC: Can I terminate at main service junction to mitigate line loss? Harmonics?
Suppose I am running very long 3 phase wye distribution from a generator. At the end of my run I will have great line loss and low voltage so i must increase the voltage at the source. This will then ...
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What is a return line in AC power transmission? Why is it needed?
This diagram shows V vs. t for three-phase power transmission:
What is the corresponding I vs. t diagram? Would that diagram help explain what a "return line" is and why it is necessary?
(cf. the ...
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Why 3 phase and not 1 phase power transmission?
Why does power transmission use three lines with three different phases? Why not three lines all in the same phase? Does it have to do with the alternators used for generating the power, or is there ...
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Phase control up to 40A with TRIAC and DIAC (Optocoupler)
I'm projecting a phase control to control the power given to a resistive load of 6 Ohms using a PLC, TRIAC (BTA40-400), DIAC (Optocoupler MOC3023) and a zero crossing detector (4N25).
I've simulated ...
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Is it safe to run a 220v "Split-Phase" piece of equipment on 220v "single-phase"?
EDIT:
Let me re-phrase the question, as I did a terrible job the first time.
I have a mill that can definitely run at 220v, with two legs of 110v, (split phase, as commenters have informed me). I've ...
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Phase shift/angle between input voltage and current rectifier and LC filter [closed]
What is the phase shift approximately between Voltage and current in the attached picture?
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how phase frequency matches in reverse power flow situation
I have a question regarding smart energy systems. Consider a reverse power flow (where the power flows from household to grid) situation, A household has a solar installation and the energy obtained ...
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How to test PLL for step input change in phase
I wrote a simulation for second-order PLL and I would like to test it with an input to see whether my PLL can track the phase. I would like to change the phase of my sinusoidal signal with step with ...
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Phase lock loop frequency of reference signal
I am writing a Matlab code for phase locked loop and up to now I assumed that frequency of input signal is given (known) and I choose frequency of my VCO close or exactly the same as reference signal. ...
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A-C delta-wye phase shift
simulate this circuit – Schematic created using CircuitLab
My question is, because the delta primary in this case is connected A-C, rather than A-B, does this effect the direction of the 30 ...
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Feedback and phase shift on op-amps
I understand that if an op-amp has a phase shift of 180\$^{\circ}\$ and a gain of >1 it will oscillate and I'm trying to get an intuitive feeling for how / why. I've read around a bit, but I don't ...
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Amplitude noise vs Phase noise
I've been reading that Phase Noise dominates in frequencies close to the carrier, while Amplitude Noise is more dominant in higher offsets. Could someone explain this?
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How can I create two ac signals with a voltage controlled phase offset?
Is there a fairly straightforward analog circuit (resistors, capacitors, transistors, etc) to generate two sine waves of the same frequency and introduce a relative phase offset between them? So I'm ...
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Microstepping methods for stepper motors: PWM? Phase? Frequency?
I want to know what methods are used for microstepping stepper motors, and their pro's and cons
For example, I presume, to hold the motor between two steps, PWM would be most efficient; simple ...
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Can I use a Triac dimmer circuit to control the brightness of an AC powered LED light strip? [closed]
I am using this Triac circuit to control the brightness of several incandescent lights. The circuit monitors the phase of the 120 volt wall current, then signals an Arduino when the phase crossed ...
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How do you measure phase difference between two wideband signals
I am receiving a signal from two antennas, and I wish to compare phase in order to extract angle.
I know that you would usually use a phase comparator. I was wondering whether this would work only ...
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