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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Transformer Input Wiring Question
I apologize for the basic question, but I just bought a transformer with the following specifications. On the input side, there are two black wires and two red wires. Here is a photo.
And here the ...
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PLL controls frequency or phase?
I have a slight confusion about the working of the PLL. I have been following this document about digital PLL. I want to use PLL to get the same frequency and phase as that of a grid for a grid ...
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My extension show live in all connections when off [closed]
I yesterday bought this new extension and was using for some pi stuff - that's when I noticed small current in pi even though its switch is off.
When I tested it with tester, here's what is happening
(...
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SCR Power Controller (Phase Angle Firing) with Silicon Carbide (SIC) Heating Elements
I’m working with a 3-phase (208V) SCR power controller (Watlow Power Series) operating in Phase Angle Firing mode with current limiting set to 80A. The setup involves two pairs of silicon carbide ...
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Active RF signal repeater
I have two stations, A and B.
Station A broadcasts a pure 10MHz sinusoidal signal on air. A ...
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Need Help with DIY Phase sequence meter
I have seen this video: https://www.youtube.com/watch?v=HyrhW_gnQEM and I am really interested in creating DIY version of this for induction motor. Surfed through internet, but could not anything ...
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I have so many questions about this method of grounding in this video? [closed]
https://www.youtube.com/watch?v=G8JgS-STozA&t=537s
First, I apologize this video is in a different language, but I'll point out what is relevant.
So, in this video. There is a man saying that his ...
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Does the center tap of a single phase distribution transformer get bonded to the grid neutral? [duplicate]
Here are the two wiring diagram.
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Is this how a single phase transformer is connected to multiple houses? [closed]
Single phase transformer serving 3 houses:
I am not sure if this correct. Can someone confirm?
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Why do some op amps' datasheet specify phase margin at open loop?
I am not able to understand what significance phase margin would hold in case of open loop. Shouldn't it be just phase? If it was loop gain I'd understand specifying phase margin to denote stability. ...
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What options are there for multiplying clock pulses by non-harmonic values?
I have a MIDI clock signal which will output pulses at 24ppqn and a device I would like to synchronise which runs at 64ppqn. This is equivalent to a an ⁸⁄₃ clock multiplication.
My current method is ...
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single phase into vfd
I have a three phase in three phase out vfd which is rated for 230V. I would like to use it to power a three phase motor. The manufacturer of the drive states it will run from a single phase input, ...
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Is a high-amp car alternator three phase or single phase power? (12 V, 150 A machine)
I am in mechanical engineering, and have only worked with three-phase power. I modeled a 12V, 150A car alternator as a three-phase electrical machine simply based on when I look up what most ...
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Using a coupled inductor in a multi phase buck converter - how to set the inductor dot notation and converter PWM for best ripple reduction
Based on these Charles Sullivan papers, we can use a coupled inductor in a multi phase converter to reduce inductor ripple current.
https://www.princeton.edu/~minjie/files/sullivan-CICC-2021.pdf
http:/...
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Conceptually, what is phase?
I get it mathematically and how it shows different waveforms in relation to each other on a graph but I am struggling to understand the real world significance and the implications. Like I hear people ...
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Determine AC Motor wiring (again)
I have this air extractor which has an AC motor with multiple speeds.
It has 4 wires (Yellow, Black, Blue, White).
I know for sure that the yellow wire is connected to the LIVE on AC 220V
It has a ...
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Whats the meaning of Im, Is and Ih
I would like to know what's the meaning for the abbreviations of Im, Is and Ih in leakage currents measurements, as it is depicted in these graphis. Could anyone help me?.
The link of the source is: ...
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3 phase motor, star wiring, neutral
Consider a normal 3 phase motor with star/delta, focusing on the star wiring here... what would theoretically happen if I placed a neutral wire from the star connection contactor, to the electrical ...
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How can current phase shift be 90 degrees behind voltage just "inside the capacitor" on an RC series circuit but be in phase in the resistor?
Imagine an AC source in series with an RC circuit.
In this video, the instructor claims current will be 90 degrees behind voltage inside the capacitor but not inside the resistor or the whole circuit. ...
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Phase modulation for binary data - higher frequency harmonics?
I've recently learned about PSK and QAM. I first came across it in this youtube video (timestamped), and my understanding for how it works has remained the same as what is shown in that video. (I also ...
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SCR phase control
I'm making a battery charger with phase control. While making the circuit I had some doubts.
The transformer has a center tap, in this way I can make a full wave rectifier without diodes. Then ...
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TCA785 obsolete, replacement? [closed]
I am looking to redesign an old circuit diagram's phase control IC. I can't find any ICs that can act as a replacement for this item:
TCA785.
What should I look for in an IC for phase control? It is ...
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Which of these connections are incorrect and why? [closed]
Is there a difference in these connections and is there anything wrong on any connection? I am new to phase and neutral wiring. Kindly help me.
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Phase difference between voltage across a capacitor and the source in a low pass filter
Consider I have a low pass filter like that in the figure.
simulate this circuit – Schematic created using CircuitLab
I have considered the voltage source to be \$V\$ and the voltage across the ...
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How can I mathematically show that multiplication of j will cause a phase shift?
I have a simple question that I cannot seem to wrap my head around.
let's say I have a function Asin(wt), if I multiply a '-j' by this function to get:
-jAsin(w*t), I have been told that this is ...
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Why does my neon line tester glow even when I'm not touching its conductive screw?
So I'm testing a phase wire. When I touch the conductive screw top and use the tester like it's supposed to be used, it glows brightly. But when I'm only touching its plastic casing and not touching ...
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1-phase vs 3-phase current calculation
If we have a piece of equipment that comes in two models of power supply connection:
Model A: 208V/20A-1P
Model B: 120V/30A
Measurements of the model gives its max load as 4400W at a p.f. of 0.9.
...
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Using central heating pipe to detect neutral line with a multimeter
I'm exploring the capabilities of my cheap Aneng SZ08 multimiter, which I've recently purchased. I have a question related to the detection of a neutral line in the wall socket using a multimiter. ...
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Behavior of an electric stove on 1-phase vs. 3-phase
I want to replace my current electric stove that's powered by a single phase line with a 20A fuse. I'm in Germany with 230V AC. The overall power that can be delivered is 20A*230V = 4.6kW.
I'm looking ...
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Phase Differences and Wave Equation in ULA Antennas with Far-Field Assumption
I am analyzing a signal received by two antennas, where the second antenna is positioned farther than the first in the direction of wave propagation. I am encountering some confusion when it comes to ...
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Match function generator output phase to line phase
I am new here so my apologies if I am missing pertinent details. I am trying to cancel a 60Hz EM field by sending a small 60Hz AC current through a loop of wire that I am generating with a function ...
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Why does the neon screwdriver (phase meter) light on just by touching the phase wire?
I had a question, can you answer it: as you can see in the picture I uploaded, the single-phase alternating current flows in one wire at one moment and in the next moment from another wire as in the ...
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2 phase to 3 phase
I received a heat tunnel from Asia that has 2 wires. The manual says, "It uses two phase 220V and tri-feet plug with one of it used for the safe wire connecting case and the ground." I have ...
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controlling power by AC frequency
I am working on circuit that will control a heat pad using a triac and microcontroller.
In order to reach minimal EMI noise rather than phase controll I am controlling the frequency.
schema:
As I ...
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Triac Phase angle control Heating method
I purchased a soldering station (Product Link: Tenma 2064549. Just for give more idea. Not for taking about the product.) few years ago and replaced the heating element. After replacing heating ...
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Phase on full wave bridge rectifier
I have a seemingly simple question:
I have a full wave bridge rectifier that is connected to 220 VAC.
When I stick a phase probe on it's (-) negative pole, I see it's light:
And that's something I ...
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How to determine Phase Angle of 16-QAM
I am trying to figure out how the angles for the following input are obtained. For example, why is 0100 -105 degrees and not 45 degrees? Is there a specific method or do we estimate what the angle ...
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Why are the phases of a distorted sine wave always these four values?
In this image I show how I distorted a sine wave with three defects in the transfer function, similar to what you might see in a real transistor or tube circuit. I did the FFT on it and the extracted ...
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Budget friendly battery charger controlled by phase angle ( SCR )
My circuit circuit is below so you can understand what I'm saying.
I want to make a lead battery charger that can control the charging voltage and current (no discharge.) I have a circuit that ...
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Phase velocity expression
We have a \$\beta l\$ expression which is represented as phase velocity.
I know \$\omega_o=2\pi f\$.
What is the exact expression for phase velocity used in here?
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Why does it work to connect between phase and ground, if the electrical circuit is not completed or closed?
Maybe it's a silly question about electrical installations.
I'm not talking about rules, protections or if it is correct to do what I'm going to describe.
I just want to understand why it works.
For ...
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Difference between voltage and phase angle
The voltage at a node can be described by $$ V = |V|e^{j \delta} $$
in which \$\delta\$ is the voltage angle. Voltage angles are required to calculate AC power flows.
The phase angle if often ...
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Stepper motor stepping sequence analysis
I'm currently trying to educate myself on the stepper motor. The figure below is what I am trying to analyze.
First I wanted to analyze the step angle for full step operation and half step. Which I ...
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Why is the voltage distribution a quarter wavelength out of phase with the current in a half-wavelength dipole antenna?
Why is the voltage distribution a quarter wavelength out of phase with the current in a half-wavelength dipole antenna,
as show in this image?
It makes sense that in a graph over time, the voltage at ...
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What is the phase displacement of fault currents on each phase in a symmetrical fault?
In a Line-Line-Line-Ground symmetrical fault, is the fault current on each phase also displaced from each other by 120°?
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ZL30251 phase aligned
I just want to confirm whether the part zl30251 has phase aligned outputs? If not, can it be aligned?
Also, I can confirm that both the outputs are LVCMOS.
Can you please help me with this?
Also, i ...
user220456
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Solid-state analog phase shifter
I have a single A/C source that I would like to phase shift into three different phases, offset by 120 degrees, essentially resulting in something like below:
I've seen folks out in the real world ...
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Air core inductor impedance vs frequency graphs
I wanted an inductor with at least 100 μH, so I used a PVC pipe and some enamelled wire (AWG 21 if I recall correctly) to create an inductor. The inductor does serve its purpose fine as a load ...
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3-phase to single-phase power - motor
I have a circuit with a motor that uses 3 phase power supply.
The circuit includes a control relay (like this ), (L1 L2 L3 NO A1 and T1 T2 T3 - A2) and a thermal relay (like this) the A indicator ...
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Forcing multiple-quadrant TRIAC operation through gate ringing
I got the possibly hare-brained idea to cause a single TRIAC gate pulse to go positive and negative, and thus fire in (maybe not all four but) more quadrants:
ThecLTspice simulation seems to show ...
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