Questions tagged [three-phase]
AC power with three legs run 120 degrees out of phase
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Problem modeling capacitor bank for Three Phase Induction Motor
I'm currently working on a simulation in Simulink and I encountered a problem. I'm using a capacitor bank to improve the voltage drop at the output voltage of the motor. The problem is the capacitor ...
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Current calculation of three-phase system with "extra" resistors
I know you usually say that I should solve it a little bit and then ask for help, but in this question unfortunately I don't know where to start.
This is a question about a three-phase circuit with ...
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Groundwater pump star-delta phase voltage confusion
Last time I got good answers for my question here so I came again today. Thanks. 🙏🙏
The problem am facing today is in star delta starting motor.
When I connect motor to contactor, in phase to ground ...
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Voltage Drop Formula for Three Phase Power Systems
I've just started learning about electricity and power systems, and am currently learning about calculating voltage drop for three phase power systems. The book I am reading is explaining how to ...
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Apparent power for assymetric configurations
I know that the total apparent power S in a 3 phase load for Wye-Wye or D-D configuration = sqrt(3)Vline*Iline.
Is it the same for Wye-D or D-Wye configuration?
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Why is one current reading ~20% higher than the other two in a balanced high-leg delta load?
We are using eGuage watthourmeters to monitor the outdoor unit on five VRF systems powered by two different 3P4W 120/208V high-leg delta panels. The neutral is not connected to the outdoor units.
We ...
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Modeling three phase load for EV charger
When designing a power system to supply EV charging stations, are the stations modeled as delta loads or wye loads? Slightly off topic but is it standard practice to assume that three phase loads are ...
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STM8L ADC multiple channel read Problem
I am using STM8L151Cx with Cosmic C compiler to develop a 3 phase ammeter. I run into an issue during my last stage of development.
3 Phase current is connected to 3 channels in the controller via Op-...
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Relation between line voltage and phase voltage in delta configuration
I have read answers pertaining to this same question, but I could not understanf why the phase voltage is equal to line voltage. This answer says:
In a delta system, the two points required to ...
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How to determine phase sequence of the unbalanced three phase grid?
Let's say I have three phase voltage grid which is unbalanced (three phase utility grid). The phase voltages are sampled by the adc (suppose that the analog channel is properly designed from the hw ...
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What is the relationship between 3 phase motor driving signal and its position encoder?
I have this project to add a magnetic encoder on the motor shaft that will allow speed control by utilizing a TB67B000AHG chip as a driver. I want to install 3 magnetic Hall sensors HW101 stationary ...
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How to decompose the three phase unbalanced grid into the symmetrical components?
Let's I have three phase voltage grid which is unbalanced. The phase voltages are sampled by the adc and I would like to determine in the C language software the positive sequence, negative sequence ...
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Kiln SSR zero-cross frequency
I am planning on using a WATLOW DC2T-24C0-0000 power controller for a three phase electric kiln.
It is a zero-cross 3 phase, 2 leg controlled contactor capable of driving 46 amps with its huge heat ...
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How is the winding cross-induction of a 3 phases motor magnetically interact from one winding to the next?
Considering a Squirrel Cage 3 phases motor. A multi-switch receive the 3 lines of the 3Ø power L1 L2 L3 and distribute the voltage to 6 wires. The multi-switch has 3 position, Speed 1 , OFF , Speed 2,...
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Problem with using 8 channel 433mhz 12 v relay module to control an overhead crane [closed]
I have recently tried to retrofit an existing overhead crane with a 8 channel 433mhz 12 v relay module with a receiver and a transmitter I bought online. My existing crane already has a button pendant ...
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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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I need help with PWM filter capacitor current calculation
PWM filter capacitor current calculation.
I am trying to select the capacitor for the PWM filter shown below. That being the case, I need to calculate the total current (fundamental + harmonics) ...
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Calculate power output of 3 phase generator - uneven sine wave
I am using this BLDC motor [https://uav-en.tmotor.com/html/2018/navigato_0402/52.html] as a generator. The device providing the mechanical drive turns the motor about half a turn and not at a linear ...
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A/C generator = RPC?
I need 3ph power to run metalworking machines in my home shop. I've landed on utilizing a rotary phase converter to accomplish this. Some time ago, I took a 10kw 3ph generator on trade for some work....
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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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Are 3P+N circuit breakers designed to make neutral first and break neutral last?
Consider a CEE 60309 connector, 3P + N + PE. The pins have equal length, but the conductive sleeve matching up with the pins dont have the same length; and of particular interest is that the neutral ...
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Need help with simulation of three-phase active rectifier on LTSPICE
I have already successfully simulated a three-phase rectifier on simulink. However, I wish to implement the same on LTspice because I would have liked to see the effect of using non-ideal components. ...
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Question regarding connecting LISN to a three phase PFC
I am trying to connect a Line Impedance Stabilisation Network (LISN) to a three-phase PFC rectifier simulation model as I want to simulate the common-mode and differential mode EMI. Most references on ...
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Rectify 250A using multiple bridge rectifier
Need to rectify 3 phase 120V AC 250A using 3 Phase 200A bridge rectifier.
Details:
Input Voltage: 120V AC 3 Phase
Input Current: 250A
Problem: Only 3 Phase 200A bridge rectifier is available. Is this ...
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Formula for calculating the current in the neutral of an unbalanced 3 phase system
Morning All, my first post here! I am looking at 3 phase calculations and how to find the current in the neutral for an unbalanced 3 phase system. I am aware that it can be drawn out to find the ...
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PQ Theory: Imaginary power from \$\alpha\beta\$ to \$abc\$ coordinates
In "Instantaneous Power Theory and Applications to Power Conditioning" By Akagi, it states the following with regards to PQ Power Theory:
Is that \$\frac{1}{\sqrt3}\$ coefficient actually ...
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Can I drive only one MOSFET/IGBT in a DC chopper circuit using IR2112 driver?
I have a three phase inverter that is driven with 3 IR2112 drivers board and microcontroller.
I want to take advantage of the board and take two wires from these drivers pins to trigger one MOSFET/...
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Balance 3 phase inverter output
I have a 6kw pv solar system with a 3 phase inverter which splits the generated electricity equally across the 3 phases. I can't resell the excess capacity back so I want to make the most use of the ...
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3 phase low voltage signal generator
I want to create my own 3 phase signal. However, instead of it peaking at 230V AC it must peak at 5V AC.
This generator will be used to feed a secondary unit that uses this signal to perform its own ...
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Measuring 3-phase voltage up to 480V using Arduino/ADC
In order to calculate true RMS phase-phase voltage of a 3-phase delta 3-wire industrial utility, I have been using Zettler Magnetics AHI02516 as step-down/isolation transformers, along with some ...
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I need help understanding what the total Impedance in a delta connection is
I'm trying to upskill by teaching myself electrical engineering. I already have a degree in Theoretical physics and Pure mathematics so I don't mind math heavy answers and don't find the math's of the ...
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Three phase AC regulators
Can someone explain how do we end up with those integration intervals in the Three Phase AC regulators?
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Connecting peak voltage, RMS, line-to-line and line-to-neutral
In EU the line-to-neutral voltage from a power outlet which is single phase (if I understand correctly) is 230V RMS and 50Hz. Then the line-to-line voltage (for the three-phase connection coming to ...
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Distorted output waveform and snubber heating in 3level 3 phase inverter
We are working on 3-level 3-phase 400Hz inverter (110Vrms).
The problem is that the output wave still have some harmonics of the switching frequency.
The snubbers are heating up rapidly when connected ...
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What is the phase difference between phases in 3phase system, if system becomes unbalanced
Is the phase difference between the voltage phase 120 degree in an unbalanced system if not what how can we calculate it?
I will try to explain this a litte more clearly.
More specifically in this ...
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220 volt, three phase issue
My company had a machine moved from one facility to another.
The machine was fully operational when it was disconnected. It operates on 220V three phase power.
When powered up at the new facility the ...
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How do I connect a three phase transformer with three center taps?
I have a three phase step down transformer with three center taps like shown below:
How can I connect it to get the 90 V three phase lines or the 45 V three phase lines at a time for circuits that ...
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Instantaneous 3-Phase Power Calculations Without Neutral or Blondel
I was attempting to help out in this question here regarding calculating instantaneous three-phase power values which allows for numerical or real-time calculation of unbalanced and arbitrary loads.
...
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Is there a device to use 3-phase 400 V and convert into 230 V 1-phase?
I only know basics about electrical power and basically don't know anything about converters/inverters/transformers.
My situation is: I have an EV that I can charge only using 1 phase, up to 6.6 kW. ...
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Calculating 3-phase real and apparent power using sampled signals
Using step-down/isolation transformers, I am sampling the phase-to-phase voltages of a 3-phase, 3-wire industrial utility system in the US (208Vrms, 60Hz). Additionally, I am sampling the line ...
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Need help with simulation of three-phase rectifier with hysteresis controller
I am attempting to design a closed loop three-phase rectifier with hysteresis control using MATLAB simulink. The outer loop compares output DC voltage with reference voltage, given to a PI controller ...
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Will the phase shift be mutual if one phase is stepped down through isolated transformer and added to another phase?
i came across this concept of creating phase shift ( lagging and leading conditions) by adding a stepped down line voltage in series with a different phase voltage. I physically verified the concept ...
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Difference in wire gauge for three phase and single phase domestic power supplies
I'm trying to understand why the recommended wire gauge for a domestic supply depends on whether you're getting three phase or single phase power. Specifically I'm talking about when the power rating ...
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Thyristor controlled 3-phase heater control, spiky current
Lets say you have 10 thyristor controlled heaters in a 3-phase system.
The control of these thyristors is sync'd, so the current draw is spiky (all of the heaters draw current from the same phase when ...
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Finding output power of a three-phase inverter from V and I
I have made a simple three-phase inverter in Simulink. I have the output waveforms for the line-voltage and current as shown below, where the voltage is in plot 1 (I have split the waveforms for ...
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Converting Hall-effect sensor data to encoder data
I want to design a sensored BLDC motor controller, but I have a question.
How can I convert sensor data from Hall effect to encoder data?
Can I convert Hall effects to encoder data correctly when I ...
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neutral to ground voltage in ungrounded Y connection
A 2 MVA transformer 13.8kV Delta / 400V Y ungrounded neutral the voltage at the LV side of the Main circuit breaker terminals between the neutral and ground is 70 Volts, so, the technician isolated ...
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Motor Phase Reverse Direction
We have a mobile belt conveyor driven by a 380V three phase motor.There are two separate lines of conveyors in a conveying system. The mobile conveyor is running in forward direction in one line but ...
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In delta motors, the power factor angle refers to the phase current or line current?
A 600V, 60Hz, ∆-connected, 8-pole synchronous motor has a synchronous reactance of 0.15Ω and armature resistance of 0.02Ω. This motor has an output power rating of 46 hp with a 0.90 lagging power ...
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Pilot light, logic and Opto issues
First time poster, long time lurker.
I’m an electrician to start with, so excuse my lack off EE expertise. Trained in the elevator industry but now float around a few industries.
I’m putting together ...
