Questions tagged [transformer]
A transformer couples two or more AC signals through a magnetic field. Often used as galvanic isolation and to transform one AC voltage to another.
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What is the reason for N going back to the transformer station? Efficiency, practicability?
In the picture below you can see an operation of a transformer station and consumers. So in this case 3A flow back via the PEN to transformer station.
picture 1 - standard operation
In the picture ...
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Is copper loss present in the winding of an autotransformer?
Since the autotransformer transfers power conductively in addition to through its magnetic field, does its winding also cause loss of electric power in the form of copper losses? It seems to me that a ...
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Current in secondary side of step-down welding transformer
I am confused about the use of a step-down transformer in a welding machine. The transformer steps down the voltage, let's say from 220V on the primary to 12V on the secondary. It is said that it ...
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Powering 24 V and 12 V device simultaneously from two 12 V batteries
I have two devices which need to be battery-powered (remote area, no grid power available). One device requires 24 V, the other requires 12 V. Both are very low amperage (~50 mA).
Can I use my two 12 ...
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Designing iron core shell type transformer
I would like to design a iron core transformer of shell-type design. I have experience with electronics, but have never built a transformer before and would like to start simple, but not so simple I ...
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Using AC/DC transformer to step down voltage or as antenna balun [closed]
You can get an AC/DC step-down transformer like this from many electronic items.
There are two things I want to do with it:
Convert 6V or 12V DC to 3V or 4.5V DC, but it's not doing it. With the one ...
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dimmer on input of stepdown transformer for amp regulation?
If have a step-down transformer designed for low voltage high amps, and I put a dimmer on the input will that allow me to lower the output amps? I don't care about voltage as it will be negligible, I'...
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Why stepping up voltage during transmission considers \$I^2 R\$ but not \$\frac{V^2}{R}\$?
During the transmission, the generated electric power is delivered after stepping up to hundreds of thousands or even more voltages by transformers.
In that case since \$P=I\cdot V\$, increasing \$V\$ ...
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How do I modify my flyback transformer to output 5kV?
I was wondering how to modify this circuit to end up with a 5kV power supply. I watched a Video by the Plasma Channel on YouTube on a similar design but it outputs 15-20kV which is too high for my use....
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Reluctance concept
I would like to appeal question, where the correct answer was given as option (B) 'Cross-sectional area.' However, I believe that option (D) 'Permeance' is also inversely proportional to reluctance. ...
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How Should I Model Eddy Currents in a Magnetic Core?
simulate this circuit – Schematic created using CircuitLab
I'm primarily a VHDL and DSP guy, so I apologize in advance if this question is dumb.
I have wire wrapped around a magnetic core. The ...
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accurate method of determining turns ratio of single phase transfomer
In determining the turns ratio of a single phase transfomer ,we are asked to use voltage ratio (Vp,Vs) side by side current ratio(Ip,Is). we open circuited the secondary transformer and put test ...
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Transformer open secondary
In the circuit provided by the link, would having an open secondary coil (not having it connected to any ground) damage the it? The coil is connected to pulsed 240v ac at 50hz. If it is not arcing, (...
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Reducing Isolation Transformer Leakage
I watched this video and wonder if its complete separation of primary and secondary coils is the normal way to wind a low-power isolation transformer (e.g., 60Hz 120V 120VA).
I particularly want low ...
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Transformer voltage step-up and heat
A step-up transformer turns a lower alternating voltage to a higher one, while stepping down the current. This is due to the conservation of energy (energy to into the first coil must equal to the ...
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Ideal Transformer Currents Relationship
I'm currently quite confused with the relationship of the currents for an ideal transformer when it overlaps with multiple mesh currents.
It was defined that for:
$$\frac{\bf I_2}{\bf I_1}=\frac{1}{n}...
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Why is core resistance modeled to be parallel to the primary winding of ideal part of a real transformer?
When a real transformer is modeled to a simpler circuit, it is shown that the core resistance or a resistance model which basically describes eddy current and hysteresis loss is in parallel with the ...
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Does all the current lag the voltage in an inductor or is it only a small component?
the way I understood a basic inductive circuit (voltage source + inductor) is that all the circuit current (Io) lags the voltage by 90 degrees. However, I am following this blog tutorial to refresh ...
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How do steel laminations reduce eddy current losses in a transformer?
All online materials I have read so far state that laminations reduce eddy currents but how is this so? I mean why would currents be smaller this way than having a big block of unlaminated iron core ...
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Designing a power supply circuit for a DC motor speed control circuit
I am designing a a power supply circuit for a DC motor speed control circuit.
I am using Proteus to simulate it but it is not working.
I am using a step down transformer to take 230V to 16V then ...
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Why would an in series-opposition center-tapped transformer not be used to drive a circuit?
I understand that if a center-tapped transformer is connected in series-opposition as in the image below, there would be no voltage across both circuit terminals. But can the individual voltage ...
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Analogue Read in ESP8266 WEMOS D1 MINI is fluctuating
I am trying to read the current consumption of a light bulb (160 W) using a current transformer (5A/5mA) connected to the ESP8266 WEMOS D1 MINI analog pin.
I have put a 240 ohms burden resistor in ...
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Recreating a transformer using gyrators
I have a transformer that I would like to recreate using gyrators. What I know about it:
two coils wrapped around the same core
the resistance and inductance of each coil
the coupling factor
the ...
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Why connecting two secondary windings together in an aiding dot-orientation parallel configuration will result in no output?
I need clarification on what would happen if the transformer is in aiding dot-orientation parallel configuration as shown below.
Would that be the same as connecting two batteries, in parallel, as ...
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Single ended scope probes on equipment under test which ARE on an isolation transformer
I am using my company's new oscilloscope and I don't want to mess it up. I have searched all of the topics, but nothing tells me exactly what I want to know so I thought I would ask in case somebody ...
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Isolated flybacks in series to generate high-voltage [closed]
I'm considering placing isolated flyback converters secondaries in series such as the image below. I want to drive the transformers individually using synced clocks (such each transformer has its own ...
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How to determine whether a transformer is dead
My range hood broke, so I took it apart. I confirmed that 125V is arriving at the control board, which is connected to a fuse which is good, which is connected to a transformer. My voltmeter (AC mode) ...
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Dropping the line voltage on an HH Scott 265A tube amplifier
I have a pair of monoblock tube amplifiers that were designed to run on 117VAC. My wall voltage is about 121-123V.
What is the best way to drop the voltage down to an appropriate level?
Option 1: ...
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Find impedence given per unit value-transformer
I really can't wrap my head around this. Three single phase transformers are connected to create a 3 phase transformer. They all have the same nominal values :
voltage conversion : 1.2kV/120 V (...
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Wurth transformer secondary pins on left and right side of transformer
I am looking to use Wurth Transformer 750310988 and I have noticed its pinout is very bizarre. My application is I want to float the secondary of this transformer up to 500VDC and provide a isolated ...
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How to measure flux in transformer in LTspice?
I wish to check the flux through a transformer core in my LTspice simulation. I have set up a push-pull converter simulation using a transformer with a turns ratio of 1 : 1.1, a supply voltage of 12 V ...
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Problem acquiring B-H curve
I'm trying to acquire the BH curve of a toroidal current transformer in saturation, having the primary and secondary current.
The formulas I am using are:
B = (1/NsS) Integral(Vs(t)dt)
H = (Ip*Np)/l
$...
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Isolation transformers and short circuits
For some quick background and info: I'm a relatively fresh (~2y/ experience) EE in the solar field. I work in the R&D department of my company. My country operates in a 230/400V 50Hz grid.
We are ...
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How to add LED array to 110VAC AC circuit that includes small motor
I'm building a small machine that uses 110 VAC to power a small (14 W) motor. I want to add an LED array that a switch activated by the motor turns on and off. (The motor will also be gearing some ...
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Is there a way to tell if I have MLV or ELV transformers driving my 12V 50W LEDs? [closed]
Is there a way to tell if I have MLV or ELV transformers driving my 12V 50W LEDs?
I want to dim a small row of ceiling downlights with 3-Way Lutron Maestro dimmers. The actual fixture is a Nora NL-301 ...
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Identifying SMPS transformer
I have a SMPS acting weirdly and I believe to be caused by its transformer. I need to find a replacement but I'm having trouble identifying it.
The marking has too lines: 1st containing the VDE logo ...
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Placing a comparator below a transformer
I am working on updating an older flyback design. Part of the update is adding a comparator to control a relay through a MOSFET. It's a quasi-resonant flyback so the operating frequency swings between ...
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I have a problem with capacitor discharge in an ignition circuit CDI
I have a hard time understanding what the problem in this circuit is, can someone help please?
I have a Moped with its capacitor discharge ignition box. It works fine, the spark exist, but I want to ...
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Arc Lighter: Relationship between transformer inductance, oscillating frequency and energy of the spark
I'm building an arc lighter using YouTube videos as a reference.
This circuit from GreatScott worked for me.
I'm now trying to understand the relationship between the transformer inductance and ...
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How to deal with one inductor coupled with two different inductors?
I'm fairly confused on how to deal with this type of a situation. I can easily solve circuits with one simple coupled inductor, but this case is obviously different. The task is to solve for the ...
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Can I convert a step down transformer to step up? [closed]
I have a center tapped stepped down transformer 12-0-12 240 V.
I need to convert it to a step up transformer 12 V to 240 V and I need it to be centre tapped.
I am making an inverter circuit to convert ...
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Flyback Transformer Winding Direction
Looking at the basic Flyback Converter Topology, the coupled inductor polarity should be opposite in order for the circuit to operate properly. However, I am confused on how to implement the correct ...
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1950s Era primary and secondary low voltage intercom system [closed]
I have a 1959 low voltage panel right next to my 120 volt panel in my laundry room.
This panel controlled an Old intercom system as well as the lights for the house.
Inside of the panel there seems to ...
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Why does my flyback transformer simply refuse to work?
I've been trying to create a Kirlian setup like the one in a video by 'The Plasma Channel', and the flyback transformer for the power source just refuses to work.
I have a T1010A transformer, and I'm ...
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Do Kirlian setups work with DC power? [closed]
I have been trying to build a simple Kirlian setup, and I've been trying to make my flyback transformer work, to no avail, so I shifted to use the small black 3.7 V to 400 kV transformers (as they ...
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Galvanic isolation in automotive environment
I am using a linear regulator (MIC29302WU) to power a computer mounted inside my car. There is significant noise being passed along the ground of the regulator to the main computer. I verified this by ...
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Simple forward converter - strange demagnetisation
I am trying to build a simple forward converter. After MOSFET turns off I am demagnetising to 100 µF cap on secondary side. There is about 1 µs core doing nothing and after that demagnetisation starts ...
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What’s the explanation on why the outlets wires are on the same coils?
Working on fixing a once upon a time good soldering station so I thought.
Inside the soldering station there’s two transformers, first one for the soldering iron that has an primary of 115 V and ...
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Is there a specific reason they wired the coils this way? [duplicate]
After dissecting the outlet side of the transformer and started unwinding the coil i realized they basically had 3 transformer in one. What I’m trying to understand is why they have it wired the way ...
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How to tell how much current can pass through a transformer
Transformers have a ratio value. For instance, 10:1 will drop voltage 10 times less but increase amperage 10 times more.
Usually when shopping for transformers I see this voltage values for primary ...
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