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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3answers
75 views

What are all the reasons that transformers are considered safer? [duplicate]

I am making a circuit for measuring AC mains voltage and current and I want to avoid using a transformer because it introduces distortions. But everyone says that the circuit will be considered unsafe ...
0
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2answers
70 views

Induced EMF in a transformer

In a transformer a sinusoidally varying voltage is applied to the primary coil of the transformer which give rise to a time varying flux which induce another sinusoidally varying EMF in the primary ...
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0answers
36 views

Need help reverse engineering a combined current-voltage feed power supply for an ion beam source [closed]

I'm currently trying to reverse-engineer (or at least make sense) of the arrangement of electronics i utilize on a FIB ion source in the lab i work in. The staff scientist who constructed it left 2 ...
2
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2answers
66 views

What physical construction features in a transformer control the dot polarity?

As we know, the dot convention is used on transformer symbols to denote whether the transformer "inverts" the signal passing through it or not. However, I am not clear on what in the physical ...
0
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2answers
65 views

Toroidal Core Calculation

Few days ago I got sample of toroidal core from my friend. I don't know any technical details of core just know OD-10cm, ID-6cm, height- 5cm and wet about 1.845 kg(M4 grade CRGO). I want to make ...
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1answer
43 views

Why can I power a 9 volt application on the Collector side of a transistor, and not the Emitter if Base gets 5 volts.

I have a 9 volt application that I want to trigger using an Arduino and an NPN transistor. The Arduino can supply 5 volts to the base. I tried to place the application on the Emitter side of the ...
-1
votes
1answer
65 views

120v power supply section 220v adaptation

I'm building a very simple tube overdrive, power supply section of the schematic can be seen above. as you can see the circuit has been designed for 120v. I will be dealing with 220v instead of 120v, ...
1
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1answer
42 views

Understanding transformer datasheet

Preamble I need an small isolation transformer for 0-6V 400Hz AC (this is my external signal, amplitude is the value): I should get <10mA load from the primary signal source, and in the same ...
2
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1answer
44 views

Is this pulse transformer in saturation?

I have the following schematic: RB3 is connected to PIC microcontroller digital output. I am wondering is it possible to know from the output voltage waveform is this pulse transformer in ...
5
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2answers
92 views

When to “wind-your-own” vs “scavenge” a transformer?

I often see answers for one-off designs including the advice, "Just wind a transformer...." Like it's no big deal. Did I miss a class in which they handed out a sheet listing the formulas for core ...
1
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1answer
53 views

Connecting Transformer to Ethernet PHY

I have Ethernet PHY from Marvell (88E1111-B2-BAB1I000) and Ethernet transformer (S558-5999-AT-F). By mistake the MDI P&N connection got interchanged on the transformer side. Will it work?
1
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2answers
29 views

Relay sequencing: Inhibit state change of one relay if the other is on

I'm trying to find a way to have one relay lock its state if the other is on. Example, 2 relays total: If relay 1 is on then relay 2 can't change state, either turn on or off. Meaning if relay 2 is ...
1
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0answers
35 views

Open Delta's “virtual” power factor

Open Delta yields 57% of power instead of the 86% it would yield if no 30-degree angle gets in the way. Can that 30-degree angle be corrected with a capacitor and an inductor (it requires a cap in one ...
3
votes
4answers
249 views

Why is stepping up voltage during transmission considers I^2*R but not 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*V, increasing V reduces I ...
0
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2answers
60 views

Currents around transformer

If I use a transformer to step the voltage down from 220V to around ~30V and I expect the 30V end to draw up to ~30A, what kind of current magnitude will I have to plan for or expect to see on the ...
1
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1answer
30 views

Multiple output flyback converter simulation in Advanced Design System

I am trying to simulate with Advanced Design System (ADS) a multiple output (one primary winding, three secondary windings) flyback converter (see the image). But I cannot find a component in ADS ...
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3answers
106 views

How to design an air core transformer to operate in audio frequency range (20 Hz to 20 kHz) [closed]

Impedance matching has become a very annoying problem for me in my project of designing an audio amplifier. Here in my locality, audio frequency transformers are not available. I've browsed for ...
2
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4answers
986 views

What does “600 : 600 Ω” mean for an audio transformer?

I found audio transformers online having the following specification: 600 : 600 ohms. My question is what does it mean? Does it mean that it is simply an isolation transformer? Or is it in some way ...
0
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1answer
40 views

Can an ordinary transformer be used for coupling the speaker with a transistor amplifier

Audio transformers are not available in my locality. However, I have bought an ordinary transformer. It has the following specifications: Primary voltage: 230 V Secondary voltage: 6 V Current rating: ...
0
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2answers
46 views

Long term effects of operating in Saturation mode of transformer

What are the long term effects of operating a transformer in Saturation mode? Let's say my transformer can deliver 1VA of power while operating in saturation mode and i consume around 0.6-0.7 VA. ...
0
votes
3answers
58 views

DC voltage measured on an AC to AC wall wart - why and how?

I have a wall wart that says it is Input 110/230V AC and Output 3.5V AC. I put voltmeter on it without switching it from DC to AC (forgot to) and measured 8V DC. I have Googled the subject generally ...
0
votes
1answer
48 views

Modifying switching power supply to produce any voltage(s)

I have few units of 24V 3A output smps power bricks. I'm planning to mod one of this to generate 12V at least at 5A for my LED strips. My idea is to tap two wires from the secondary winding of the ...
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2answers
29 views

lighting halogen 110VAC transformers to 12 VAC, 150W

I have lighting fixture that has two lighting halogen transformers 110VAC, 60Hz to 12VAC and 150W each in something like circular box. Their inputs are connected in parallel. Their outputs are 12VAC, ...
12
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2answers
863 views

If I used the primary coil as an inductor, does the secondary coil affect it?

I've read this question. It's about how to obtain the maximum inductance from a transformer: How do I use a transformer as an inductor? Now, I would like to use the primary coil only as an inductor ...
2
votes
3answers
152 views

low frequency 1-10Hz transformer

I have a 20V, 2 Amp Max, 10Hz sine wave generator, I would like to be able to connect a transformer to step up and down the voltage. How would I go about finding a transformer that I could connect to ...
0
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2answers
56 views

Dual output with Center Tap transformer

I have a transformer with dual input 115v and dual output 9v and rating power 1.15va. My goal is to connect it in parallel to produce single input 115v, single output 9v and rating power 2.3va. The ...
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2answers
50 views

Measurement of power dissipation in a resistance

In the above figure (step up transformer), We can calculate \$V_s\$ using \$\frac{V_s}{V_p}=\frac{N_s}{N_p}\$ and \$V_s=50 V\$ So, power dissipated in the resistance, \$P=\frac{V_s^2}{R}=2500 W\$ (...
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1answer
32 views

Measuring RF voltage transformed by a toroid

This evening I attempted to measure the voltage off of a transformer used for detecting RF currents. This transformer was implemented as a single turn of conductor, through the center of a toroid ...
1
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3answers
99 views

How to measure high-voltage and high-frequency ripple?

I have a ferrite transformer outputting 1.2kV RMS on it's secondary. I have added a diode to do half-wave rectification, and have added a sufficient capacitor (10nF) in parallel to deal with ripple. ...
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2answers
34 views

Secondary voltage with parallel, mismatched transformers

The thought came into my head, what if you had 2 transformers say they're both line level primaries and the secondaries are 6V @ 1A and 12V @ 1A. If you connect the secondaries in parallel, what is ...
0
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4answers
91 views

A question about a step-down transformer with its secondary winding shorted

Above is a transformer with its primary and secondary windings. I just wrote my understanding about a transformer very shorty before my question: Neglecting losses, we can write the voltage and power ...
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1answer
47 views

Strange behavior on transformer driver

I'm trying to make a circuit to drive a transformer from a PWM signal produced by an AVR MCU. Here's the schematic: The MCU output in fact has 2 complimentary PWMs feeding two transistor pairs. For ...
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1answer
34 views

Signal Transformer Characterization for SPICE

I would like to capture the dynamics of a signal transformer (make a good model of it for spice) . I can characterize the transformer as a band pass filter with a gain, or use the built in ...
0
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2answers
66 views

Transformer tolerances?

How much can a transformer go without a failure? For example, let's say that a transformer is designed to work with 500mA. (obviously you should avoid exceeding this limit) But as I learned with ...
4
votes
2answers
105 views

How to properly wind a high frequency / high voltage transformer?

Please, is there any practical tip / caveat I should be aware, when winding a high-frequency transformer? I'm used to wind 50/60Hz transformers and they do work ok, but now I'm trying to make a high ...
8
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4answers
276 views

What is a flyback?

Trying to find this answer is so difficult that I can't even tell whether What is the difference between a transformer and a coupled inductor? is asking the same thing. Some reading suggests that a "...
0
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1answer
69 views

Magnets in Transformers Desgin

What is the advantages, and disadvantages of using neodymium magnets instead of ferrite cores in transformers? How would the magnetic flux density vary of such a transformer utilizing a neodymium ...
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1answer
72 views

Coil Gun Schematic [closed]

I have a question. I have been looking at making a Coil gun lately and i had an idea for a simple one. Just need to know if it would work. Basically: Battery-->Switch-->Diode-->Transformer-->Coil For ...
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1answer
67 views

6 wire transformer

I have a transformer that is rather unusual. My issue is I have no Idea what wire does what. It is a 6 wire transformer. On one side we have one white and one back. On the other side we have one white,...
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2answers
48 views

Identifying a transformer [closed]

I bought an electroplasma lamp from Lave the original, and the lamp is basically a plasma globe. I took out the circuit within the lamp, and it had a transformer with a sticker FB-DY-200B CB, is that ...
3
votes
3answers
139 views

Powering a microcontroller inductively from mains wire

I am in the process of making a mains power monitor using a SCT-013-000 CT clamp and an arduino mini, running on batteries. Even though I should be able to get many months of operation from two small ...
0
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0answers
32 views

Primary and secondary winding ground of transformer short circuited

I am using a 1:2 step up transformer in my circuit i.e. Dynamic Voltage Restorer. I need to double the voltage at the output from 230V to 460V but don't need any isolation. Can I short circuit the ...
0
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2answers
51 views

Doorbell to buzzer with relay and AC to AC transformer

I have the following buzzer and want to use it with a switch by the door. Would the following configuration let this work or are there crucial parts missing? simulate this circuit – ...
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1answer
39 views

Specifications for a flyback transformer

I'm building an SMPS that takes in 110/220V AC and outputs +/- 3.3V DC. The chosen topology is flyback and as is the case of flyback transformers, I need to get one custom made. I have the Np:Ns and ...
0
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2answers
80 views

Transformer drawing 29x more current than it needs

I have an old transformer (20+ yrs) in a building I manage (GE Model 9T23B3872), it takes 277V 3-phase and converts it to 120V 3-phase. It seems very wasteful. It is drawing a combined 8.7 A @ 277 V ...
2
votes
1answer
62 views

How to select a gate driver transformer

I designed a Half-Bridge power supply using Gate Driver Transformers to drive my two MOSFETs. It's working great, I winded the two transformers around very small toroids with some turns, I didn't ...
0
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0answers
16 views

Estimate realistic parameters of transformer for educational simulation of DC/DC converter

I am trying to simulate a full bridge DC/DC converter with SimPowerSystems for educational purposes using the datasheet of a specific converter as example. For the simulation I need the following ...
0
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2answers
78 views

In a single-phase transformer output, which-wire would be phase, and which-one would be neutral?

In a single-phase transformer input, one wire getting entry as live, another as neutral. But what would be in case of its output? In output, which-wire would be phase, and which-one would be neutral? ...
2
votes
1answer
69 views

Specification of IF transformers

I am trying to understand how radio IF transformers are characterized and specified. In the image above from a Mouser catalog are three different IF transformers with a center frequency of 455 kHz. ...