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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3
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2answers
293 views

Wiring a 2.5km football field with 220v

I have a football field to wire up. It measures 900m x 450m. I need to connect multiple light weight devices that use a 100-220vAc adapter that convert the voltage to 24v for the daughter device. ...
-1
votes
1answer
28 views

liquid insulator by example?

can someone give me some example about liquid insulator .from some text which has been read by me it is just oil can someone told me the other one . it would be good if there is any book reference ...
1
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2answers
66 views

Minimum number of turns on a transformer

I am trying to wind my own transformer for a power supply. How many turns do I need on my primary winding? I know that the turn ratio determines the voltage ratio, but how do I determine the actual ...
2
votes
2answers
60 views

How much is a transformer's secondary floating?

Consider an isolation transformer with its secondary referenced to ground via a resistance R as in the following picture. simulate this circuit – Schematic created using CircuitLab If R ...
0
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0answers
56 views

supplying 240v to a 120v transformer [on hold]

I wanted to know what would happen if we connect a 240v input to a 120v input (steps up 120 to 240)transformer ? Will it get damaged ?
2
votes
2answers
46 views

How to mount a toroidal transformer in a waterproof plastic case

I have a toroidal transformer with mains input and 24V output, which I want to mount in an IP65 ABS plastic case. The transformer comes with two rubber and one metal disc for mounting, along with a ...
0
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1answer
25 views

Flyback Transformer Saturation in Secondary

I am trying to select a flyback transformer for a prototype I'm designing. Almost all flyback transformer data-sheets I've seen provide only the saturation current for the primary winding. The ...
1
vote
2answers
87 views

DO we have to ground transformer?

I am using the transformer (a ballast), and its specfication sheet could be found here ballast specification. But on the data sheet, it doesn't says where we need to ground it. Usually, we would ...
1
vote
2answers
104 views

What do you call a transformer separated from a wall plug?

I got a hold of (from a friend) a AC->DC 5v 2a power transformer - it connects to the wall with lamp cord/ figure-8 connector, and has a USB plug on the other side. I can't for the life of me find ...
0
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0answers
53 views

Reusing a 17kw factory transformer?

I have found some large transformers in a pillaged factory in our town, the biggest one is a 17kw transformer, that isnt labeled clearly so i don't know what it does. I would like to make a 220v-5v ...
1
vote
1answer
79 views

Can I measure inductor current by adding a secondary winding?

I have a buck converter and I want to add a current loop to it. I don't want to use a hall-effect sensor or something expensive like that. I think it is not practical to use a sensing resistor since ...
0
votes
0answers
30 views

Isolated AC mains voltage Measure

I need to measure AC voltage and RMS, but I cant find a good reference. I think that I would need a transformer to step down the voltage, then some kind of amplification to center the AC voltage ...
0
votes
0answers
39 views

Wi-Fi controlled light; 230VAC - 12VDC/3.3VDC

I try to connect an ESP8266-12 and a 12V RGB LED strip to 230V AC. Based on this link, I've came to the following scheme. This will also be the first time I will etch a PCB myself. The partlist will ...
0
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0answers
38 views

Transformer equivalent circuit [duplicate]

If anybody has any experience with practical transformer schematics and analysis techniques, could you please explain how to solve this question, i have looked all over multiple websites and there is ...
2
votes
2answers
64 views

Does adding a capacitor with a transformer makes it a LC filter?

when i add a capacitor with a transformer is a LC filter formed? Moreover if it acts as a LC filter then what inductance to be considered for checking the frequency response of this filter, whether i ...
0
votes
1answer
45 views

Wind high impedance transformer at home

Suppose I need to make transformer at home, but I am unable to wind 100k turns obviously, then can I just connect a resistor in series with a winding to achieve desired impedance? Will it have serious ...
0
votes
0answers
61 views

transformer (no load test)

If anybody has any experience with practical transformer schematics and analysis techniques, could you please explain how to solve this question, i have looked all over multiple websites and there ...
0
votes
0answers
18 views

Hgh frequency transformer with EI core

I want to design a high frequency transformer with ferrite EI core. I have found the area product of the transformer ,but could not find the corresponding E and I values.Please help me in getting the ...
0
votes
1answer
47 views

how to put physics formulae/laws together and make transformer?

i want to make a transformer, i studied all the formulae of physics, for magnetic flux, Emf, mutual inductance, inductance, transformer equations, turn ratios, solenoid etc. but still i can not put ...
0
votes
0answers
24 views

MOT frequency range

I want to use a rewound microwave oven transformer (originally 60hz) to transfer large amounts of AC power. What is the range in frequencies I can use without too much loss (ex. 50 to 70 hz with a 5% ...
0
votes
1answer
53 views

What does the CT (center tap) value mean in a transformer datasheet?

I came across this datasheet, and I am unsure what the CT portion means. The datasheet does say that CT means center tap, but specifically in the image below what does the "10k CT" betweeen primary ...
0
votes
1answer
42 views

Help understanding microcontroller-to-transformer circuit

I have had a hack and understanding how a circuit board works and have hit a snag in understanding one part. The circuit is driven by a microcontroller and has two isolated, biphasic AC outputs. The ...
0
votes
3answers
77 views

How to differentiate center-tapped power transformer from a non center-tapped one?

I'm a hobbyist and I have 2 doubts regarding a power supply described into this schematic: 1) How do I differentiate a center-tapped power transformer from a non center-tapped one? My primary ...
0
votes
4answers
50 views

Using all the taps of the transformer at the same time?

Let me clarify, I have a power transformer with 2x15V secondary (3 secondary terminals). I want to feed a full wave rectifier with 30 V (using the outermost 2 terminals), but at the same time I want ...
0
votes
2answers
54 views

What is a safe and efficient diy or commercial solution to convert 120VAC to 120VDC?

I want to power a series system of ~4 x high power leds, each with a forward voltage of 30-34V. I understand that I can use a diode bridge rectifier to convert AC to DC, but this will have a ...
-1
votes
3answers
34 views

What happens if i kept open the other output terminals of a 3Tap transformer?

I'm having a transformer having 3 pairs of output wires.Out of these 3 pairs I connect my circuit with the first pair of wires and left open all other wires except input.Will it work correctly or ...
0
votes
0answers
24 views

Explain the notification(ECT-PRI-230V)(SEC 12V-3TAP) found on the transformer

I'm having a transformer.I dont know its ratings.It has a sticker showing (ECT-PRI-230V)(SEC 12V-3TAP).What does these notifications mean?
2
votes
2answers
88 views

What is the source of leakage current thru an isolation transformer?

I want to use my oscilloscope to check the cleanliness of the output a high-voltage power supply (electrophoresis type, up to 3000 volts DC). I built a 100:1 voltage divider (out of 2 resistors - ...
0
votes
2answers
84 views

What are the terminals of a 6 wired step down transformer? [closed]

I'm having a Transformer with 2 input wires and 6 output wires(in pair).I dont know it ratings also.Please help me to find what the terminals are?
0
votes
2answers
53 views

DIY Isolated Power Strip?

Would it not be ok / safe to take a surge protector style power strip, cut the mains cable in the middle (or maybe slice it open and just fish out the load and neutral wires so that the ground wire is ...
-1
votes
1answer
68 views

grounding a 220 -> 110 V transformer

i'm in brazil my house has 220V power i have a transformer that converts 220 to 110V it has 2 prong power and 2 prong power out i would like to get the output grounded. I'm hooking up things with 3 ...
1
vote
3answers
267 views

Automatic LED emergency lamp circuit with overcharge protection for 12v lead-acid battery

I am a newbie in the field of electronics.So please help me with my questions. I am trying to implement this circuit below. I have a 9-0-9 centre tapped transformer. Then how to change the circuit ...
0
votes
2answers
115 views

Why does the multimeter need to be set to AC voltage to measure the voltage on secondary winding when driven by a square wave on the primary?

I have a transformer being driven by a square wave at about 9 kHz with a 10/11 duty cycle. In order to measure the voltage on the secondary I have to set my meter to AC. Why is it so? The primary ...
1
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2answers
43 views

Transformers and Short circuit

I want to ask a question about transformers. Primary and secondary parts are isolated electrically and there is only a magnetic coupling. If there is a short circuit in the secondary part, is our ...
0
votes
2answers
112 views

Transformers and phasors question please?

We have the circuit in the figure.I have to find n for which RN has the maximum power.What is the power?We have that J=2A,R1=1 Ohm,R2=75 Ohm,RN=100 Ohm I find the Thevenin equivalent for the left ...
0
votes
0answers
69 views

Multi-winding transformer problem

I am trying to understand the use of the multiple-winding transformer in the above circuit. The input power to the circuit comes from two output terminals of the transformer both of which are at ...
0
votes
1answer
81 views

How to calculate the ratings when a mains-rated transformer is used in a SMPS?

I have a mains-rated transformer that is a leftover part from my previous project. Now since I am experimenting with the idea of SMPS, I am wondering how it would behave when handling the higher ...
0
votes
2answers
111 views

Transformers circuit question,where is my mistake?

We have the circuit in the figure I have to find the power in the resistor 4 Ohm Mesh 1 we have : 16=2I1-8I3+V1 Mesh 2 we have V2=4I2 Mesh 3 we have 0=10I3-2I1 5I3=I1 By the circuit we notice ...
5
votes
4answers
595 views

Does a current transformer produce a proportional voltage or current?

I bought a current transformer which looks like the one below: Datasheet I wrapped the transformer around my 10A kettle, and measured the values using my multimeter. Measuring AC Voltage, I ...
1
vote
0answers
50 views

hijack project microtransformer doesn't work well

I am working on a project that need to get energy harvest from smartphone headset jack.I find hijack project has a solution.the energy harvest circuit of it is below: it use coilcraft transformer ...
0
votes
1answer
54 views

tramsformer input output

I have one machine with transformer from 208 3 phase to 400 3 phase, what will happen if I connect the transformer to 360 V 3 phase as input is it will be okay or not? Because the machine comes from ...
1
vote
0answers
46 views

Wiring diagram and phase number of three phase transformer

Does anybody have an idea how to draw vector diagram of primary and secondary of a three phase transformer? For instance, if I need to draw vector diagram for Yzn5 diagram and then also draw the ...
3
votes
1answer
210 views

Connecting center-tapped transformer to earth ground; or, why am I being electrocuted?

Silly question here. I've wired up a full-wave rectifier using this dual-secondary transformer. If you want to check my wiring, I connected red-to-orange to "create" the center tap (I assume this is ...
0
votes
1answer
44 views

Derive Parameters for Unknown Flyback Transformer

I am designing a 1.7 kV @ 6 mA flyback power supply. The issue I have is that it seems to be extremely difficult to find any type of high voltage flyback transformers for the design. I bought a cheap ...
1
vote
5answers
118 views

Connecting two center-tap transformers for isolation transformer

I need to create an isolation transformer so I can float a Device Under Test (DUT). The parts I have to do so are two transformers: 120V primary / 6.3V-0-6.3V secondary @ 3A. I intend to connect ...
0
votes
2answers
63 views

Full wave AC Voltmeter Vs True Rms Voltmeter

Does a full-wave rectification AC Voltmeter give the same indication as a true rms voltmeter when you measure a 50 Hz sine wave?what happens if the the sine wave is clipped by an inadequate ...
1
vote
1answer
74 views

Why does the volatge drop is huge once a load is connected to a generator?

At no load condition the generated voltage at transformer secondary output is 140 V ac. When a 60W resistive load is connected the voltage drops to 27 V ac. The pmg generator rating is 1 KW 415 V and ...
1
vote
1answer
99 views

Is using a transformer at reduced voltage a bad idea?

My Google is failing me. I want to make an isolated AC voltmeter capable of working at 120 or 240 VAC. I've found a suitable 240 volt to 5 volt transformer to use (current capacity doesn't matter - ...
0
votes
0answers
31 views

Grounding A Circuit of a Power Tool Battery Charger to Use as Car Battery Charger [duplicate]

I took a charger that matches what I need to charge a car battery. The charger uses a transformer and has 3 connections, as does the battery it's intended for (+/-/T). When I plug the + and - alone ...
0
votes
2answers
88 views

Modifying a Simple Transformer Circuit

I have a heavy 14.4V 1.5A heavy battery charger I would like to use to charge my car battery (over time, monitored for heat in a well ventilated area). When I plug the battery to the charger as is, ...