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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Is there a transformer that could replace the component: Conrad Electronics type 516260-62?
I am a doctorate student working on a waveform generator unit similar to the TENS and Microcurrent devices that were discussed in the following forum:
For a nerve-teste circuit, what causes the ...
0
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1answer
88 views
Effect of an isolation transformer on leakage current
How do isolation transformers affect the leakage current through protective earth in a system?
Scenario 1: Mains is directly connected to circuit. Metal enclosure has a protective earth connection ...
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1answer
82 views
How will the output of a 12V transformer wall wart differ from that of a 12V SMPS brick?
I have been working on a project to drive an electric door strike from an Arduino shield of my own design. Actually, I'm using a Freetronics Eleven and not an official Arduino, which is relevant ...
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1answer
47 views
what transformer should i use? [closed]
OK, i am new at all of this and for my first project i desided to try to use the power from a coal (like the ones you sprinkle incense on), use a Peltier to convert the heat to dc, now i know i need ...
1
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1answer
60 views
Live-Neutral transformer fault
In this critique of an ELV PSU design, it is suggested that a "Live-Neutral" fault could result in a fault current of thousands of amps. I'm sceptical. Please could someone explain how this could be? ...
2
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1answer
51 views
How to measure the VA rating of a step down transformer
I have an uncased, unlabeled step-down transformer which converts 240 UK voltage to 112v (I have measured this with a meter). It weighs 1.5kg, is 10 x 8 x 10.5cms including the attached 2-pin US ...
2
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1answer
47 views
Is NRTL approval required for the sub components I purchase and assemble into a final product in order to sell the product in USA?
I manufacture a lighting product made up of components I purchase and then assemble into a housing and heat sinks that my company manufactures. The components I assemble include an electrical driver/ ...
3
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1answer
80 views
How to pick a Push-Pull Transformer?
I have to admit up front this is a borderline shopping question. But the fact is I'm looking at an application note from Linear Technologies. That application note calls for Coiltronics CTX02-14659 ...
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3answers
104 views
transformer for power supply
i bought this transformer to use in a power supply http://www.dhwelectronics.com/Safety_Isolating_019000600020/P028_1A_Secondary_30VA_Transformer_With_15015_Vac_Ouputs/
i want to have two outputs but ...
0
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2answers
42 views
Need some CCFL transformer help
I was wondering about these transformers. It says it requires a DC input (I think) however don't transformers need an AC input, and if so does that mean I would need to make an oscillator circuit to ...
3
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3answers
178 views
Dots in a transformer symbol
I came across this schematic:
What do the dots in the transformer indicate?
5
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3answers
272 views
Ethernet connector and transformers
I'm working on an Ethernet connection for a PIC18F4620 with the ENC28J60. I found a useful article here, with a schematic:
I see I need transformers between the RJ45 connector and the Ethernet ...
3
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3answers
155 views
Building a power supply, want to stay alive
I am building a power supply for a very old laptop. The circuit uses a transformer (220 V primary to 15 V secondary, 33 VA) and that worries me a little. (Please note that I an enthusiast and so far I ...
2
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2answers
139 views
how do they make travel adapters so small?
How do they make cellphone adapters, especially "travel adapters", so small?
I once peeked inside an old Nintendo adapter, and it had (among other circuitry) a rather-bulky step-down transformer to ...
0
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1answer
87 views
Ground Fault Question Regarding a 3 Phase Circuit
I'm needing to design a 3 phase ground fault detection system for a 480V system. It will need to be able to trip when there's ground fault current >1A.
I have done some reading and it sounds like ...
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3answers
84 views
Converting voltage to amperage [closed]
I was wondering if power transformers can be used to convert a high-volt/low-amp AC to low-volt/high-amp AC.
For example:
AC power input (E±=100 I=1) to a transformer primary (100 windings) and ...
0
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1answer
68 views
Getting the right converter for this 110/120v device, where the power is 220/240v
I have an appliance designed for 110/120v. It says it runs peak at 1200 watts, but I can't find yet any mention of Amps. I'll be using it in Europe at 220/240v, if it is possible.
I understand I can ...
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1answer
159 views
Can I pull ampere out of transformer as I want not as my circuit need?
I have transformer with max ampere 20Amp, If I tried to charge 12V battery with it, it gives 2Amp..I want to do something that force transformer to gives 10Amp for example...Is that even possible?
...
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67 views
Is there a phase shift in a single phase transformer and why?
I was wondering why we consider both sides' voltages and currents with the same phase although they cannot be considered in series.
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1answer
126 views
At very high frequency (700 kHz), an AC circuit has a voltage reading 10 times the EMF, why is this?
I've set up an experiment in which I vary the frequency of an electric signal using a waveform generator. The experiment is testing a transformer, but I've encountered a problem on the primary circuit ...
4
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2answers
106 views
How to properly snub transient spikes from a transformer and prevent switch mode power supply burn out
I've received a failed switch-mode DC-DC step down converter (part# LTC3631 from Linear). This circuit was driven by a 24VAC transformer which is rectified on the circuit:
simulate this ...
4
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1answer
73 views
2 full bridge with 2 secondary winding in series… is it possible?
simulate this circuit – Schematic created using CircuitLab
Is this possible? Think of the center tap transformer as a 2 winding connected in series
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93 views
Input and Output terminals of the transformer
I want to use low voltage ac supply for my projects. I have got one from my computer SMPS.
But its winding terminals are making me confuse.At one side,there is 2 terminals(in the picture,it is down ...
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2answers
301 views
how to use CT to measure current [duplicate]
I have purchased CT but don't know what his terminals means and how to identify primary and secondary coils terminals. I am software engineer but currently learning pic controller. as for I have read ...
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1answer
289 views
Current Transformer with pic16f877a
I am currently working with a current transformer (CT) to measure the load current of a system. I am connecting the CT with a pic16f877a microcontroller using a basic circuit I found on the internet. ...
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0answers
169 views
Flyback transformer driven compact fluorescent circuit [closed]
I seem to have run into trouble trying to run a flyback transformer with a CFL circuit.
I connected the high voltage pins of the CFL to the flyback transformers primary input and the other two pins ...
3
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2answers
158 views
Centre tapped secondary winding
In the construction of a full wave rectifier, why is there centre tapped secondary winding in the transformer? OR What's the role of centre-tapped transformer in a full wave rectifier?
5
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2answers
129 views
Are AC adapters electrically isolated?
are the ac adapters e.g. laptop charger ; are they electrically isolated ( from ground ) because they have a transformer . Im asking this because i read that isolated transformers are 1:1 ratio where ...
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2answers
47 views
control transformer
In control transformer ,used in Switchgear i.e. 415V/240V—this transformer is single phase transformer or 2-phase transformer?
As primary is 415 V which is tapped from 2 phase….while secondary is ...
2
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2answers
157 views
Can I charge multiple devices from one transformer?
I am getting tired of bringing 3-4 power cables with me every time I travel and am thinking about building a multi-device power charger. In other words, this charger will have one transformer (and one ...
3
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2answers
86 views
How can I get 17 VDC from 25 VDC with current may up to 10 A?
I'm new in electronic and electrical circuits, so maybe my question will be naive.
I have an electrical transformer that gets 220VAC as an input and gives 25VAC as an output, and can produce 20amp ...
2
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1answer
165 views
advice on a transformer for power-supply
i know this type of question is common and yes i could just buy a known transformer for $10 on ebay or something. either way :)
i am interested in building my own power supply, something variable ...
3
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1answer
435 views
PSpice homework Question
I'm having trouble with this question. Can somebody help?
I know the equation for part a) is:
$$P_{\text{max}} = \frac{1}{4} \cdot \frac{\mid{}V\cdot{}t\cdot{}h\mid{}^2}{R_\text{L}}$$
And I'm ...
5
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1answer
260 views
Hand winding smps transformer
I would like to hand wind a smps transformer for prototyping work. The specs of the transformer are as follows :
Transformer Parameters
Core Material: EE16, NC-2H or equivalent, gapped for ALG of
...
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1answer
123 views
Can I use more diodes to reduce the voltage off a diode bridge?
I have a transformer labeled as providing 9Vac, 3.36 A. It appears to provide 9.4 v ac according to my multimeter.
It runs through a diode bridge (WAB 040 diodes -- already fried the last version), ...
2
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3answers
171 views
How do I test how many amps a transformer actually puts out
I have a 120v <-> 9v ac transformer rated at 3.34 amps, but my multimeter suggests that (after running it through a diode bridge), I can get 7+ amps out of it @ 9.4 volts ac.
Can I?
I have a ...
8
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1answer
136 views
What is a Class 2 Transformer
I need to replace a damaged 120V-12V transformer that is a European sourced Comelit Model 542012/A, also marked as "Class 2 Transformer" supplying power to a halogen table lamp. My question is what is ...
4
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1answer
172 views
how to design a switch which works when an input of 0.10 is applied
i have an alarm clock , it's output voltage to the alarm buzzer is around 0.15 volt ,
i need to attach an electrical appliance to make it operate on scheduled time ,
for that i had used this circuit ...
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3answers
162 views
The type of transformer having 6 output terminal and 2 input terminal, with an insulated conductors projected from its top?
I got a transformer from my system SMPS. I have heard about 2 terminal input, 3 terminal output transformers. But the particular one i got is having 6 output terminal. Also, there is an insulated ...
2
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2answers
128 views
Electrical circuit / transformer in series?
I would like to pull out 5v 3A max in series from an already existing connection from the mains 240v 40A connection.
Current circuit:
What I would like to implement:
What are the possible ...
0
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1answer
118 views
Replace Expensive Transformer with cheaper alternative? [closed]
I have a range hood that has an expensive (IMO) transformer that has went bad. Here is the link to the transformer that went bad: ...
2
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3answers
141 views
What is a secondary transformer?
On a number of projects I'm building, there's a transformer between wall power and device power. In the parts lists, the transformers are usually designated by "12v secondary transformer" or "18v 4a ...
3
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2answers
222 views
Question about transformer design
I want to use a transformer to convert AC voltage. Input is 220V AC at 50 Hz and output is, for example, 5V 30mA AC.
Many people told me, this transformer will be huge because the mains frequency is ...
10
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3answers
639 views
Cellphone charger has no transformer?
I opened up a really tiny mobile phone charger I have, to see how it is designed. The entire "charger" is integrated into a small 2-pin mains plug, 1 x 1.25 x 0.5 inch, that has an USB socket for the ...
0
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1answer
114 views
can a fan regulator could act as a transformer?
what are we actually reducing and increasing on changing the regulator value? Current,voltage.? Is it based on resistance or capacitance? Power losses?
Can a regulator can be used for current ...
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2answers
53 views
subsituting one transformer for another [duplicate]
Possible Duplicate:
Choosing power supply, how to get the voltage and current ratings?
I have an eliptical machine that is no longer being manufactured. it appears that the AC to AC adaptor ...
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2answers
532 views
How to use a transformer to power a 5V chip (an Atmega328)?
I am designing an Atmega328 based device which needs to be powered directly from 230V AC. I have found a transformer in my local electronics store which seems perfect, but I have never worked with ...
2
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1answer
213 views
Why high voltage from TV flyback shocks you without the need to complete a circuit?
Assuming the TV is plugged into an isolation transformer (although I think there is already a small transformer onboard), then ground is not part of the secondary side. Yet, high voltage from flyback ...
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2answers
153 views
Controlling Transformer Output
I want to control the output of a transformer. So the input is 220V, 50 Hz. I am stepping it down to 24V. Now I want a switch that can vary the output between 0-24v. How do I make such a switch? If I ...
3
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1answer
318 views
Simulating real world transformer with LTSpice
I'm studying LTSpice, and I'm playing in transformer simulation. I want to modelize a real world power line transformer in a reasonable way: I mean I don't need an exact simulation of some specific ...
