Home > power > transformer conservation of power

transformer conservation of power

October 16Hits:1
Advertisement

lets say we have a transformer, on the left side, it is 220 v and on the right side, it is 10 v. we know that power is conserved meaning power on left is equal to right (ignoring loss). I understand how voltage is stepped up or down (induced emf on the other side, if there are more coils, it will produced more emf and so it will stepped up, vice versa), but how does it actually make the current low or high (or adjust), to make the power still equal?

Answers

In a perfect transformer run in forward mode, the change in secondary current exactly ballances the change in primary current to keep the magnetic flux the same.

This means the effective current going around the core in each of the primary and secondary must be the same but in opposite direction. The transformer only sees the current going around the core. The multiple turns of a winding only make it look like more current overall going around. To the core, 13 turns of 1 A each is the same as 26 turns at 1/2 A each. The same overall current is still circling the core.

The current that actually flows thru each winding from the external circuit point of view is the current thru each winding since they are effectively in series. The external current is therefore inversely proportional to the number of windings.

Let's say your transformer has 100 A circling the core. That might be 880 turns on the primary, for 114 mA thru the primary from the outside point of view. In this case, the secondary would have only 44 turns. For the ideal case, this would also have to produce 100 A circling the core. Since each turn only contributes 1/40 of that, the current thru the secondary wire needs to be 2.5 A.

Related Articles

• transformer conservation of powerOctober 16

lets say we have a transformer, on the left side, it is 220 v and on the right side, it is 10 v. we know that power is conserved meaning power on left is equal to right (ignoring loss). I understand how voltage is stepped up or down (induced emf on t

• Transformer core maximum powerNovember 19

so i am an EE undergrad, and i am wondering if and how exactly does a transformer core limit its power capacity. From my understanding, the rated power of a transformer is due to the current carrying capacity of its windings. As far as the core is co

• Why the delay between transformer failure and power outage?November 1

A friend witnessed the explosion of the 14th street substation. I believe these transformers, about 1 city block in extent, delivered power to most of lower Manhattan. I am guessing the flood water obstructed cooling, and they overheated and exploded

• Transformer for Flyback power supplyJune 6

I am designing an isolated DC-DC converter with an input of 12V and an output of 5V@12A, at the moment, a flyback seems like the best option. I have read several books regarding the subject and I am proceeding to the implementation; however, I haven'

• Can I use a halogen transformer as a power supply?November 29

I have an electronic transformer which is meant to be used to drive a 12v halogen light. The specification on the electronic transformer box says 220-240VAC input, 12VAC output 20-60W. When a 50W halogen bulb is connected to this electronic transform

• Can I Use Current Sensing Transformer Instead of Power TransformerMay 7

This is a follow-up on this question: How to Design Arduino Voltage and Current Sensing Shield Thanks to user bigjosh, I read the article: http://openenergymonitor.org/emon/buildingblocks/measuring-voltage-with-an-acac-power-adapter and I started des

• Three questions about the use of a transformer in switching power-supplyAugust 26

In this document (an introduction to switching power supplies) a boost-mode switching power supply is presented: it has a simple inductor, diode, capacitor and load. Then (page 9) it is specified that this device can be used only for input voltages n

• Transformer model in Power Systems VS Coupled Inductors modelNovember 15

I know 2 models for a transformer one is to treat it as Coupled Inductors and the model will be: In this model if there are no flux leakage the coupling factor is k=1 and therefore $$M=k\sqrt{L_1L_2}=\sqrt{L_1L_2}$$ But In power systems analysis, the

• I'm replacing a 24VAC transformer that supplies power to a motorized skylightDecember 2

I could use some help selecting a replacement transformer with the correct amps. The transformer supplies power to a PCB that switches a small low-speed hi-torque motor via a battery operated remote control to lift and shut the skylight. The skylight

• Fast Fourier Transform (FFT) of power consumption signalsDecember 3

I want to compare two power consumption signals, i.e., how the power consumption varies throughout a day. Now I have two options: Take two raw power signals and compute the Euclidean distance between them Convert the input power signals using Fast Fo

• Transformer VA Ratings, Power factor, and Pulsed currentDecember 23

What exactly goes into a transformer's VA rating? At a fundamental level it seems that there has to be a limit to what the VA rating can represent. For example if I draw 2 Amps-RMS from the secondary of a 30VA rated transformer at 15 Vrms this makes

• How is power affected on a step-up transformer, does it change?September 22

Ok here is what I have found so far about Step up and step down transformers: Step down transformers change a high voltage/low current, to low voltage/high current. Step up transformers change a low voltage/high current, to high voltage/low current.

• Can the clock speed of my 2011 MBAir i7 be slowed to conserve power?January 13

Most of what I do with my 2011 i7 MBAir could be done with 10% of the available processor power. Is there a hack to slow the processor to conserve battery for the 95% of the time I don't need it? --------------Solutions------------- The Intel i5 and

• What's the maximum power capacity of a transformer with super conducting wire?April 12

If I wind a specific transformer with superconducting wire and take away temperature from the core by means of some way, how much power can I take from transformer? I should mention max power capacity of that transformer with normal copper wire is 10

• Power multiple 5V/12V devices off a single transformer? February 12

This question is an exact duplicate of: Power block to feed multiple 12V/5V devices? [closed] 1 answer I have these devices in my cabinet (Q-Panel) that have these power requirements: 21V 1.2Amp 5V 500mA 12V 1.5A 12V 1.5A 48V 1.25A Obviously I can't

• Transformer output connected to another transformer. Measuring 'Real Power' at input of first transformerJanuary 27

I have a watt meter connected to the primary of one transformer to measure power. The output of this transformer is connected to the input of another transformer. The watt meter is measuring the inductive load of the primary of the second transformer

• The right sequence connecting a power supply to a deviceJuly 5

Since I heard two versions and also read two versions in manuals to various devices, I would now like to hear the community opinion. How should we connect a power supply to an electronic device? Option 1: Connect the PS to the device, then plug the P

• How can I set my laptop on power saving mode? Processing and downloading should continueNovember 5

I have a very slow Internet connection at home. If I want to download some 1 GB of data from Internet, I usually keep my laptop on for the whole night. I use Flashget as my downloader. I want to do something by which most of the hardware which is not

• Ubuntu using up battery power too quickly July 29

This question is present as a matter of historical interest. While you are encouraged to help maintain its answers, please understand that "big list" questions are not generally allowed on Ask Ubuntu and will be closed per the FAQ. It is possibl

• Battery power indicator bug and high power consumption on 12.04 July 29

This question is present as a matter of historical interest. While you are encouraged to help maintain its answers, please understand that "big list" questions are not generally allowed on Ask Ubuntu and will be closed per the FAQ. It is possibl

Copyright (C) 2017 ceus-now.com, All Rights Reserved. webmaster#ceus-now.com 14 q. 0.541 s.