Samsung mobile charger difference in power

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Discussion Overview

The discussion revolves around the differences in power ratings between a Samsung mobile charger’s input and output specifications. Participants explore the implications of these differences, particularly in terms of energy consumption and efficiency, while considering the nature of AC to DC conversion.

Discussion Character

  • Technical explanation
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant calculates the input power of the charger to be 36W and the output power to be 2.6W, questioning the significant difference between them.
  • Another participant suggests that the input current rating is often a suggested minimum rather than an accurate measure of typical consumption, indicating that AC power cannot simply be calculated as "VI".
  • A participant expresses concern about energy wastage and questions whether it is possible to convert the same amount of power consumed by the mobile device from AC to DC to reduce losses.
  • One reply mentions that the perceived power loss may not be significant and highlights the confusion surrounding safety agency ratings for current.
  • Another participant emphasizes that ratings may not reflect actual operating values and suggests measuring power consumption directly for accuracy, noting the existence of devices that can measure power usage.
  • A participant asserts that the actual current drawn would likely be less than the rated input current and estimates that charger efficiency should be greater than 50%.
  • One participant references an external link to support their understanding that a charger functions similarly to an AC to DC adapter.

Areas of Agreement / Disagreement

Participants express various viewpoints regarding the efficiency and power ratings of chargers, with no consensus reached on the implications of the input and output power differences or the efficiency of the charger.

Contextual Notes

Participants note that input ratings may not accurately reflect actual consumption, and there are unresolved questions about the efficiency of the charger and the methods for measuring power consumption.

vidhyarthi
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Hi friends, I have a samsung mobile charger with specifications as
Input: 150-300V AC and 0.15A
Output: 4.75V DC and 0.55A
So now by P=VI
the input power is 36W (taking 240V AC and unity PF)
and output power is 2.6W.
So my doubt is why there is such difference the power of i/p and o/p??
because if we have low i/p power we can have a less amount of energy consumed.
 
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"Input: 150-300V AC and 0.15A"

For many devices the input current rating is more of a suggested minimum rating for the power source you should use rather than an accurate measure of the typical current that the device will consume.

BTW. You can't necessarily calculate the AC power as "VI" anyway.
 


Thanks uart so from your reply i understand that input current is more than rated even then4 the input power is more. And even we take power factor into consideration it is more than output DC power. Now what I'm asking is can't we take the same amount of power which is consumed by the mobile and convert that from AC to DC to save such wastage of energy?
 


Does it feel like a 20 watt as it's running? If not, than you may consider that it is not lossing so much energy. The safety agency ratings for current can be confusing and you generally cannot rely on them for power ratings. Also, the chance of such a tiny supply having power factor correction, are close to non-existent...
 


Ratings like that don't necessarily denote the actual operating values of the device. Usually it would just be safe maximums or things like that. The only way to be sure of the power is to actually measure it while it is being used. I know there is a device called the Kill-a-Watt sold in the US that can measure the power taken from a wall outlet. I'm sure there are similar devices sold for your country.

I find it highly unlikely that a charger would have less than 10% efficiency.

Also, write better post titles. Generic things like "Help!" are useless and annoying.
 


input current is only indicative for 150/300V source, actual current would be lesser. and charger efficiency should be >50%
 

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