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Old Nov 19, 2012, 02:15 AM   #26
gmanist1000
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Originally Posted by bushman4 View Post
Fact is Fact. Anyone that owns a 12w charger use it on your Iphone5 and let us know. I've compared the charging times and I can say from actual test it only tales 3/4 the time that the 5w charger takes to charge the Iphone5.
Here's proof the iPhone draws 5W from the 12W charger.

http://www.youtube.com/watch?v=DC4gPxc89Wg&sns=em
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Old Nov 19, 2012, 03:19 AM   #27
WilliamG
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Originally Posted by gmanist1000 View Post
Here's proof the iPhone draws 5W from the 12W charger.

http://www.youtube.com/watch?v=DC4gPxc89Wg&sns=em
Yep, there's proof indeed. I can't even fathom why people think the 12W charger is any faster with an iPhone...
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Old Nov 19, 2012, 03:35 AM   #28
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Originally Posted by Radiating View Post
In case anyone had any doubts as to the iPad charger charging faster:
That only tells us that one charger draws more mains power than the other. While I don't doubt that an iphone can draw more than 1 amp, the differences you're getting could just as easily be the result of variances in charger overhead/loss, at least partly.

If you want to measure an iphone's power draw accurately you need an amp meter and a usb cable to sacrifice.
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Old Nov 19, 2012, 03:39 AM   #29
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Can anyone tell me if THIS ADAPTOR is the three prong plug used in England or not... The store doesn't say either way

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Old Nov 19, 2012, 08:08 AM   #30
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Originally Posted by Archer1440 View Post
If only factual posts were made here, there would only be half the posts.

The iPhone 5 can only draw a bit over 5 watts no matter what the capacity of the charger, put an in-line meter on the circuit and prove it for yourself as I have.

The 12W charger (I have two) DOES charge the iPad 3 faster, but only by 45 minutes or so. It can draw up to 13W.

The 12W charger stays a lot cooler than the 5W on the iPhone and the 10W on an iPad. This should translate to a longer service life. So there's no reason not to use the 12W on the iPhone- but it won't charge faster.
THIS! everybody thinks the iPad chargers charge iPhones faster but they are wrong!
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Old Nov 19, 2012, 08:27 AM   #31
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Originally Posted by InfinitiG View Post
sorry but the iphone can accept only 5W .... dream on
Like I said, iPhone can only accept 5W.
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Old Nov 19, 2012, 12:58 PM   #32
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Originally Posted by Archer1440 View Post
If only factual posts were made here, there would only be half the posts.

The iPhone 5 can only draw a bit over 5 watts no matter what the capacity of the charger, put an in-line meter on the circuit and prove it for yourself as I have.

The 12W charger (I have two) DOES charge the iPad 3 faster, but only by 45 minutes or so. It can draw up to 13W.

The 12W charger stays a lot cooler than the 5W on the iPhone and the 10W on an iPad. This should translate to a longer service life. So there's no reason not to use the 12W on the iPhone- but it won't charge faster.
This is the only post in this thread that needs to be read.
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Old Nov 19, 2012, 01:44 PM   #33
Radiating
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Originally Posted by chambone View Post
That only tells us that one charger draws more mains power than the other. While I don't doubt that an iphone can draw more than 1 amp, the differences you're getting could just as easily be the result of variances in charger overhead/loss, at least partly.

If you want to measure an iphone's power draw accurately you need an amp meter and a usb cable to sacrifice.
That's not how electricity works. If the iPad charger was really half as efficient as the iPhone charger it would melt itself. The electricity has to go somewhere and the chargers already. Current chargers are 85%-95% efficient and the less efficient ones already read 100 degrees. If the iPad charger was half as efficient as the iPhone charger it would literally catch fire and explode.

Also the iPad takes 10 watts of power while charging so it would have to take 20 watts if the silly "overhead" concept were true.
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Old Nov 19, 2012, 01:56 PM   #34
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Originally Posted by Radiating View Post
That's not how electricity works. If the iPad charger was really half as efficient as the iPhone charger it would melt itself. The electricity has to go somewhere and the chargers already. Current chargers are 85%-95% efficient and the less efficient ones already read 100 degrees. If the iPad charger was half as efficient as the iPhone charger it would literally catch fire and explode.

Also the iPad takes 10 watts of power while charging so it would have to take 20 watts if the silly "overhead" concept were true.
Whats silly is trying to determine a device's power draw by measuring the power drawn from mains by its charger. Anything other than measuring from the usb cable is pointless.
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Old Nov 19, 2012, 02:23 PM   #35
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Originally Posted by chambone View Post
Whats silly is trying to determine a device's power draw by measuring the power drawn from mains by its charger. Anything other than measuring from the usb cable is pointless.
No it's not, you can use simple logic to determine something is true without directly measuring it.

For example:


We know that AC to DC chargers of normal modern design are 85%-95% efficient. The iPad charger draws 70% more power than the iPhone charger when it is charging an iPhone 5. Therefore we know that the iPad charger charges the iPhone 5 with more power than the regular charger, if it is a charger of normal modern design.


We know that the iPad charger draws 10 watts while charging the iPad, which takes more power to charge than the iPhone. The iPad charger also draws 10 watts while charging the iPhone 5. Therefore we know that the iPad charger is charging the iPhone with more power.

The iPad charger draws 70% more power than the iPhone charger when it is charging an iPhone 5. We know that any electricity taken out of the mains that is wasted in a charger has to go to heat. The iPad charger would have to waste 6-10 times more energy than the iPhone charger to maintain it's power draw and charge at the same rate. This level of heat would cause a fire. The iPad charger is not on fire when it charges the iPhone 5, therefore we know that the iPad charger charges the iPhone with more power than the regular charger.


Do they not offer basic logic and reasoning classes in the Netherlands?
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Old Nov 19, 2012, 02:52 PM   #36
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And again the condescending attitude. Is that normal where you come from? There's no need to feel attacked.

By your logic an ipad charger charges the iphone5 70% faster. Do you really think this is true?
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Old Nov 19, 2012, 03:48 PM   #37
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Well, the actual current draw is limited by the device (Phone), not the charger, unless the draw is greater than the charger can provide.

If the iPhone can draw 6w instead of the 5w in the specs. then it would charge faster with an iPad charger. All one has to do is test. I have both chargers but I don't have any interest at this point.
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Old Nov 19, 2012, 04:26 PM   #38
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Originally Posted by chambone View Post
And again the condescending attitude. Is that normal where you come from? There's no need to feel attacked.

By your logic an ipad charger charges the iphone5 70% faster. Do you really think this is true?
Nope.
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Old Aug 29, 2013, 04:06 AM   #39
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iPhone 4S will not charge faster

I tested the iPhone 4S. I can't confirm the iPhone 5 (I don't have one) but I'm almost certain it isn't any different.

I used this USB Power Meter I got on Amazon.com
http://www.amazon.com/Centech-USB-Po.../dp/B00DAR4ITE
I also double checked by splitting open a cable and using a digital multimeter (ammeter.)

iPhone 4S draws 0.93 amps when rapid charging (screen off) and 1.03 amps (screen on.) That's 5 watts (at 5 volts USB.) It does so on the 10 watt iPad 2 charger, 5 watt iPhone charger, as well as 11 other 3rd party adapters including a 15 watt adapter.

iPad 2 draws about 1.98 amps rapid charging with the screen on and 1.87 amps rapid charging (at 5 V) with the screen off.

So I can say without a doubt, an iPhone 4S will never charge any faster with any adapter over 5 watts than it will with the 5 watt adapter. Again, I can't say for 100% certain that the iPhone 5 is the same but other evidence I've seen indicates it is the same.

The iPhone limits itself to using only 1 amp during rapid charging. That's all there is to it.

Also note that some super cheap 3rd party cables, especially super long ones will restrict power flow to less than 1 amp (5 watts.) So stick with MFI certified, name brand, or genuine apple cables or you could see slower charging on all adapters.

----------

Quote:
Originally Posted by meistervu View Post
Well, the actual current draw is limited by the device (Phone), not the charger, unless the draw is greater than the charger can provide.

If the iPhone can draw 6w instead of the 5w in the specs. then it would charge faster with an iPad charger. All one has to do is test. I have both chargers but I don't have any interest at this point.
Agreed.

And as I mention in my previous post the iPhone will actually spike up to 1.05 amps even from from the 1 amp charger when initially connected and quickly (within a few seconds) settle to 1.03 amps with the screen on while charging. It uses about 0.93 just rapid charging with the screen off.

So one might see a rounding up to 6 W as the iPhone pulls just slightly over 5 W depending on how they measure the power draw.
If they used a watt's up like they did in the youtube video, then they may be seeing overhead of the actual adapter converting the power to DC which might be just enough to bump it to 6 W when it's actually delivering 5 W to the phone.

I measured the actual amperage on the 5 V USB power line. I did over 50 tests with different cables and adapters with the same exact results every time.

Pretty much end of discussion.

Last edited by RF9; Aug 29, 2013 at 04:14 AM.
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Old Aug 29, 2013, 06:28 AM   #40
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Originally Posted by InfinitiG View Post
sorry but the iphone can accept only 5W .... dream on
Fact is that the iPhone charges faster with the iPad charger. And actually a lot faster.
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Old Aug 29, 2013, 06:43 AM   #41
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My iPhone 4s definitely takes less time with the 2A charger than the old 1A one, but mainly from a flat state, once it's near full the charge rates are the same and the both drop off as the battery comes up to full anyway.

Definitely faster from flat though during bulk stage.
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Old Aug 29, 2013, 12:31 PM   #42
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My iPhone 4s definitely takes less time with the 2A charger than the old 1A one, but mainly from a flat state, once it's near full the charge rates are the same and the both drop off as the battery comes up to full anyway.

Definitely faster from flat though during bulk stage.
This was also true of the 3rd gen iPod touch. And it's true of the 5th gen iPod touch as well.

The reason for the drop off when near the full charge is the trickle charge to full as the battery cools off from charging.
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Old Aug 29, 2013, 01:48 PM   #43
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Yep, there's proof indeed. I can't even fathom why people think the 12W charger is any faster with an iPhone...
placebo?
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Old Aug 29, 2013, 02:07 PM   #44
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Originally Posted by Radiating View Post
No it's not, you can use simple logic to determine something is true without directly measuring it.

For example:


We know that AC to DC chargers of normal modern design are 85%-95% efficient. The iPad charger draws 70% more power than the iPhone charger when it is charging an iPhone 5. Therefore we know that the iPad charger charges the iPhone 5 with more power than the regular charger, if it is a charger of normal modern design.


We know that the iPad charger draws 10 watts while charging the iPad, which takes more power to charge than the iPhone. The iPad charger also draws 10 watts while charging the iPhone 5. Therefore we know that the iPad charger is charging the iPhone with more power.

The iPad charger draws 70% more power than the iPhone charger when it is charging an iPhone 5. We know that any electricity taken out of the mains that is wasted in a charger has to go to heat. The iPad charger would have to waste 6-10 times more energy than the iPhone charger to maintain it's power draw and charge at the same rate. This level of heat would cause a fire. The iPad charger is not on fire when it charges the iPhone 5, therefore we know that the iPad charger charges the iPhone with more power than the regular charger.


Do they not offer basic logic and reasoning classes in the Netherlands?
Just because you try and make it sound logical, doesn't mean that it is logical. Your logic is way off and not worthy of being called 'logic'. You clearly haven't got a clue.

Further to that, the Dutch are amongst the most logical and reasoned people on the planet. Once again it's clear that you haven't got a clue!
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Old Aug 29, 2013, 04:30 PM   #45
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every body says it charge faster and not faster, but please just MEASURE IT !!!

Take your iphone and put it in charge when he is at 5% and take your clock.
When it is at 100%, take another the clock and see how many minutes.

Do the same thing with 5W charger and 12w charge and stop saying that it charge faster or not, please please !!!!!
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Old Aug 29, 2013, 05:07 PM   #46
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I think everyone should just check out this video so we can finally put this debate to rest.

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Old Aug 29, 2013, 05:46 PM   #47
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I have an iphone 5, the wife has an iphone 5.

I ran them both down to zero

Plugged one into a 5w charger and one into a 12w charger

Both charged at EXACTLY the same rate.
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Old Aug 30, 2013, 05:24 AM   #48
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Originally Posted by Sym0 View Post
My iPhone 4s definitely takes less time with the 2A charger than the old 1A one, but mainly from a flat state, once it's near full the charge rates are the same and the both drop off as the battery comes up to full anyway.

Definitely faster from flat though during bulk stage.
I can tell you that absolutely unequivocally that is not correct. Read my post. I tested this 50 times and the iPhone 4S always always always draws the same exact amount of power when rapid charging. I don't have a iPhone 5 so I can't prove it myself, but I've seen other people's test that show the same thing.

Rapid charging is to 80%, then drops off gradually as it increases to 100%.
So make sure you're comparing apples to apples. Measure how long it takes to get from say 40% to 60%, but don't compare above 80% because it's not a flat rate.
Also make sure you're testing with the SAME cable on APPLE adapters.

If you're using a 3rd party cable on the iPhone adapter and a shorter Apple cable on the iPad adapter, then there's your problem, some 3rd party cables will never deliver a full 1 amp.

My tests were done with the Apple 30 pin cable with the Apple iPhone 5 W adapter and the Apple 10 W iPad 2 adapter.
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Old Aug 30, 2013, 09:30 AM   #49
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The major problem here is probably NO ONE has any clue as to what the CURRENT charge on the battery was when they began to charge it for their "scientific test." Despite the fact the battery meter says 20% left it could be 5% or 10% or 50% or anything in between. Even if if the phone shuts itself down you still don't know what the state of the battery charge is.

Unless testing is done with full and accurate knowledge of the battery's current state of charge all this discussion is meaningless.

That being said (and I think most everyone agrees with this) any device's charge rate is limited to how it's hardware charging circuitry is designed. It is possible that maybe there is some small variation of charge rates between phones but not enough to make one phone "charge 45% faster."

Bottom line is unless you know the exact state of the battery when charging begins measured by accurate test equipment most everything in this thread is unverified conjecture (except for those who say a 5 watt or 12 watt or 500 watt charger will charge the phone at the identical rate).
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Old Sep 5, 2013, 11:17 AM   #50
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The major problem here is probably NO ONE has any clue as to what the CURRENT charge on the battery was when they began to charge it for their "scientific test." Despite the fact the battery meter says 20% left it could be 5% or 10% or 50% or anything in between. Even if if the phone shuts itself down you still don't know what the state of the battery charge is.

Unless testing is done with full and accurate knowledge of the battery's current state of charge all this discussion is meaningless.

That being said (and I think most everyone agrees with this) any device's charge rate is limited to how it's hardware charging circuitry is designed. It is possible that maybe there is some small variation of charge rates between phones but not enough to make one phone "charge 45% faster."

Bottom line is unless you know the exact state of the battery when charging begins measured by accurate test equipment most everything in this thread is unverified conjecture (except for those who say a 5 watt or 12 watt or 500 watt charger will charge the phone at the identical rate).
Or... Just use a Kill-A-Watt plug that will tell you the power draw. That's all we care about.
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