Mains / USB Chargers

Pete Gl

Pete Gl

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Are all of the above the same? IE Are chargers for 10" tablets a higher output than, for example a phone or Kindle. If so is it safe to charge a phone / Kindle from these higher output chargers?

Many thanks in anticipation,

Pete
 
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The output rating is the maximum it can give. If a device requires 0.3A, it will take that from a 0.5A charger or a 2A charger. As long as the charger can deliver equal to or greater than the required current, it will be o.k.

A device will not take more current just because it is available.

I assume you are referring to devices charged via a USB connection. If so, all are compatible.


Steve.
 
There's an app called "Ampere" which I use on my Samsung to compare outputs of chargers.

The S6 charger is 2A, old Hauwei chargers around 0.5A, Sony one from my tablet is around 1A.
 
So, is the charger supplied with my phone likely to be a lower output than the one supplied with a 10" tablet? I ask because if I use my phone charger to recharge my tablet it seem to take an awful long time.

Pete
 
Pete Gl said:
So, is the charger supplied with my phone likely to be a lower output than the one supplied with a 10" tablet? I ask because if I use my phone charger to recharge my tablet it seem to take an awful long time.

Pete
Click to expand...

If it's like our Apple iPhone and iPad charger, then yes, they are different outputs ... it should (possibly) tell you somewhere on the charger the output, so you can check.
 
Apple adaptors have their output written on the back of the plug and I think most others should too? Most dedicated tablet chargers have a 2amp output so if you're using a 0.5 amp phone charger it will take 4x longer to fully charge.
 
As others have said, yes! - chargers to have different output levels. Often, tablets will charge with higher output chargers than phones. For example, I have a charger for my iPhone and one for my iPad (the regular one, not the mini). The iPad one has a higher current delivery than the iPhone one and needs this - the iPad would take a long long time to charge from the iPhone charging plug. The iPhone, however, is quite happy being charged by the iPad charger.
There are also many third-party high level chargers available on the market to fix this problem - however, do please be careful, some of them (particularly the cheaper ones) are not well made/designed and could pose to be hazardous. You can tell this if you get one of these third-party charging plugs and it gets very hot when in use - if it does get very hot then you might want stop using it. As we all pay quite a lot of money for our electronic devices I always suggest to people that it is best to also invest in good quality chargers and cables should these be needed - these are less likely to be a fire risk and are also less likely to damage your equipment.
 
I have an old phone charger around that will barely charge my Note 2 if I am using it.
as folk have said its all about the output versus the requirement.

I think the voltage is the same as its a spec of USB
 
Andy Taylor said:
This is a great example of why you should buy decent quality chargers:

http://www.righto.com/2014/05/a-look-inside-ipad-chargers-pricey.html
Click to expand...

MMMM a very thorough and extremely impressive dissection of the difference between the genuine article and a counterfeit one.

And note that this difference doesn't just apply to Apple but to any counterfeit goods especially electrical goods where the saving of a few pennies may lead to a much more expensive funeral!
.
 
On the other hand there is no need to spend a fortune (particularly on an apple charger), there are many good 3rd party USB chargers out there.

Counterfeit and 3rd party are not the same thing. :)
 
Pete Gl said:
So, is the charger supplied with my phone likely to be a lower output than the one supplied with a 10" tablet? I ask because if I use my phone charger to recharge my tablet it seem to take an awful long time.

Pete
Click to expand...

Phone chargers have a lower output than a tablet charger. It is totally up to you, but at your own risk, to use them in a crossover fashion, ie: use phone charger for tablet and/or tablet charger for phone, but like others said, there is a risk of damaging your devices. The kind of damage is most likely, at minimum, to be battery playing up after many months, such as it no longer last you 10 hours, it now last you 3 or 4 or 5 hours, but at worst, battery burns or whatever. So again, at your own risk.

As you have found out that using phone charger (which supplied lower output) to charge up tablet will take a long time. This is typical, including the Apple chargers for iDevices. iPod/iPhone use a 5w charger while the iPad use a 10w charger (at that time I got my first generation iPad some 5 years ago), so when I charge the iPad using the 5w charger, it will take the iPad twice longer to charge up.

It's a bit like trying to fill up a F1 racing car with a normal garage petrol pump (taking ages to fill up) or trying to fill up your own family car with one of those high pressure petrol pumps normally used for refuelling F1 cars (too fast and you suddenly find yourself overflowing your car's petrol tank before you even noticed).
 
Major Eazy said:
It's a bit like trying to fill up a F1 racing car with a normal garage petrol pump (taking ages to fill up) or trying to fill up your own family car with one of those high pressure petrol pumps normally used for refuelling F1 cars (too fast and you suddenly find yourself overflowing your car's petrol tank before you even noticed).
Click to expand...

And in another, more accurate way, it's nothing like that. A 10 watt charger will not force more current into a phone than it needs and would normally take from a 5 watt charger.

The first half of your analogy is correct though).


Steve.
 
Major Eazy said:
use them in a crossover fashion, ie: use phone charger for tablet and/or tablet charger for phone... there is a risk of damaging your devices
Click to expand...
Show us the evidence that proves your statement is true
 
redsnappa said:
Show us the evidence that proves your statement is true
Click to expand...

There is none. The lower rated charger trying to charger the more current hungry device might get a bit warmer than normal but the devices being charged will not be damaged.


Steve.
 
neil_g said:
not necessarily, the hudl2 for example will not charge on anything less than its own charger. dont ask me why.
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The Hudl2 charger behaves oddly, producing what appears to be a pulsing voltage that does odd things when plugged into my Motorola phone.
 
Major Eazy said:
Phone chargers have a lower output than a tablet charger. It is totally up to you, but at your own risk, to use them in a crossover fashion, ie: use phone charger for tablet and/or tablet charger for phone, but like others said, there is a risk of damaging your devices.
Click to expand...

Totally untrue, as an example, look at the Apple product pages and the iPad charger is listed as a compatible alternative to the standard charger for any iPhone. In fact, the iPhone 6 and 6s have been engineered so that they can actually use the higher power to charge the phone quicker.

A 2.4A charger can charge anything that requires up to 2.4A, a 1A device will just take 1A from the charger.
 
Dave1 said:
Totally untrue, as an example, look at the Apple product pages and the iPad charger is listed as a compatible alternative to the standard charger for any iPhone. In fact, the iPhone 6 and 6s have been engineered so that they can actually use the higher power to charge the phone quicker.

A 2.4A charger can charge anything that requires up to 2.4A, a 1A device will just take 1A from the charger.
Click to expand...

And conversely, an iPad connected to a 1A charger will take the maximum 1A and charge more slowly. Clever stuff.
 
We've got a few wall sockets with USB outlets dotted around in places where we usually charge devices. IIRC they deliver 2.1A so about 10W. Work well and have never caused any problems.
 
Nod said:
We've got a few wall sockets with USB outlets dotted around in places where we usually charge devices. IIRC they deliver 2.1A so about 10W. Work well and have never caused any problems.
Click to expand...

I have a few of those to fit. Neater than plug in chargers.


Steve.
 
Steve Smith said:
And in another, more accurate way, it's nothing like that. A 10 watt charger will not force more current into a phone than it needs and would normally take from a 5 watt charger.

The first half of your analogy is correct though).


Steve.
Click to expand...

I don't meant how much power go into charging the battery, I meant how fast/slow it takes to charge the battery.
 
Major Eazy said:
I don't meant how much power go into charging the battery, I meant how fast/slow it takes to charge the battery.
Click to expand...

The analogy is still flawed though.

Think about mains electricity. An electrical socket doesn't know what you are going to plug into it. It could be an electric fire (2kW) or a USB charger (5W). The electric fire will draw about 8.5A, the charger will draw just over 0.02A. The socket won't try and force more power into the charger than it can handle.
 
Major Eazy said:
I don't meant how much power go into charging the battery, I meant how fast/slow it takes to charge the battery.
Click to expand...

Yes, but you likened a higher powered charger to a high pressure F1 car petrol pump suggesting that it will force more charge into the device than it needs. That won't happen. It will just take as much current as it needs to charge properly and ignore any extra capacity.
The current rating of a charger is the maximum it will give, not the current it will put out all of the time regardless of load... Unlike a high pressure petrol pump which will flow at full speed until you turn it off!

Another way of looking at it is to think of it in terms of light bulbs. The socket on the ceiling can take any size of bulb from 5 watts up to 150 watts. The bulb dictates the power, not the outlet.


Steve.
 
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Andy Taylor said:
And conversely, an iPad connected to a 1A charger will take the maximum 1A and charge more slowly. Clever stuff.
Click to expand...

Unfortunately not.

Apple changed iOS so that it would refuse to even attempt to charge on a 1A supply. I guess they wanted to avoid all those complaints about it taking a long time to charge.
 
hollis_f said:
Unfortunately not.

Apple changed iOS so that it would refuse to even attempt to charge on a 1A supply. I guess they wanted to avoid all those complaints about it taking a long time to charge.
Click to expand...

My iPad Air charges without any problem using a 1A charger from the my iPhone...

Just slower.
 
Dave1 said:
My iPad Air charges without any problem using a 1A charger from the my iPhone...

Just slower.
Click to expand...

Does it do what mine does on a 1A supply? Mine displays the message 'Not Charging'. I've always believed that, but it seems it may be a lie.
 
hollis_f said:
Does it do what mine does on a 1A supply? Mine displays the message 'Not Charging'. I've always believed that, but it seems it may be a lie.
Click to expand...

No, it shows the normal charging symbol, I tested it last night before making my post.

"Not charging" is often a sign of a non-genuine or fake charger or lead.
 
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if you guys want to read up on usb charging then this gives a pretty good summary...
https://www.maximintegrated.com/en/app-notes/index.mvp/id/4803

The main problem is that, despite there being a spec everyone should follow, some devices handle different chargers better than others and some chargers don't actual stick to the specs very well.

For example, my LG G2 goes a bit mad (flashing its notification when fully charged when charged through my monitors USB hub (which meets the spec as far as I can tell). From what I have read this is a pretty common problem with the G2.
And I have a generic 2A charger that actually gives out 5.5V whereas the usb spec is 5.25V max I believe.

That said, It would be a pretty shoddy product design that didn't cope with a pretty wide variation in charger output.
 
neil_g said:
not necessarily, the hudl2 for example will not charge on anything less than its own charger. dont ask me why.
Click to expand...
Hi neil_g I use my Samsung Note 2014 edition & my ZTE phone charger to charge my Hudl 2 when I can't be bothered to find the actual Hudl 2 charger.
The Sansung take the same amount of time to charge the Hudl 2 while as expected the ZTE phone charger takes a lot longer.

On that note I often use the Hudl 2 or Samsung chargers to 'Boost' charge the phone because unlike this post;
Steve Smith said:
The output rating is the maximum it can give. If a device requires 0.3A, it will take that from a 0.5A charger or a 2A charger. As long as the charger can deliver equal to or greater than the required current, it will be o.k.

A device will not take more current just because it is available.
Click to expand...

A device will take more charge if it is available.
My phone charger is only 500mha but sticking on to the Samsung or Hudl 2 charges they are 10 times that & the phone charges in 90 minutes from flat instead of the usual 5 hours.
 
All clear now, I often am not as clear as I write, it's in the head but doesn't appear on the page/screen. :-)
 
There is a caveat to all this though. As I said earlier, It does assume the phone is designed properly! Some are better than others but I haven't heard of a recent design that would damage anything if put on a supply capable of giving more than the phone can cope with. Lets face it, it has to cope when plugged into a usb hub which could have an indeterminate supply current.

Looking at it more technically a Li-Ion battery should be charged at up to 1C during the early phase of charging then at constant voltage to top it right up. You can go higher but it starts to reduce the battery life. (plus I might be a bit out of date with battery capability....)
So if you battery is 2500mAh then it can take at 2.5A charge current. Like has been said, that will be limited by the phones charging circuit, not the charger.
 
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