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OEM Charger/Cable amperage

F

freakshow85

Android Enthusiast
Hey, I was curious if anyone knew how many amps the stock cable that comes with the S3 charger can handle. The charger that came with my StraightTalk S3 is rated to charge at .7 amps.. which equaled a very slow charge if I was gaming at the same time.

So I bought an aftermarket charger and was curious if my cable is able to take advantage of the extra amperage. I have Battery Monitor Widget and will test again when I'm at a lower battery charge, but from 80-88%, I never saw more than .7 amps being drawn. Same as with my last charger.

Edit: I also see everywhere that the OEM charger that people get with their S3 is a 1 amp charger. The charger that came with my Straight Talk S3 says .7 amps on the adapter. It may be a universal Samsung charger they sent out with these versions.

Also I have read the S3 can not charge over a rate of .9 amps. And I have read otherwise. So many different values out there.
 
1) USB 2.0 ports can't supply more than 0.1 Amps. USB 3.0 ports can't supply more than 0.9 Amps. That may be where you got your 0.9 Amps figure.

2) The phone will draw what it's designed to draw, as long as the charger can supply that much current. It won't draw more. So if your phone is designed to draw 0.7 Amps, and you plug it into a 50 Amp charger, it'll draw 0.7 Amps.

3) The amount of current a cable can handle depends on the insulation. Wires increase temperature when current is flowing through them. If the insulation can handle 600 degrees C, the wire can handle a lot more current than the same size wire with insulation that melts at 40 degrees C.

When current flows through a wire, voltage is dropped across the length of the wire. (Which is what produces the heat - current flowing times voltage dropped equals Watts consumed in heating the wire.) As long as the insulation doesn't get too soft, and the voltage at the phone end of the cable is close to 5 volts, everything is fine. (Any wire - not just your phone charger cable, any wire - that's warm to the touch is carrying more current than it should, unless it has special high temperature insulation. The same holds true of wall outlets - the wall around the outlet should never get warm to the touch.)
 
I thought USB 2.0 could do .5 amps. Either way, the rest is correct. But do you know if the cable that Samsung supplies will handle 2 amps? Or could it possibly be the limiting factor?
And do you actually know the specifications for max amp draw on the dual core S3's?
I realize the whole "phones draw what they can/need" but what CAN these phones actually draw, lol?
I appreciate the response, anyways.

EDIT: well according to research on forums, which isn't always right, people seem to believe most modern USB cables can support 2 amps. I just wanted to make sure I'm getting the most out of my charging setup.
 
I don't know how many amps the S3 will take, but I do know that when I use my chargers/cables from my now defunct HP Touchpad and my N7, my S3 charges significantly faster than with the OEM or other phone charger/cables that I have lying around.
 
Well I don't think their is one factual piece of information out there about max amperage draw from the S3...
So using Battery Monitor Widget and monitoring amps used during the phone's sleep and adding that to the max amount of amps it shows me charging on average, I have came to a rough conclusion that the S3 can draw up to 1.2 amps, max.
Using the same method, I also think that my Galaxy Centura can draw up to .8 amps.
I really wish the S3 could pull more for a faster charge.
 
Yes, no harm. Most people's S3 came with a 1.0a charger but mine came with a 0.7a charger, so I would assume it is safe. It will charge slower, most noticeably when you are using it. If you play a demanding 3D game while using a .7a charger, you may not gain any battery percentage. I tend to use 800-900 mah during Real Racing 3, for example.
 
Omg I have screwed up. I have two Samsung chargers. One from my S3, the other from my Centura. They look 100% identical, even the printing on them. It so happens that one says .7a and the other is 1.0a. I apologize for that mistake. I must have gotten them mixed up at some point. I have been using the .7a charger for a couple of months. Still, I have an Anker dual port wall charger, one at 2.1a and the other rated at 1.5a. I still keep having the same findings when trying to estimate how much the S3 can draw. It still appears I can't take in more than 1.2a.
 
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