USB cables 2 wire or 4 wire help

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Mikeadoo
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Last seen: 6 months 3 weeks ago
Joined: 02/12/2017 - 22:27
Posts: 426
Location: Chesterfield, Michigan

I dont understand how two 12 watts chargers iPad and this Insignia can have different amps. iPad 2.1, Insignia 2.4….

Anyone else think its just a marketing thing, or if its actually possible? I have the Anker PoerPort+1 charger that claims 3A

Mike

flydiver
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Joined: 06/19/2013 - 19:16
Posts: 1286
Location: Seattle, WA

Without measurement you really have no good idea what is happening.
Input devices for the most part are designed to have a maximum current they will deal with (accept). You can provide more, but they won’t use it.
If the output device provides a lower current than the input device can accept, then the charge will proceed, but more slowly.
If you put a high resistance cable between that will also slow down the process.
You cannot depend on the specs printed on the power ports. The better the ‘brand name’ the more likely it’s accurate. But, verify. For instance I have some Belkins 110v plug extenders with USB charging that are pathetic.

Get a measuring device, minimally something like this: https://lygte-info.dk/review/usbMeter%20UNI-T%20UT658%20USB%20tester%20U...
I have 2 of them and for basic use they are fine.

If you want to step up to being able to measure resistance then you have to get something like the UM24C tester and a suitable resistor load like I mentioned previously.

Those are the devices I’m familiar with. There may be better or more suitable options that you can dig out of the review or people in this forum may suggest. But you need something.

To Air is Human, to Respire….Divine.

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