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Slow and unsafe charging with unqualified charging cables - Explained

Why is my charging so slow?

An unqualified charging cable could have a dramatic voltage drop. For example, if your charging cable's impedance is 500mΩ, which many low quality cables do - it will have 0.5v drop @1A charging current, 1A x 0.5Ω=0.5v. This means you will only get 4.5v at the phone end even though your charger provides 5v. Most smart phones won't even charge in this case. This explains a lot of charging issues that we have.

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FYI, the above calculation is following Ohm's law as shown here:

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Why is this a problem?

As we all know, charging current is now getting higher and higher due to accelerated processors and high RAM demands of smart devices. Many devices are even charged at 2A or above, such tablets or even phablets.

The quality of charging cables has become critical nowadays, especially in an age of exploding Galaxy Note 7s. Take the given example above, it will have 1v drop if you are charging at 2A current which leads to only 4v to the device end. Beside the potential safety issues you may have, there will be certainly no charging at this low voltage for smart devices - especially those that require the higher 2A currents.

Where is the voltage drop going?

It's mostly transforming into heat as power dissipation which can make charging become a hazard and extremely dangerous. It can lead to overheating, fires, explosions, or even blow up your device. Invariably in such circumstances, it will destroy your phone's battery. This is the reason why your phone may no longer hold a charge as well as it used to - its battery lifespan will have decreased.

The above description might not be easy to many people as it requires an electronic background to understand. Usually it requires proper tools and professional equipment to help measure the impedance of a cable.

The simple solution

qualMeter is the first of its kind. Unlike anything on the market, it's a compact, pocketable device designed to analyze the impedance of a charging cable with easy and intuitive reading results - especially for non-tech people.