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Question

Does my cell phone wall charger use energy with no phone

Oct 6, 2011 10:27AM PDT

We all know to unplug our cell phone when it's fully charged. The charger has two ends. Does it use energy, when it's plugged into the wall, with no cell phone attached? I would think not, with nothing attached to draw current.

Discussion is locked

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Answer
Yes . . .
Oct 6, 2011 10:33AM PDT

Because a charger is a transformer with a primary coil (input), and a secondary coil (output), along with a rectifier to convert to DC, as long as it is plugged in, the primary coil is using energy.

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(NT) Sorry. You posted while I was typing.
Oct 6, 2011 10:38AM PDT
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Answer
Yes it does use energy when it is plugged into the wall
Oct 6, 2011 10:37AM PDT

The charger is a transformer that converts 110V AC or 240V AC into something like 6V DC. (Voltage may differ depending on the phone)