r314bd
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I bought a new power adapter and want to make sure it's charging at the current it advertises. Any apps that will let me see this?
That's not always accurate. This adapter for example says it outputs 2.1 amps when in fact it only outputs 500-700mA.Turn the adapter over and read the output printed on it.
Could use a Kill-a-Watt.
The kill o watt is reporting ac amperage. That would need to converted to amperage.
Thanks, wcjeep!
"In order to convert AC Amps to DC Amps, all you need to do is multiply the amperage by 10."
- Converting DC & AC Appliance Usage Into Amp Hours - Solar RV Panels
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That's not always accurate. This adapter for example says it outputs 2.1 amps when in fact it only outputs 500-700mA.
Good question, and for that particular charger, I don't know how that reviewer arrived at their conclusions. However, for this charger, the data seems to jive with what SGDM1 was saying. Charging over USB is apparently not as straight forward as one might think, since the base spec is only 500 mA and various handshakes need to take place in order for a device to determine that the particular charger it's hooked to will be able to supply more current without damaging it.
To answer your question about measuring current, yeah, that's pretty much the only way. You can also play some tricks by splicing in a small value resistor in series with the load and using a voltmeter to measure the voltage drop across it. Since V=IR, you can determine the current by dividing the measured voltage by the resistance.