I bought a used Pixel 3 android handset. I had on hand a usb3 "pass through" indicator that displays supplied watts as an integer value. It ranges between 3W and 7W with a "dumb" wall charger.

Is this "normal"? If not, should I blame the phone or the indicator? Do I need to setup a breadboard with a DMM for reliable results?

Thanks so much

Joe

 

The phone determines the rate of charge. The charger need only supply the correct charge voltage the phone controls everything else. I have no clue what you are using as a metering device for your USB line? Assuming a 5 volt supply I get 3 watts / 5 volts = 0.6 amps and 7 watts / 5 volts = 1.4 amps, neither is unusual. Again, no clue how accurate your measurements are or how efficient your phone charging is.

Ron

 

I'd expect the current would vary depending on the state of charge of the lithium cell, and what the phone is doing (display on or off, cpu and gpu activity). The charger should do something with the data lines to indicate whether it can supply more than the default 500 mA . See: http://curioussystem.com/2010/08/18/the-dirty-truth-about-usb-device-charging/

 

The phone determines the rate of charge. The charger need only supply the correct charge voltage the phone controls everything else. I have no clue what you are using as a metering device for your USB line? Assuming a 5 volt supply I get 3 watts / 5 volts = 0.6 amps and 7 watts / 5 volts = 1.4 amps, neither is unusual. Again, no clue how accurate your measurements are or how efficient your phone charging is.

Ron

I have no massive reason to trust the meter, I paid something like $10 for 4. I guess the most I can expect out of it is a notification of something going drastically wrong.

Thanks again

Joe