puakk

For most consumer electronics, there'll be a transformer within the adaptor that converts AC to DC. For the basic of the transformer, I'll just assume it's just a primary coil running the secondary coil.

So, the primary coil keeps on running at full power, as long as electricity is needed for the appliances.

Does this mean that even on standby mode, the adaptor still takes in full power from the power socket?
BTW, I determined that it keeps on running at full blast based on the idea that it's a separate circuit.

Since it is always creating magnetic field(which it must, since it's a coil), and creating even when no ones taps on it, it must run at full blast at all times.

Unless there's a way the primary circuit "automatically knows" nobody is tapping on it, it must be constantly making magnetic field at full blast.

billrussell42

"primary coil keeps on running at full power"
incorrect. wrong.

The secondary has a load, and that load draws current, which may be anywhere from zero up to the maximum load rating of the transformer, say 10 amps.

Depending on the turns ratio (say it is 10:1), that amount of current is supplied by the primary, multiplied by or divided by the turns ratio. In our example, this would be 1/10 th the secondary.

So if the secondary drew 10 amps, the primary would draw 1 amp from the wall socket. If the secondary drew 1 amp, the primary would draw 0.1 amp. And 0 amps would cause the primary to draw 0 amps from the wall socket (for an ideal transformer. Real world, there is a small current being drawn, how small depends on how good a transfomer it is)




edit, for your additional details.
I determined that it keeps on running at full blast based on the idea that it's a separate circuit.
wrong

Since it is always creating magnetic field (which it must, since it's a coil), and creating even when no ones taps on it, it must run at full blast at all times.
wrong, with no load, the magnetic field is much weaker.

Unless there's a way the primary circuit "automatically knows" nobody is tapping on it, it must be constantly making magnetic field at full blast.
wrong.