Comment on Why is amperage more "obscure" than voltage (or watts)?
givesomefucks@lemmy.world 15 hours ago
Amps are the variable part of the equation…
There are there parts of the equation, every one being constant would make every electrical component binary. Either full power or no power.
That’s why we really only see variable amperage on battery charges to force a slower charge rate for the health of the batter. On something like a radio, you could think of the volume knob as amperage control. The more power, the louder the sound comes out of the speaker.
A steady amperage current would “lock” the volume at one setting forever.
666dollarfootlong@lemmy.world 15 hours ago
Oh right yea that makes sense, thanks!
givesomefucks@lemmy.world 14 hours ago
It’s been a minute since I learned electrical stuff, so I might be off on details.
Like maybe a pretty steady amperage from the cord and it’s regulated inside thru resistance or something more complicated?
But that’s the general gist of why not all parts of the equation can be static.
The advertised Wattage is also “max” it can use/produce.
Like a 850watt power supply can handle an 850 power watt draw, but if all the computer is doing is playing YouTube, it’s going to draw a lot less amps, and produce a lot less watts as a result. If it needs more watts, it “pull” more amps to make them
Steam turbines are actually self regulating because of this. The more power being used, the more amps are automatically produced. Once you spin it up it manages its own speed.
cecilkorik@lemmy.ca 14 hours ago
This is sort of true, within a narrow operating window and an idealized environment, but also pretty simplified. That sort of application of Ohm’s law only works according to the naive interpretation when you’re talking about ideal DC devices. In reality, inductance and capacitance become significant and muddy the waters a lot when you start getting into real power grids with huge inductive loads like motors and transformers all over them, and steam turbines trip and/or bypass all the time to avoid overload or overspeed.