heating elements

Nope, that would cost too much.

Just on/off cycles. cycles that are in seconds of each time.

Some of them are so cheap, they just use bimetal temperature switches

jamie.

In a way - they're usually controlled by a thermostat, which turns off the power at one temp, and back on again at another, lower temp.

Sort of like PWM whose pulse width is measured in hours.

Hope This Helps! Rich

"Rich Grise is Wrong Again "

For coils and hot plates, power control is by an adjustable thermal switch that cycles on and off at a rate determined by its own self heating and the setting on the dial.

..... Phil

yes, at a very low frequency. typically 1Hz or less.

Phil Allison:

Why? Isn't what you just described?

Yeah, but that's Phil.

Admittedly, I could have said "minutes" instead of "hours," but that all depends on the application.

Cheers! Rich

"F. Bertolazzi"

As even a f****it like you should have picked.

.... Phil

You lying f****it.

.... Phil

Phil Allison:

Hey, wait a minute...