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Topic: Auto shut down AC Power (Read 1 time) previous topic - next topic


sjcomp


If you want to control the switch off from a microcontroller, simplest approach is to use an AC mains push button. Bypass the button with an SSR controlled by the microcontroller.

Could you elaborate? I have a push button and SSR in parallel. Push button does not preserve the state, right? AC will flow as long as the button is pressed. Let's assume the device is not powered and SSR is off.  So while AC is on (when I pressed the push button) I need to flip SSR so it allows AC as well. This means that I need something that works only when SSR is off, but the power is on. And then I need something to detect the press when the device is powered to unpower it.

This seems like something I should not be inventing. I know my Keurig coffee maker has this functionality (my wife will not forgive me if I take it apart :) ).

dc42

OK, so you want the same push button to serve as an off-switch as well as an on-switch. In that case I think it would be better to keep the device permanently powered using a low-standby-power PSU. That's probably what your coffee maker does.
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sjcomp


OK, so you want the same push button to serve as an off-switch as well as an on-switch. In that case I think it would be better to keep the device permanently powered using a low-standby-power PSU. That's probably what your coffee maker does.

I see. It seems that I can have my cake if I put more logic (as well as power adapter) on the branch with the push button. Thanks for the input.

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