PWM-controlled triac - worst case scenario?

Circuit: PWM output pin --> optocoupler --> zero-crossing triac --> NEMA 5-15R receptacle.

For controlling things like AC lamps, pumps, motors, et cetera.

What happens if someone accidentally plugs in something less tolerant of a chopped-up AC waveform, say a 60" plasma television or a laptop? What would be the result? I would assume they just wouldn't work, but that could be a dangerous assumption*. :P

If this is in fact dangerous, is there any way to detect said appliances' misfortune, via heat or current draw or something, and feed it the full voltage? Or is the only option use neon orange outlet warning labelling and plug protectors and leave it end user responsibility?

Thanks in advance. -=-=-

*Dangerous assumption = destroy the device, start a fire, and burn down an entire highrise in '70s style, a homage to "The Towering Inferno"...

Don't put a PWM signal into a triac, there is no point. A triac will turn on when there is a pulse or voltage on it's gate and then not turn off until the voltage drops to zero. So unless you can synchronise your PWM to the mains, or slow it down so that it is in the same order of magnitude as a mains cycle there is no point it will look to be full on all the time. The PWM needs to be at a duty cycle of at least 400mS to be much good and then lights will flicker and you will probably screw up your plasma.

The only way to dim stuff with a triac is to use phase angle control, that delays any gate pulse for a time after the zero crossing and then fires the triac. Again this can screw up pulse mode power supplies and cause them to overheat to the extent of flames.

Triac dimming (actually ANY dimming) is VERY BAD for anything that is not a straight forward resistive load like an incandescent light bulb or certain types of motors. Putting a dimmer onto any sort of appliance or electronics device will usually destroy it, especially the newer devices like laptops or LCD TVs with switch-mode power supplies. At best, the device will suffer from being under powered and may overheat.

The reason for this is switch-mode power supplies draw more current to make up for the lower voltage. More current = more heat. Also the triac switching chops up the AC signal into a very sharp, noisy wave, that is too much for the device's built-in noise filtering. So it wreaks havoc on the power supply and the circuitry inside the device.

It's usually pretty obvious when a dimmer device is in line with an outlet. The wall switch usually will have a knob or slider to change the dimming level, unless it's a home automation outlet with internal circuitry. But you can still usually identify those pretty easily.