Detecting if AC appliance is powered

Grumpy_Mike:

  1. R1 don´t warm soo much, not need big dissipation

Yes but I think you need a bigger resistor than that, that is more power than just 0.125W.
Also note the voltage rating on C1.

I used a similar circuit on a set top box and the 0.25W resistor caught on fire when C1 failed.

I rear the temp of R1 with a optical termometer, and only warm 3 graus over ambient temp.
C1 fail, all circuit is protect by PS250X, but can use a bigger resistor, but in this case, only one R1 with 5W we will not have a fire.
Sorry, what voltage rating about are you talking?