I would like to build a small device to make my baking oven "smart" and let me know, once the pre-heating is done.
My oven has a 230V lamp which lights up as long as the oven is pre-heating. Once the heating is done, the lamp turns off.
Do you have any suggestions how to let my Arduino know, if the lamp is on/off? The solution should not be optical, I don't want the device to be visible from the outside (no photoresistor on top of the lamp).
I though about something like an ACS712 current sensor to put in the line to the lamp? Or using an optocoupler?