Interfacing my baking oven lamp

Hi,
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?

Thanks!

A current sensor will work well. Make sure you pick one that can measure the small current of your light well (such a lamp can be as small as 1-2W, which would be about 5-10 mA).

Any optical solution would have to deal with the heat of the oven itself... that alone makes it a poor solution here :slight_smile:

I wouldn't recommend installing things inside an oven. The higher temperature there makes everything age fast, isolation gets fragile and kracks…..
The switching of the lamp is often done by a mechanical temperature sensor that makes a noticable "click" when it switches. Maybe that could be picked up from the outside?

I am confused why your concerned with the little light.

Presumably, when the “little light” turns off, the entire oven will have a significant power reduction.

Could you just put the AC current sensor on the main power cord to the appliance ?

mexxle:
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).

Or using an optocoupler?

Thanks!

Requirement contradicts itself.

Invasive...relay across the lamp
Non-invasive.... thermistor clamped to the exterior of oven internal case.

bluejets:
Requirement contradicts itself.

Invasive...relay across the lamp
Non-invasive.... thermistor clamped to the exterior of oven internal case.

OP asks for "invisible from the outside", not "invasive". A current sensor inside the oven's outer shell is invisible from the outside, and thus fits the requirement.

wvmarle:
OP asks for "invisible from the outside", not "invasive". A current sensor inside the oven's outer shell is invisible from the outside, and thus fits the requirement.

Op asked for ideas.
I...supplied one invasive solution and one none invasive solution.

Nothing to do with being invisible.