Activate Induction Hob by Arduino

Thread Starter


Joined Apr 14, 2016

This is my first question in this forum, I hope you guys can help me figure out a solution to my problem. I´ve spent a few days trying to solve this and could not find a stable solution.

What I am trying to accomplish is a Induction Hob controlled by Arduino. I've already did that with a portable Induction Hob and a Bechoff PLC: I soldered a 100 nFarad capacitor to the capacitive buttons and connected it to a relay that shorts it to the Ground, simulating the finger pressing in the button. It works pretty well, and I could do some automatic programs for my hob, It will turn on the hob, select the function and control the power (by "pressing" the + and - power button according to the feedback from a temperature sensor) and turn off at the end.
Now I am trying to do the same with a more powerful Induction Cooker. I am using an EGO interface and Power Module. This is the control interface of my Induction Cooker, which controls the Power Module:

So, what I want to do is basically the same: Connect each button to a relay which will be controlled by an Arduino, simulating the finger pressing. Below each those black pads there is a layer covered by solder, which I believe will sense the change in the capacitance caused by the finger pressing.

I tried several different approaches: Connect a capacitor to the layer and then short it to the Ground (Basically what I did in the other project) and it didn't work. Short the capacitor to VCC, no success. Short directly to GND or VCC, and it doesn't work.
I tried also to add some resistors and it didn't work as well.

It seems that the black pads have a resistance of about 1 MOhm. I tried to glue a wire to it and short it to GND or VCC, and it doesn't work, but if I touch the wire with my finger it will work.

What could be done to simulate the finger pressing with a relay?
Sometimes it worked, but it was not stable: If the wire was bended the other way it would not work anymore.

Thank you very much for taking your time to help me with my project!