I have built a circuit that triggers a few relays like this one
This produces a lot of noise in the circuit and sends false impulses to arduino activating randomnly different inputs, making arduino do weird stuff.
I have done some research and found this product:
This will technically remove the issues, but I am not sure how to install it.
The specification of the product only sais:
When used, the two connectors of the module connect to two contacts of the relay,
or parallel with the thyristor, to avoid induced electromotive force damage the relay or thyristor.
here is a link: STUBBER
Not very clear which contacts of the relay I should connect it to? is it in paralel between gnd and vcc?
Or maybe between gnd and signal for each channel? or between signal and vcc for each channel? or in series on ground wire?... I am very confused.