This is a typical snubber circuit, consisting of 0.1?F in series with 100? :
Hi John, thank you very much for your reply. So, basically, my previous diode setup is for DC powered devices, right ? That’s why it will not work for AC powered circuit, I didn’t realize I made a big mistake before that. And can I ask that, is that only because I will have an inductive solenoid in the circuit, so I must have the snubber circuit for prevention of fly back voltage spike, right ? Because I don’t see people use it for bulb circuit with 230 Vac mains.
So, the snubber circuit will be connected in parallel to the solenoid ? Or before the load and between the hot and neutral power line like the drawing below ? I wonder if the snubber circuit is now a standard built-in part in the relay, so I only need to connect my load with the relay ?
Regarding to the relay, do you mean for a solid state relay which is not inductive , I don’t need a diode comparing to the electromagnetic relay which is inductive ? Although solid state relay has a longer life span, whats the benefit of the electromagnetic relay ?
The CONTACT SUPPRESSOR you suggested is rated for 250Vac, I noticed there are many AMPOHM suppressors with different rating, for example, 0.1Uf 47R or 0.22Uf 100R. How to select the right one for me, for example, my solenoid valve runs at 230V. Is that the larger the Uf and resistor, the safer I will be ?
And can I use Arduino’s 5V power to drive the relay if the relay has a rating from 3-32V DC ? Because I see many people tend to use an external 12V power to control the relay.
I watched a video, saying something about the Zero-crossing detector in circuit. I guess the zero-crossing detector is now a standard built-in part in the solid state relay so that I only need the relay ? Guess also true for the snubber circuit, also comes like a built-in part in the relay ?
Although you have shown your circuit built on a solder-less breadboard, this is totally unsuitable for use with mains voltages.
Thank you for the tip, although there are many videos on Youtube showing 230V bulb circuit on solder-less breadboard.