Control 220V AC valve whit arduino via MOSFET

Other Hardware General Electronics
1

Can someone please draw me a simpl diagram of controlling a 220/230V 50Hz valve whit N channel MOSFET whit arduino output?(i dont wanna use relay).

I designe lots of electronic deices but this is my first encounter whit controlling high voltage AC loads and i alrady burned some mosfets and a USB port on my laptop :stuck_out_tongue: My biggest problem is how to get common ground so i can control transistor via arduino.

Thanks for any help.

2

MOSFETs don't work with AC.*

You also need to isolate** the Arduino (and yourself) from the high voltage. That means optical isolation or mechanical isolation (a relay). It's OK to have a common ground, but usually it's not necessary. And the AC side, there's probably an earth ground connection for the solenoid valve's body. Neither side of the solenoid's coil is grounded (there may be two hot wires or a hot & neutral).

(i dont wanna use relay).

Is a solid state relay OK? (That would be optical isolation.) You can drive a solid state relay directly from the Arduino, whereas a mechanical relay usually requires a driver.

It's possible to build your own solid state relay with a special opto-isolator and a TRIAC, but as you've found out, it's easy to fry stuff (or yourself) when working with power line voltage. So, I wouldn't recommend that for a beginner.

  • There are ways of getting around this, such as rectifying the AC, or using a pair of MOSFETs (one handing the current in each direction) but it's not something I'd try unless I had a really good reason not to use a solid-state relay.

** Isolation means there should be NO electrical connection (no continuity) between the AC circuit and the low-voltage circuit.