Solenoid On/Off

[ZachMTG]

Hi There,

I need a solenoid to function in a simple on/off capacity. 12v Power supply = retracted / Power supply off = in lock position. Do I need to purchase a transistor, diode, or Arduino to it to function with more than an on/off switch?

Thanks

[adafruit_support_bill]

You could control it directly with a simple switch. If you want to use an Arduino, you would need a transistor or MOSFET and a diode. This MOSFET will handle most solenoids: https://www.adafruit.com/search?q=mosfet&b=1

[ZachMTG]

Thank you!

[lyndon]

While you can control the solenoid directly with a switch, I'd put a small value capacitor or a flyback diode across the switch. The high voltage created when you switch the solenoid off can cause an arc that will pit the switch contacts over time, leading to unreliable behavior.