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Jack in the Box style Timed Lid Latch Release


New Member
I’m trying to build a simple latch that can be set to release a springed lid (like a jack in the box) at a specific time everyday to feed our cat. I’m a complete newbie to basic electronics. I’ve got a spare smartplug that i’d like to connect to a 12v Solenoid latch. I’d schedule the smart plug to let power through for 1 minute to release the latch which I would then manually reset nightly. Will it work to wire the Solenoid directly to a 12 AC Adapter and then into the Smartplug (see photo)? Is there anything else I need to be thinking about.
Latch Release.jpg


Well-Known Member
Most Helpful Member
The overall plan is fine. The possible issue is AC vs. DC. IF both the adapter and the solenoid are rated for 12 VAC, then you should be ok. Note that with AC there is no power polarity at the load. In the photo it shows the power supply and solenoid with red and black wires. If your actual components are like this, it is *not* important that red goes to red and black to black.

Most of what people call an "AC adapter" in fact have a DC output, so check this carefully. If you post links to your actual parts, we can review them. Photos also work. The adapter will have either a label or a molded section with text. Photo that. The solenoid might have a similar label or stamping.



Well-Known Member
Most Helpful Member
That is a 12 V DC solenoid. You need an AC adapter with a 12 Vdc output capable of supplying at least 600 mA (0.6 A). This is a very common adapter for small wireless routers, network switches, etc. A computer store should have generic models for a few dollars. ebay certainly does. A computer repair shop probably has a box of spares left over from upgrades or dead stuff, and might just give you one. I do, and I would.



Active Member
I was about to answer, but I saw AnalogKid's posts and he pretty much covered it.

Very simple setup just do what he suggested and the rest is the enclosure.
Good luck!

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