I picked four of these up for testing with custom-built lock boxes. They aren't expensive for what they are, but the shipping was ridiculous! Originally I was going to buy two, but the shipping cost more than the sub-total!
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High-quality electric solenoid lock (https://www.dfrobot.com/product-1856.html) with durable steel parts. Features signal feedback, IoT compatibility, and operates at 9-12V DC.
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My order finally arrived today via UPS.
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One of these modules is slated for testing ASAP. I need to go over the specifications for these modules before I decide how I am going to drive them. I'm not really a fan of the application example from the DFRobot website (https://www.dfrobot.com/product-1856.html?srsltid=AfmBOoqktICSzmhQ31BjY6YTexEVD-imlpkVGGVIy3tCR-rn6iXYnDES).
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This is what comes in each package. It connects directly to the power source as well as to the control circuit.
Are you planning on putting these on your house's doors? Will this be part of your home control security system?
Quote from: granz on Sep 17, 2025, 07:23 AMAre you planning on putting these on your house's doors? Will this be part of your home control security system?
While these are pretty solid units, for my purposes they're intended for a lock-box and / or access door (non-human). When these unlock, they sort of eject the metal loop. The metal loop must be pressed back into the latch to lock it again. So in a way these work similar to the Amazon lockers in that the door opens itself, then must be manually closed.
Quote from: granz on Sep 17, 2025, 07:23 AMAre you planning on putting these on your house's doors? Will this be part of your home control security system?
I was a little confused at first about the actual operation of these latches, but now that I've had time to examine things a little closer, it's much more clear. Essentially you energize the "coil" for ~1 second to unlatch the lock. The other wire that I initially thought was a trigger, is actually a sensor that lets you know if the latch is in the locked / unlocked position.
The caveat is that you do need either a relay or FET (with flyback diode) to control the coil. In the DFRobot example they're using this relay (https://www.dfrobot.com/product-64.html).
Quote from: Chris Savage on Oct 13, 2025, 05:55 PMQuote from: granz on Sep 17, 2025, 07:23 AMAre you planning on putting these on your house's doors? Will this be part of your home control security system?
I was a little confused at first about the actual operation of these latches, but now that I've had time to examine things a little closer, it's much more clear. Essentially you energize the "coil" for ~1 second to unlatch the lock. The other wire that I initially thought was a trigger, is actually a sensor that lets you know if the latch is in the locked / unlocked position.
The caveat is that you do need either a relay or FET (with flyback diode) to control the coil. In the DFRobot example they're using this relay (https://www.dfrobot.com/product-64.html).
Make it open like this!!!
Quote from: JKnightandKARR on Oct 13, 2025, 11:16 PMMake it open like this!!!
Now that seems a little extreme! :P
Quote from: JKnightandKARR on Oct 13, 2025, 11:16 PMMake it open like this!!!
Wow, Chris, I did not realize that you lived in outer space! It must be rough having Borgs at your door - worse than sales people wanting to change you utility companies, I would think. ;D
Quote from: granz on Oct 14, 2025, 07:51 AMWow, Chris, I did not realize that you lived in outer space! It must be rough having Borgs at your door - worse than sales people wanting to change you utility companies, I would think. ;D
Borg are like the cockroaches of the galaxy. But, as for the latches, as soon as I decide what I will use to switch the coil, I will construct a lockbox that utilizes it. Years ago I wanted to build a reverse geocache, but I doubt I will do that now. The current concept is to use an RFID Reader to pop the box open.
Quote from: Chris Savage on Oct 14, 2025, 09:22 AMBorg are like the cockroaches of the galaxy.
Nah, that honor belongs to:
;D
Quote from: granz on Oct 14, 2025, 02:59 PMNah, that honor belongs to: ;D
That was a great episode though. ;)
Quote from: Chris Savage on Oct 13, 2025, 11:42 PMQuote from: JKnightandKARR on Oct 13, 2025, 11:16 PMMake it open like this!!!
Now that seems a little extreme! :P
That depends... lol but it would be interesting. lol
Quote from: Chris Savage on Oct 14, 2025, 03:52 PMQuote from: granz on Oct 14, 2025, 02:59 PMNah, that honor belongs to: ;D
That was a great episode though. ;)
So THAT'S where the Radroaches in Fallout came from! lol
Quote from: JKnightandKARR on Oct 14, 2025, 09:11 PMSo THAT'S where the Radroaches in Fallout came from! lol
What he posted was a video from Stargate: SG-1 where the replicators took over Apophis' ship and SG-1 was sabotaging it to crash into the planet. But, what's important to know is that, in the Stargate universe, the most advanced "living" race was unable to defeat the replicators. They were a scourge on multiple universes and the cause of the extinction of the race that is responsible for their creation.
I say it that was, because one person from that race created an android child, who in turn created a replicator as a toy, then lost control of her emotions causing them to go haywire, replicate and kill everyone. During the time in that clip the replicators are out of control just trying to replicate and expand.
Quote from: Chris Savage on Oct 15, 2025, 09:44 AMQuote from: JKnightandKARR on Oct 14, 2025, 09:11 PMSo THAT'S where the Radroaches in Fallout came from! lol
What he posted was a video from Stargate: SG-1 where the replicators took over Apophis' ship and SG-1 was sabotaging it to crash into the planet. But, what's important to know is that, in the Stargate universe, the most advanced "living" race was unable to defeat the replicators. They were a scourge on multiple universes and the cause of the extinction of the race that is responsible for their creation.
I say it that was, because one person from that race created an android child, who in turn created a replicator as a toy, then lost control of her emotions causing them to go haywire, replicate and kill everyone. During the time in that clip the replicators are out of control just trying to replicate and expand.
I saw that link above, but reminds me of these annoying things.. lol
Quote from: JKnightandKARR on Oct 15, 2025, 11:48 AMI saw that link above, but reminds me of these annoying things.. lol
I'm having flashbacks to the movie, Damnation Alley (https://www.imdb.com/title/tt0075909/?ref_=ext_shr_lnk) from 1977!
Specifically, this scene! :o
Quote from: Chris Savage on Oct 15, 2025, 12:03 PMQuote from: JKnightandKARR on Oct 15, 2025, 11:48 AMI saw that link above, but reminds me of these annoying things.. lol
I'm having flashbacks to the movie, Damnation Alley (https://www.imdb.com/title/tt0075909/?ref_=ext_shr_lnk) from 1977!
Specifically, this scene! :o
It's Fallout with bugs vs the Scorched n Ghouls. Lol
Quote from: JKnightandKARR on Oct 15, 2025, 04:32 PMIt's Fallout with bugs vs the Scorched n Ghouls. Lol
This movie IS post-apocalypse, so yeah. Fits right into the "Fallout" theme, just from the 70s.
Quote from: Chris Savage on Oct 22, 2025, 12:50 PMQuote from: JKnightandKARR on Oct 15, 2025, 04:32 PMIt's Fallout with bugs vs the Scorched n Ghouls. Lol
This movie IS post-apocalypse, so yeah. Fits right into the "Fallout" theme, just from the 70s.
Cool, I just finished watching Fallout S1 on DVD last night.
Quote from: JKnightandKARR on Oct 22, 2025, 01:01 PMCool, I just finished watching Fallout S1 on DVD last night.
And here I thought we were talking about the video games! :o LOL
Back on the subject of these latches. I thought of another use for them in terms of kind of a reverse logic.
Many years ago (like 35+), we used to catch squirrels and pigeons using box traps, where the critter would go under the wooden box to get a treat and you would pull the rope, removing the stick that held the box up. Gravity would drop the box and you
usually caught your critter.
Once in a while the squirrels would either get hit by the box, or escape altogether. It occurred to me that you could use these latches to release a spring-loaded door that closes, rather than releasing a door to open. It might be usable in a situation where you're trying to live-catch a critter. Just a thought. What do y'all think?
Quote from: Chris Savage on Oct 22, 2025, 02:05 PMQuote from: JKnightandKARR on Oct 22, 2025, 01:01 PMCool, I just finished watching Fallout S1 on DVD last night.
And here I thought we were talking about the video games! :o LOL
Back on the subject of these latches. I thought of another use for them in terms of kind of a reverse logic.
Many years ago (like 35+), we used to catch squirrels and pigeons using box traps, where the critter would go under the wooden box to get a treat and you would pull the rope, removing the stick that held the box up. Gravity would drop the box and you usually caught your critter.
Once in a while the squirrels would either get hit by the box, or escape altogether. It occurred to me that you could use these latches to release a spring-loaded door that closes, rather than releasing a door to open. It might be usable in a situation where you're trying to live-catch a critter. Just a thought. What do y'all think?
That sounds viable option.
Quote from: granz on Sep 17, 2025, 07:23 AMAre you planning on putting these on your house's doors? Will this be part of your home control security system?
So, these were for testing for a customer application involving swiping an RFID tag to open a lockbox. As I started the project and testing of the locks, which I was supposed to go over with the customer, he stopped contacting me, and I don't think he's getting my email. So I am going to roll this into a new project, which I already tested, but for which I need your feedback.
Since I have four electronic latches, I decided to build a locker system with four lockers that can be remotely accessed, or via RFID Tag, Password or Smart Phone. The prototype is a wood panel with f doors, but I wanted to build an actual metal locker as a working demo. The current working title is, "Package Pick Up Smart Locker", but I was wondering if anyone had a better and / or more streamlined name.
Quote from: Chris Savage on Feb 19, 2026, 02:00 PMQuote from: granz on Sep 17, 2025, 07:23 AMAre you planning on putting these on your house's doors? Will this be part of your home control security system?
So, these were for testing for a customer application involving swiping an RFID tag to open a lockbox. As I started the project and testing of the locks, which I was supposed to go over with the customer, he stopped contacting me, and I don't think he's getting my email. So I am going to roll this into a new project, which I already tested, but for which I need your feedback.
Since I have four electronic latches, I decided to build a locker system with four lockers that can be remotely accessed, or via RFID Tag, Password or Smart Phone. The prototype is a wood panel with f doors, but I wanted to build an actual metal locker as a working demo.
This sounds like the kind of thing that you might have at a PSC (Postal Service Center, not quite a Post Office,) only more high tech. The PSC that I had in tech school was run by Active Duty Air Force personnel, and so was not a Post Office, but had Post Office-type boxes, and could take packages to mail out.
Quote from: Chris Savage on Feb 19, 2026, 02:00 PMThe current working title is, "Package Pick Up Smart Locker", but I was wondering if anyone had a better and / or more streamlined name.
I like that title, it may be a bit long, but gets the idea across. It sounds like something that you would use at an Amazon pick up center to get your packages.
Quote from: granz on Feb 19, 2026, 03:26 PMI like that title, it may be a bit long, but gets the idea across. It sounds like something that you would use at an Amazon pick up center to get your packages.
The Amazon lockers were what inspired this project. People think they're so high-tech, and Home Depot and other stores have similar lockers you can use for product pick up. The fact is, with relatively little hardware, you can make it so the locker can be opened via website request, Bluetooth interface from cell phone, RFID tag or type in a code on a keypad.
The current test code for password uses a (fake) order number, billing zip code and the last 4 digits of your phone number to open a locker door. I have a simple 4x20 LCD and 4x4 matrix keypad.
Quote from: Chris Savage on Feb 19, 2026, 04:07 PMQuote from: granz on Feb 19, 2026, 03:26 PMI like that title, it may be a bit long, but gets the idea across. It sounds like something that you would use at an Amazon pick up center to get your packages.
The Amazon lockers were what inspired this project. People think they're so high-tech, and Home Depot and other stores have similar lockers you can use for product pick up. The fact is, with relatively little hardware, you can make it so the locker can be opened via website request, Bluetooth interface from cell phone, RFID tag or type in a code on a keypad.
The current test code for password uses a (fake) order number, billing zip code and the last 4 digits of your phone number to open a locker door. I have a simple 4x20 LCD and 4x4 matrix keypad.
That sounds like it should do the job. I would even think that it would be good enough security for real-life work.
Quote from: granz on Feb 19, 2026, 04:29 PMThat sounds like it should do the job. I would even think that it would be good enough security for real-life work.
Yeah, once I have a metal cabinet, I wanted to add the code to TXT me each time a locker is accessed.
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I was thinking of something like this for the lockers. For the demo, I might be able to find something used locally via the FB marketplace.
The 12v version of their electronic latch (from the same site (https://www.dfrobot.com/product-1891.html)) looks interesting too. Maybe for interior doors in the house.. Oh! A new diet plan - lock on the pantry door!!
Quote from: doggiedoc on Feb 21, 2026, 08:44 AMOh! A new diet plan - lock on the pantry door!!
LOL, great, now I need to build one for myself. ;D
Quote from: doggiedoc on Feb 21, 2026, 08:44 AMThe 12v version of their electronic latch looks interesting too. Maybe for interior doors in the house.. Oh! A new diet plan - lock on the pantry door!!
Doc,
I did look at that one when I placed my original order, but the neat thing about the one I got is it forces the door open, which makes it immediately apparent which locker you've unlocked. You could do the same thing with the one you linked by adding a spring to the door, but for the lockers, the one I have works great.
I think the one you linked would be great for a previous project of mine that I haven't posted in a long time for security reasons. Are you familiar with
tactical furniture? I helped a buddy build a shelf that conceals a trap door underneath which drops down, revealing his pistol. He need only hold a knick-knack on the shelf in the right position and the solenoid releases the weigh of the shelf.
Quote from: Chris Savage on Feb 21, 2026, 05:53 PMHe need only hold a knick-knack on the shelf in the right position and the solenoid releases the weigh of the shelf.
Nice! Very James Bond.
Quote from: doggiedoc on Feb 21, 2026, 10:01 PMNice! Very James Bond.
Of course, you can buy furniture that's made for this purpose. It's all over the internet. But now that you reminded me about that other solenoid, I think I will go ahead and rebuild that old project with a few twists, including the solenoid you mentioned, which is a better choice than what I previously used. Thanks for bringing that up.