Chicken Coop Door Opener

Thread Starter

flumes

Joined Jun 6, 2016
1
I have a 12 volt linear actuator that I am hoping to use to open/close a door in my chicken coop at certain times in the day.

The linear actuator has built in limits and operates at less than 5 amps, but I would rather use seperate limit switches to control the amount of stroke the actuator has.

I am thinking of using a 12V power supply connected to a digital timer to send power ( + - ) in the morning to open the door. I would then use a different timer to send power (- + ) in the evening to close the door.

Any ideas how I can make this work, (using relays and micro switches)?

Any help would be appreciated.

I will by beer :)
 

crutschow

Joined Mar 14, 2008
31,112
You could use a single sprinkler type timer (such as this) since they have more than one output.
Note that the output of these timers is typically 24Vac so the relay coils also needs to be 24Vac (example).
Here's a conceptual connection diagram for the relays and limit switches.

The timer output takes the place of the switch, with the relay coil returns going to the timer output instead of the motor power supply.

Edit: Note that relay contact protection from the inductive motor kick is not shown and should be added.
For that you should connect two diodes (1A or greater such as 1N400x) to each motor connection (4 diodes total), one V+ to motor (anode) and the other V- to motor (cathode).
 
Last edited:
Find a timer. Decide on a power supply for the timer.

Two SPDT Bosch Automotive style relays hooked up the right way (see power door lock wiring) will give you an OPEN//CLOSE relay.
The wiring method causes the motors to stop fast.
The limit switches basically would interrupt the respective OPEN/CLOSE coil.
For DC, you should use reverse biased diodes on the relay coils.

Now, you can turn these two OPEN/CLOSE signals into an ON=OPEN, OFF=CLOSED from your timer.

Would chickens prefer an autonomic timer? A timer that can turn on/off based a time before after sunset/sunrise?
 

crutschow

Joined Mar 14, 2008
31,112
How do you stop the door squishing a chicken?
Two things make that unlikely:
The door probably moves slowly enough that the chicken would naturally have plenty of time to get out of the way.
The door is normally closed after sundown to make sure they are all already back in the coop. You don't want to close the door with any still outside (where they can become a tasty meal for night-time predators).
 

GopherT

Joined Nov 23, 2012
8,012
If you use external limit switches you will have to teach your chickens not to mess all over them ;).
I would just use a current sense resistor and assume it is closed one enough current is drawn in each direction. I would be using a motor and toothed belt instead of a linear actuator.
 

splud

Joined Jun 30, 2013
37
If you use external limit switches you will have to teach your chickens not to mess all over them ;).
FTR, limit switches can be placed in the sides of the door frame on the side and ABOVE the opening and trigger on detents in edges of the door. This keeps them up and away from debris. The head of an old toothbrush or part of a paintbrush can be used as a brush near where the edge of the door runs into the track, knocking away any debris carried up by the door, so that is stays away from the switch.

I've constructed a couple of auto coop door openers, and used a small geared DC motor, operating it more as a regulator, with the door (a piece of galvanized sheetmetal with the bottom edge folded over so it isn't sharp) counterweighted. In such an arrangement, there is not much apparent weight to the door. Think of old-school double-hung windows.
 

crutschow

Joined Mar 14, 2008
31,112
Why is it that if you post a thread asking a question, you get people complaining and saying that there are already many posts on that subject, but when you go to those posts and comment they complain about bringing up old posts. Go figure.
They are telling you that to get more information.
If you have questions about those old posts then refer to them in your original post, otherwise it gets confusing.

And it's generally bad form to post in old threads, since some of the original posters may no longer be around.
 

crutschow

Joined Mar 14, 2008
31,112
Posting your questions on someone else's thread for your own interest is called hijacking a thread, and that's frowned upon here, so that's why you should start your own thread and reference all other threads of interest to your own thread.
That's less confusing for us, if not for you.
 

djsfantasi

Joined Apr 11, 2010
8,652
I don't see how it is more confusing to keep the information on a single thread than to be jumping back and forth between threads.
Plus I posted information on a thread that wasn't that old and it got move with NO warning. Now when you look at it I doesn't make any sense unless you go back and read the other thread, again that is way more confusing.
Because you may be unfamiliar to forums etiquette. Necroposting alerts the thread started that more information has been added to his post. But, s/he may no longer be active. So the information goes into a black hole.

Starting your own post is preferred. Because, it’s active and more current than something five years ago. It’s how this works.

Plus it doesn’t annoy current members. Hence “etiquette”!

If you want to preserve continuity, insert a web link to the original question. Even better, use the insert link function on the forum. Good not to annoy people who may have your answer.
 

ThePanMan

Joined Mar 13, 2020
520
Long time ago I had a bunch of actuators. Screw drive type. They ran on 24 VDC. Power the motor in one direction and it would extend to its limit. Reverse the power and it would contract. As for limiting motion would be to pick a location on the door so that you get the amount of operation you want without having to change any of the limits. Wondering if you could use something like that. And no, those have been gone a good 14 years now. I think they came out of an adjustable bed frame. So lots of power just in case that's needed.
 

Tonyr1084

Joined Sep 24, 2015
7,198
What comes to my mind is a tread mill incline motor. They're short stroked and have limitations. They operate (the ones I've seen) on 120 VAC. Those are also screw type.
 

ronsimpson

Joined Oct 7, 2019
2,520
actuators. Screw drive type. They ran on 24 VDC
I get them from old recliner chairs.
1588023843071.png
They come with a 24vdc supply and remote. (when you get them used) All have end stops that cut the power. Some have adjustments to set the end points. Most have about 1 foot of travel. If you get them new you can get almost any length.
1588023957190.png
 
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