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Need controller like garage door opener

  1. Sep 6, 2012 #1
    And maybe the answer is to simply buy garage door opener controllers and re-purpose them, but I bet someone here has a more elegant solution.

    Many of the things I want to make for my house tend to require behavior like an automatic garage door; meaning that the push of a button would open or close, lift or lower something, then stop in the open/closed, lifted/lowered position, and do the same in reverse when the button is again pushed.

    Most of the things I would do are for in the house, like opening and closing large shade louvers, lifting a panel to expose a TV (or lift the TV itself, yow!), etc. These things don't need the safety functions or the torque I imaging you need for a garage door but the functionality would be essentially the same.

    So the question is, are there off the shelf controllers for things like this? I haven't been able to find such a thing online but then I'm not sure what to call it.

    The next question will undoubtedly be sizing the right motor for the job, or what the best assembly is for the specific task, but I'll save that for subsequent posts if anyone here has ideas for me.

    Thanks in advance.
  2. jcsd
  3. Sep 7, 2012 #2
    I'm not aware of any type of pre-packaged torque device...the relm of usage is too broad for any one product.

    But one could certainly cobble together a generic approach to providing torque with a small gearmotor...there a hundreds of different types out there. The size & voltage required all depends on the torque & speed of motion desired: heavier load & faster motion == bigger size & more powerful. And expensive.

    Controls can be home-made affairs of bare-board controllers that you'd have to interface to the different voltages. I would be too lazy to do that, I'd probably just purchase any of the different types of simple industrial controllers knows collectively as a "Smart Relay."
  4. Sep 7, 2012 #3
    There is stuff like this available: http://www.newegg.com/Product/Produ...ords&cm_mmc=KNC-GoogleAdwords-_-pla-_-NA-_-NA
    Also X-10 I know makes dry-contact relay devices for remote drape controls, etc. like this: http://www.x10.com/pro/automation/pum01.htm [Broken]
    Look for 'linear actuators' on Grainger or McMaster-Carr to do the actual work. Maybe those will help a little...
    Last edited by a moderator: May 6, 2017
  5. Sep 11, 2012 #4
    Interesting. After looking around the web a bit I think the best way to go is the garage door logic board after all. They can be gotten for $10-15US on ebay and have all the functionality you would need.

    The question I have is this: When the door gets to its open or closed state, what is the mechanism that relays this info to the logic board that tells it to stop the motor and reverse direction the next time it's activated? Is it something in the motor that feeds back info? Or a switch that's tripped somewhere? Seems like something in the motor since they will stop, then reverse when encountering an obstruction, but I'm not sure.

    I could probably figure this out if I had access to an actual garage door, but I don't, surprisingly.

    The reason it matters is that I'll be cobbling this together from parts and would like to know what I'll need to buy beforehand.

    Thanks for the info!
  6. Sep 11, 2012 #5
    Pretty cool--I didn't know you could pick up a board so inexpensively. To answer your question, the autoreverse logic does seem to be built into the board, in that if I stop the door halfway up with the button, then push the button again it will reverse (and vice versa). With that said, however, there are also two limit switches mounted on the track to limit the maximum open and close distance. They each have a single wire (so the return path is the metal of the track itself) and wire into the terminal block of the unit. They each have a mounting screw that allows the switches to slide forward and backward on the track and these are adjusted experimentally to set proper operation.
    One thing that you're going to have to work around--all boards now have two inputs that would normally be connected to a photocell safety system which would mount at the base of the door; it is comprised of an infrared LED emitter on one side and a receiver on the other. If the beam is broken while the door is on the way down it autoreverses. The board will not function properly without at least thinking these devices are in place. It may go up normally, but to make it go down all the way without the photocell system connected one would have to hold the button down for the entire length of travel. They allow this so that if the photocell safety is not functioning, one can at least lower the door if they are monitoring it manually during its downward motion to make sure the door doesn't contact something/someone in the way.
    Obviously in your application this will have to be dealt with--and it can't be just jumped out as there is power for the emitter on the same two wires that the receiver sends the signal back on. If memory serves the emitter and receiver modules are hooked in parallel.
    A couple of other quirks--there are two torque potentiometers that limit the amount of torque the motor puts out during up travel and down travel to prevent damage to the door--I don't know if these are on the motherboard or a daughterboard, and whether they will have to be considered in your design. If they are triggered the door will either stop or reverse direction. Also, I'm unsure how it actually senses this motor torque--perhaps a current sensing pickup on one of the motor leads. Second, there is a timer built onto the board to sense if it is taking an abnormally long time to open or close the door. I think it's set for 30 seconds, and if the motor runs longer than that without hitting one of the limit switches the door also either stops or reverses. Can't remember which right now, but you need to keep that in mind if whatever you're building acts up.
    Anyway, hope that helps you out.
    Last edited: Sep 11, 2012
  7. Sep 11, 2012 #6
    Thanks Neurons, that helps a lot. You know way more about this than I would expect anyone to. You must have a garage.

    I was wondering about the infrared, but I assumed it could just be jumped or otherwise disabled. I hope it's that simple.

    I don't know much about motors, but I think some are internally switched such that a certain amount of resistance will cause it to do things like stop or reverse, etc. It may be this needs to happen on the logic board with all the extra safety requirements you have now, and might make for a more difficult adaptation.

    Might require a trial and error methodology unless I can find a detailed breakdown of the way these things actually operate.

    Thanks again!
  8. Sep 11, 2012 #7
    I'm not quite sure how you would get around the IR stuff. There are 2 screws, that are putting out some DC voltage to run the transmitter IR LED (plus the little LED on the side showing there is power) and then on the receiver there is another LED on the side that stays steady when the beam is okay and blinks on and off a couple times per second when the beam is broken. Because both units are in parallel on the same set of wires, a straight jumper is not the answer, nor is a straight open. It is using voltage levels somehow to determine if a) the units are installed and b) whether the beam is broken or not. Likely a small resistor sized to cause a certain voltage drop would fool the board into thinking the units are in place and the beam is unbroken. In fact, I just made a voltage measurement that will help you determine the right resistor value: When the units are hooked up and the beam is not broken, the voltage at the terminals is 11.35 VDC. When the beam is broken, the voltage is 12.75 VDC. So you need to find a resistor that will give you 11.35 volts when installed across the terminals of the board. A jumper would be 0 volts, and an open would be at least 12.75 and maybe higher. Start at 1K ohm and work down from there.

    I would be pretty sure there is a small toroid or current sensor around a motor lead that is picking that up for the board--this may possibly be replaced with a resistor as well, or perhaps just jumped or left open. I'm guessing--sorry but I'm not disassembling my opener to figure that one out! :)
    Last edited: Sep 11, 2012
  9. Sep 12, 2012 #8
    Thanks again Neurons for going to the trouble!

    I bet they all work the same way, or at least in a similar way. Which brand/model opener are you testing? I'll see if I can get the logic board for the same one and order that one.

    I'm guessing the same as you are about the feedback from the motor, and I bet if I just picked up the motor for the unit it all the leads would be there, probably a 5 or 6 wire harness and not much more complicated than plugging it in to the board.

    This would probably be very simple to figure out if I simply had a garage to play around with! I think I would be looked at askance however if I walked up to some strange house and asked to fiddle with their garage door.
  10. Sep 12, 2012 #9
    Yes, I would think as far as the safety system they're probably all about the same. On mine it's called Safe-T-Beam. I have around a ten year old Genie basic opener--H4000-07. It's new enough to be the Intellicode style of remote, and says Series II electronics. I was actually able to locate the manual online, as I just bought this house a few months ago and there were no manuals for anything. Turns out I was somewhat wrong on the torque thing--it isn't a current sensor, it's an RPM sensor. There is an 'opto-wheel' mounted on the back of the motor shaft. This is a round slotted disk with perhaps 12 or 15 slots. Then there is a three wire sensor (they call an 'opto-luctor') that shines a light through the disk to a photodiode on the other side and this counts pulses. (G and H) If the motor bogs down the pulse count slows and that either stops or reverses the motor. The sensor wiring is Red (Vcc), Green (ground or common), and Orange (signal). Don't ask me HOW you're going to manage that one! Here is a link to a (not great) copy of the guide I'm looking at. It's not the same place I found mine, but it will work. On page 12 see the schematic and the parts layout--should help.
    And I think you SHOULD go over and disassemble the neighbor's opener. It would be fun to see, at least until they called the police. :)
    Last edited: Sep 12, 2012
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