[How-To] Build the ULTIMATE Garage Door Monitor

[BraveSirRobbin]

elcano;

I have an Elk M1 Gold here that I'm setting up for my friends house so I did some testing. I biased that ten turn Bourns 100 ohm potentiometer with 13 volts and connected it to channel 16 of the Elk M1 as shown in the schematic above (in the actual How-To post).

I then looked at the "Status" option in the ELK RP software which shows the actual voltage each of those zones is currently set at.

I set that channel 16 to a "Type 34, Analog Zone" then looked at it's status via that menu (far right end of that menu).

I then connected a multimeter so it measures voltage across zone 16 as well.

I then turned the potentiometer one rotation and noted the voltage displayed by the Elk 'Status' software and my multimeter. I plotted the results as shown below.


(Click on Picture for Full Sized Image)
Elk Pot Test Results

I think based on this test that the Elk M1 should work for this garage door monitor. Maybe someone from Elk can verify this as I performed the test very quickly.

One thing to note is that by biasing the potentiometer at 13 volts your wattage increased, but it is still below the rated two watts of the pot.

I could do some more testing, but will need some guidance as I'm not that familiar with the Elk yet. Should I use my.Elk software and HomeSeer to get the actual values from the Elk? What rules would I have to use for polling if any?

Also, your power supply must be able to handle 13/100 or 0.13 amps.

As far as your image, send me a PM and I'll attach it to your post.

Regards,

BSR

 

[markthomas]

I applaud you for an innovative solution and a nice writeup. However, I have to ask: why would anyone need to know the exact position of their door? I really only need three states: Up, down, or somewhere in-between. You can do this with two wide-gap magnetic contacts per door.

 

[BraveSirRobbin]

I applaud you for an innovative solution and a nice writeup. However, I have to ask: why would anyone need to know the exact position of their door? I really only need three states: Up, down, or somewhere in-between. You can do this with two wide-gap magnetic contacts per door.

As stated above, there are a lot more simple ways of monitoring your garage door's status if all you want are basic open, closed and as you stated in-between states. Many people have expressed an interest in knowing the exact state of their garage door though and are not satisfied with this lack of detail.

I also have basic magnetic contacts which monitor my garage door, but wanted some more detail. Since I already have an A-D board (as do many of our members in the form of the Elk M1 and Ocelot/SECU16) it just wasn't that hard to get this detail.

Again, this is the ADVANCED ULTIMATE method of monitoring your garage door's status. If you just want BASIC open/close status then this IS NOT a How-To for you! Just go get yourself some wide gap magnetic contacts and monitor your door that way!

 

[markthomas]

So the answer to my question is that you'd do it only if you want the ADVANCED ULTIMATE method, not because you have any practical applications in mind?

 

[electron]

It's just really nice to have, especially when you have a touchscreen environment. If you look behind the garage door application, you could use the same concept to measure i.e. the level of salt in your tank, and I am sure there are other things you could use this setup for.

 

[deranged]

The project is a lot cheaper and simpler if you have an ocelot and secu16. All you really need is the 10 turn pot and some resistors . I have half implemented this already, my problem is mounting the pot. I don't seem to have a nice easy spot as BSR did to connect to the garage door mechanism.

I tried a rubber wheel on the pot up against 1 of the pulleys, and it was just unreliable after a while. And it is at the bottom of the list so I have not looked at it since.

StevenE

 

[Guy Lavoie]

Again, this is the ADVANCED ULTIMATE method of monitoring your garage door's status. If you just want BASIC open/close status then this IS NOT a How-To for you! Just go get yourself some wide gap magnetic contacts and monitor your door that way!

Think of it as the Monster Garage...door.

As Sir Edmund Hillary would have replied: Because it was there!

 

[elcano]

One thing to note is that by biasing the potentiometer at 13 volts your wattage increased, but it is still below the rated two watts of the pot.

I dont think there is a practical limit in the resistance of the potentiometer. The advantage of higher resistances is that it consumes (and dissipates) less power. My 1500 Ohms potentiomeer would only consume 13v/1500Ohms = 0.08 Amps, which is better if you supply the power from the same M1 power supply.

 

[JKnox]

My garage door interior is sealed from the elements and we don't get much moisture here in Las Vegas. I don't think it would be a problem with this pot, but just can't give you a 100% yes on this.

Ah, Nevada. Nope, excess moisture is definitely not one of your problems. My garage, while attached, is not heated. So after the garage gets good and cold in the winter, you have condensation problems when warmer, rainy weather returns.

Can you post some pictures of your garage door's layout or maybe EMail them to me? I'm curious of your situation and it might help others as well. Send me a PM and I'll get you my Email addy if you wish!

Let's keep it in the post - maybe the info will help someone else. BTW, anybody who gets the urge can email me from the profile - I don't mind in the least.

Here are pictures of both the right and left side mounts:

And no, you can't contact the rotating shaft via the hole in the left bracket (within reason anyway).

Here's what I've got handy to use - liberated from an old HP inkjet:

Using this would require rigging two brackets + bearings (the donor used nylon sleeves that are long gone and weren't shaped properly anyway). Hmmm, it just hit me - I have two doors... I guess I'd have to cut this up, but I was hoping the multiple contact points would help keep the thing stable and working long term.

If you are into micro controllers you could always just mount a magnet on a rotating part, place the sensor in a location so it gets one closure (pulse) per revolution and maybe count the pulses. Of course keeping the position straight will be a problem.

Yeah, absolute position would be a pain to establish after power failure. You would pretty much have to do a full open/close cycle to recalibrate each time.

For me, this is still a mental exercise. At the moment I've got basic "door closed" functionality, and waaaay too many other projects ahead of this. But it's still fun to throw stuff around...

Jerry

 

[BraveSirRobbin]

Hi Jerry;

Man, I live for solving problems like this one! I love combined mechanical and electrical projects! Maybe try something like this:

I would try slotting a mounting hole for the pot (in the metal mounting strap or "l" bracket), then get a smaller rubber stopper that would fit inside a soft durometer roller blade wheel (I have plenty here if you need one) and mount the potentiometer's shaft to the roller blade wheel via the rubber stopper.

Then you mount this combination on top of the garage door pipe so the roller blade wheel makes good contact with the pipe (the wheel is in parallel with the pipe). The slot in the metal mounting strap will enable you to get a tight grip between the wheel and the pipe.

Now when the pipe turns it turns the wheel, which turns the pot.

What do you think?

BSR

 

[BraveSirRobbin]

One thing to note is that by biasing the potentiometer at 13 volts your wattage increased, but it is still below the rated two watts of the pot.

I dont think there is a practical limit in the resistance of the potentiometer. The advantage of higher resistances is that it consumes (and dissipates) less power. My 1500 Ohms potentiomeer would only consume 13v/1500Ohms = 0.08 Amps, which is better if you supply the power from the same M1 power supply.

I spoke with David (Elk's chief engineer) and he stated that the pull up resistor can be removed, but it is a surface mount and will require a solder iron for its removal.

I agree with you that if you are going to use the supplied Elk DC supply you need to use a potentiometer that will draw less current. You should still get an eight volt or so swing for the first six turns biasing with 13 volts or so (quick estimate).

 

[BraveSirRobbin]

Just wanted to add that I got my PH Anderson Analog to Digital Converter board working via TCP/IP using a Lantronix EPS1 print server and software which lets you set a virtual com port to a device with an IP address (attached to a network).

I want to thank Guy Lavoie for helping me get this working (during our Friday night chat session)!

So what this does is let you locate the Analog to Digital Converter anywhere that an ethernet connection exists (including wireless options).

I will do a separate How-To on this later.

 

[FrankMc]

Hi BSR

Great write up !!! and a nice simple solution as well....

Hows the garage door monitor performing now you have it installed for a while...???

Frank

 

[BraveSirRobbin]

Hows the garage door monitor performing now you have it installed for a while...

Just like the day I put it in. I recently tested it just to see if it still maintained the accuracy just a couple of weeks ago.

I like it because now that it is getting warmer out we "crack" the door and it's nice to see the (MainLobby) display correspond with the exact position of the garage door.

I also recently installed my X-10 Car Monitor (another How-To) in my wife's Expedition and now have a display which corresponds to the occupancy of both our vehicles (mine and hers, just mine, just hers, both away).

 

[Steve]

I also recently installed my X-10 Car Monitor (another How-To) in my wife's Expedition and now have a display which corresponds to the occupancy of both our vehicles (mine and hers, just mine, just hers, both away).

If both your cars are gone, who's there to see if the display is accurate?