elk rules and timing

[mikefamig]

My preference is to be wired directly to the Garage Door Opener (GDO) itself - the physical motor mechanism.

 
I haven't experimented with it myself but I have read that it won't work to hardwire the liftmaster 3800p motor directly to a momentary switch like a doorbell. The motor is activated by a signal from a smart switch. The switch displays the time and temp and I have read  that the switch just resets if you cross the two wires that go to the motor. 
 
Mike.

 

[drvnbysound]

I haven't experimented with it myself but I have read that it won't work to hardwire the liftmaster 3800p motor directly to a momentary switch like a doorbell. The motor is activated by a signal from a smart switch. The switch displays the time and temp and I have read  that the switch just resets if you cross the two wires that go to the motor. 
 
Mike.

 
Sounds like a replacement motor would be on order ;-)  
 
Kidding aside, I'm not familiar with that model, but have connected to GDO motors that have been installed between the early 90's and as late as a new construction home that was built a few months ago.

 

[tmbrown97]

Someday someone needs to do a little more research on this - because there's got to be an easy way to wire in at the motor head with the right inline resistor or something...  For me, I've just skipped the smart controls for now; most of these openers will work with the smart panels or a traditional contact closure button.  For my own house I just went back to the regular buttons and wired in at the head unit.
 
Another solution, though more costly, would be to wire into 3 separate compatible remotes... this would get rid of the delay that the single remote seems to encounter.  You'd still want a momentary delay of like a second or two just so they're not all transmitting at once.
 
And yet a 3rd option... Some time ago, Lou Apo did some hacking with a multichannel wireless relay... this could have the remote hacked wherever you have it now and the relay board over by the smart panels with the wires soldered into the correct locations on there - in place of running a wire to the three openers (assuming the buttons are grouped together somewhere).  http://cocoontech.com/forums/topic/19476-wireless-relay/
 
Or even a 4th option - depending on what features of the smart panel you need, possibly relocate them together somewhere over by the elk, and use a wireless stuck on the wall wherever they're currently mounted (door into the house?)...
 
But good job with the programming - you seem to have figured out the outputs and timing sequencing pretty well.

 

[mikefamig]

Thanks for all the suggestions and ideas. The doors are working well now and I'm happy with that. When I get a little time I'll play around with a volt ohm meter and see if I can tell what the "smart" switch is up to. 
 
W2P - yes I am starting to understand the rules language.Right now the three overhead doors are checked and then closed if necessary whenever the garage is armed away. The garage is automatically armed away at 8pm and also any time the house is armed away. Now I'm thinking about changing the 8pm rule to start checking at 8pm and not arm until  there is a lack of motion for 10 or 15 minutes. I was out there working when the rule executed at 8pm tonight and had to run to disarm it.
 
Fun stuff! I'm looking forward to start automating lighting. My wife had a neat idea. If there is a breach in the garage she wants to not only sound the alarm but also turn on bright lights and open all three overhead doors. If it's dark out it would be like pulling the thieves pants down. Then I'd lock the place down again a few minutes later.
 
Mike.

 

[mikefamig]

OK so I took a closer look at the wall mounted overhead door control today and there are two wires connected to it from the motor. The control has a backlit lcd and there is 15vdc measured across the two wire connections. Also according to Liftmaster, you need to use wireless remote controls if you want multiple switches.
 
So I removed the control from the wall and I took a chance and momentarily crossed the two wires that are connected to the control and the door did start going down. I then crossed the wires again for a second and the door reversed. Now you might think good, just connect the elk relay to the two wires and be done with it but I don't think that it would be a good idea. I don't like shorting the 15 volt power from the motor even though it did cause the motor to work the way I want it to. I'm concerned that crossing the motor's power supply output like that could damage the motor. I'm thinking that in normal operation the control sends a digital signal to activate the door.
 
Now I know that I can solder wires across the little micro switch on the pcb to simulate a button push with a finger but does anyone have any knowledge of this control and if it would be safe to just cross the wires that attach the control to the motor?
 
The motor is a Liftmaster 3800p jackshaft type opener
 
http://www.liftmaster.com/CatalogResourcesV3/en-us/shared/files/tucmanuals/114A3399.pdf
 
and the control I believe is a 378LM or similar (it's a couple of years old)
 
http://www.liftmaster.com/CatalogResourcesV3/en-us/shared/files/tucmanuals/114A3327.pdf
 
Mike.

 

[mikefamig]

FYI - I just answered my own question. I just got off the phone and it is ok to just cross the wires on the 3800 series motor. Unfortunately only two of my three doors have 3800 motors. My third door has a 3550 elite opener which uses MYQ technology and has an encrypted signal from teh wired wall control to the motor so you can not cross the wires.
 
Two out of three aint bad but it aint good enough either. I'll just have to stay with the wireless remote control hooked to the elk. Hope I saved someone else some time.
 
 
Mike.

 

[drvnbysound]

I have a single garage door opener - that motor is wired as you found yours to be. Shorting the two wires causes my door to open/close. I directly wired these to the OUT3 provided directly on the Elk panel and wrote a Task to activate that output for 1 second. I use various rules to activate the task.

 

[drvnbysound]

I don't like shorting the 15 volt power from the motor even though it did cause the motor to work the way I want it to. I'm concerned that crossing the motor's power supply output like that could damage the motor.

 
What do you think happens when you press the button on the switch? It shorts those wires the same way as you have done - the difference is that there is a momentary switch in line. You can use a meter to verify this. Remove the wiring from the switch as you did previously; test continunity across the terminals when you hold down the switch.

 

[mikefamig]

What do you think happens when you press the button on the switch? It shorts those wires the same way as you have done - the difference is that there is a momentary switch in line. You can use a meter to verify this. Remove the wiring from the switch as you did previously; test continunity across the terminals when you hold down the switch.

 
Being that there is a printed circuit board involved you can't know that. You are correct about the 3800 motor but my third door has a LM 3550 elite motor and you can't do that to it. Read my earlier post today.

 

[drvnbysound]

You are correct about teh 3800 motor but my third door has a LM 3550 elite motor and you can't do that to it. Read my earlier post today.

 
Sure. I saw that. Nothing more (that I know of) that you'd be able to do there.
 
However, if you directly wired the first two doors, you'd be able to avoid the timing delay that your wireless controller is requiring and would be able to close all 3 doors at once... correct? Not sure if this would be worth the effort, but that's a call that I can't make. I've yet to run into this and have been able to directly wire (3) different GDOs, and will be doing (3) more by the end of this week.

 

[drvnbysound]

Being that there is a printed circuit board involved you can't know that. You are correct about the 3800 motor but my third door has a LM 3550 elite motor and you can't do that to it. Read my earlier post today.

 
You can't test continunity across wire and switch terminals connected to a PCB?
 
What happens to the [switch] circuit when the button is held down for an extended period of time (e.g. 5 minutes)? Is that switch still providing a closed circuit?

 

 

[mikefamig]

What do you think happens when you press the button on the switch? It shorts those wires the same way as you have done - the difference is that there is a momentary switch in line. You can use a meter to verify this. Remove the wiring from the switch as you did previously; test continunity across the terminals when you hold down the switch.

I did as you suggested. I disconnected the control from the wall and put a continuity tester across the terminals and pressed the button  and as I suspected nothing happened. Understand that when you disconnect the control from the wall you remove it's power source. It stil may or may not just cross those terminals in normal operation but you can not assume that. There is a board full of IC's and components that you are ignoring and I hardly ever get away with that.
 
Mike.

 

[drvnbysound]

I did as you suggested. I disconnected the control from the wall and put a continuity tester across the terminals and pressed the button  and as I suspected nothing happened. Understand that when you disconnect the control from the wall you remmove it's power source. It stil may or may not just cross those terminals in normal operation but you can not assume that. There is a board full of IC's and components that you are ignoring and I hardly ever get away with that.
 
Mike.

 
Understood. I figured that would be step 1. I also found this to be the case with my GDO switch.
 
Next, would be to connect the wall switch back to the existing wiring (to provide the PCB with power, as you suggested) and test continunity at the GDO [motor] terminals, while the button is being pressed.
 
Yet another test would be to test across the momentary switch only... where you could also connect the Elk (OUT3) and "simulate" physically pressing the button.
 
As you've already found [by using the wireless controller only] - there are many ways to skin this cat...

 

[mikefamig]

I just thought of a definitive way to tell if it is ok to cross the wires or not. With the control connected to the system and running normally you can test each of the two wire terminal's voltage in reference to the system common. If one is high and one is low with the button un-depressed and they both go high with the button depressed and the high voltages are eqiual then you are good to cross the wires.
 
Mike.

 

[mikefamig]

 there are many ways to skin this cat...

That's what I love about troubleshooting.