Garage control via NC relay?

[pgray007]

I'm considering automating my garages, and am relatively new to HAI after a few years with an Elk panel in our old house.
 
We have an Overhead Door co. garage opener that appears to operate via a normally closed switch. I have Cat5 to the openers; am I correct in my assumption that I can wire an HAI output to the Cat5, connect that to an Elk relay using the NC terminals, then trigger the output in automation to open and close the door?
 
With Elk I would have gone right from the panel so I'm new to using relays and want to validate my thinking.

 

[gatchel]

Typically you would use a N.O. dry contact not N.C.
 
Is this a commercial opener?
 
If they really are NC contacts in the GDO controller you would need to series in the relay not parallel as with a NO contact.

 

[rsw686]

Are you sure your opener requires NC? Usually shorting the wires will activate the opener, which would require the NO contacts. I used the HAI four relay module. The Elk relay should work as well. With programming I toggle the output on for 1 second.

http://www.leviton.com/OA_HTML/ProductDetail.jsp?partnumber=10A07-1&section=60582&minisite=10251

 

[ano]

HAI sells a bank of 4 or 8 relays that fit nicely in the HAI box. There really isn't a reason to use an external relay.  Each relay has a NO and a NC contact, so your choice. Cat5 will work fine to the openers.

 

[pgray007]

Typically you would use a N.O. dry contact not N.C.
 
Is this a commercial opener?
 
If they really are NC contacts in the GDO controller you would need to series in the relay not parallel as with a NO contact.

 
This is a home opener, and unlike past openers I've had there's polarity to the buttons (i.e. the opener has a + and - terminal rather than the usual "Whatever" terminals, and the buttons for the opener are illuminated, hence my theory on them being NC.
 
I'm writing this from memory and haven't played with the opener for a few days, but when I was up there and tried patching to the opener in the hopes I could control it without a relay, the opener triggered and the garage started moving as soon as I disrupted the wires that were in there. I haven't been able to find any specs on this particular opener, but I'm hoping its straightforward.

 

[az1324]

A lot of the newer openers use more complicated schemes to provide more than a single button control over 2 wires so you may have to attach your relay at the wall interface. 

 

[tmbrown97]

Further, even though many are compatible with smart panels at the wall button location, most can still usually be shorted to cause open/close.  At my last couple houses, I've yanked the smart panels in favor of plain ol' buttons so as not to have any interference with my automation.

 

[jharrell]

Typically it is AC using two diodes to allow three button over two wire. Full short is usually the main opener button, shorting just one of the phases does the other two functions(lock or light).
 
I use an HAI relay in parallel to the main button with NO and have a soft button setup that closes the relay for 2 seconds to operate the door. Has worked flawlessly for years and worked through replacing the openers with new ones (Chamberlain brand).

 

[pgray007]

Further, even though many are compatible with smart panels at the wall button location, most can still usually be shorted to cause open/close.  At my last couple houses, I've yanked the smart panels in favor of plain ol' buttons so as not to have any interference with my automation.

 
That seems to have been the ticket. I tried with the relay wired in series and NC and could get the opener light to blink, but once I put the relay in parallel in an NO configuration it works like a champ.
 
I think my wife did get a bit tired of me giggling each time I closed and opened the garage from my phone, strictly for testing purposes of course!