Home Page link

How do garage door sensors work ?

Home Repair - - If it ain't broken, don't fix it. Otherwise look here. 

Bookmark this page:  YahooMyWeb Yahoo!  Google Google  Windows Live Favorites Windows Live  del.icio.us del.icio.us  digg digg  Add to Netscape Netscape
Subject Author Date
How do garage door sensors work ? John65stang 11-28-2006
If you were  Registered and logged in, you could reply and use other advanced thread options
Posted by John65stang on November 28, 2006, 11:32 pm


What I need to know is how the "electronic eyes" work. Do they send a
signal back to the opener ? Are they just a voltage loop that is opened
when something crosses the beam ? I believe thay are powered by DC
voltage.

The reason I ask is I am trying to build a timing clock for a guy and his
soap box derby car, and he got a pair of sensors for us to use and timing
spots to start and stop the digital stop watch, I need to build.


Plumbing 468x60
Posted by Tony Hwang on November 29, 2006, 12:12 am


John65stang wrote:
> What I need to know is how the "electronic eyes" work. Do they send a
> signal back to the opener ? Are they just a voltage loop that is opened
> when something crosses the beam ? I believe thay are powered by DC
> voltage.
>
> The reason I ask is I am trying to build a timing clock for a guy and his
> soap box derby car, and he got a pair of sensors for us to use and timing
> spots to start and stop the digital stop watch, I need to build.
>
Hi,
Typically it is a IR emitter and sensor set up. If beam is interupted,
sensor generates signal. From this you can rig up anything you want.

Posted by on November 29, 2006, 10:03 am



Tony Hwang wrote:
> John65stang wrote:
> > What I need to know is how the "electronic eyes" work. Do they send a
> > signal back to the opener ? Are they just a voltage loop that is opened
> > when something crosses the beam ? I believe thay are powered by DC
> > voltage.
> >
> > The reason I ask is I am trying to build a timing clock for a guy and his
> > soap box derby car, and he got a pair of sensors for us to use and timing
> > spots to start and stop the digital stop watch, I need to build.
> >
> Hi,
> Typically it is a IR emitter and sensor set up. If beam is interupted,
> sensor generates signal. From this you can rig up anything you want.


Actually, it's the reverse, at least for the sensor itself. When light
energy hits the receiving sensor, it generates a voltage which is then
detected. If he wants to use what he has,he can use a VOM to measure
it, then rig up an apporpriate circuit. However, I'd check Radio
Shack, as they may have cheap kit or already built hobby type solutions
for this.


Posted by Rich on November 29, 2006, 7:48 am


Why don't you use a transponder setup for radio control car/boat/airplane
racing?
Here's one that is used for rc cars; http://www.rclapcounter.com/.

Rich
http://www.garagedoorsupply.com



> What I need to know is how the "electronic eyes" work. Do they send a
> signal back to the opener ? Are they just a voltage loop that is opened
> when something crosses the beam ? I believe thay are powered by DC
> voltage.
>
> The reason I ask is I am trying to build a timing clock for a guy and his
> soap box derby car, and he got a pair of sensors for us to use and timing
> spots to start and stop the digital stop watch, I need to build.
>



Posted by jmagerl on November 29, 2006, 9:37 am


Be aware that most photoelectric sensors work by pulsing the LED. They do
this to get a higher brightness out of it (example: 50% dutycycle at twice
the power). As such if you use it to try to measure time there will be a
certain "quantizing" error in your measurements. The ones I'm familiar with
worked from 60hZ to the hundreds of Hz region. Don't know if thats enough of
an error to influence a soapbox derby outcome. (Can a person holding a
stopwatch be more accurate than 1/60th of a second?)

THere are of course special analog sensors that are used for time critical
measurements but I doubt they would be used on a garage door.

> What I need to know is how the "electronic eyes" work. Do they send a
> signal back to the opener ? Are they just a voltage loop that is opened
> when something crosses the beam ? I believe thay are powered by DC
> voltage.
>
> The reason I ask is I am trying to build a timing clock for a guy and his
> soap box derby car, and he got a pair of sensors for us to use and timing
> spots to start and stop the digital stop watch, I need to build.
>



Similar ThreadsPosted
Garage door sensors losing power March 14, 2006, 2:06 am
Garage door opener - no juice to sensors January 4, 2007, 8:51 pm
Moisture in Sears garage door opener sensors. March 8, 2007, 6:55 am
Stud Sensors that Really Work August 12, 2007, 1:49 pm
Chamberlain/liftmaster garage door remotes don't work anymore February 17, 2007, 2:45 pm
Garage Door Spring Rips Garage Apart July 7, 2007, 2:30 pm
Broken garage door cable-need to close door September 13, 2006, 10:33 pm
Need an Anozira Door Systems Garage door panel April 12, 2007, 11:49 pm
painting the garage... what prep. work is required? July 6, 2005, 3:25 pm
How to Tell If a Replacement Door Will "Work" March 29, 2006, 5:55 pm

Contact Us | Privacy Policy

XML SitemapXML Sitemap