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Cadman-LT
User Rank
Platinum
Occupancy Sensors
Cadman-LT   7/3/2012 11:11:15 AM
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Yeah, they are called occupancy sensors. They are put in places such as restorooms. I thought someone would have called me out on that. 

Tool_maker
User Rank
Platinum
Re: Off question
Tool_maker   6/20/2012 12:53:52 PM
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I am sure it is something you can buy off the shelf at Home Depot or Lowe's.

Cadman-LT
User Rank
Platinum
Re: Off question
Cadman-LT   6/20/2012 8:48:56 AM
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I still want to do it...just looking for the cheapest way. So it was a joke wrapped up in a true question...kinda. Any advice on the cheapest way is cool with me.

Cadman-LT
User Rank
Platinum
Re: Off question
Cadman-LT   6/20/2012 8:45:30 AM
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Yeah, it was just a joke. Seeing if anyone was paying attention. :)

Tool_maker
User Rank
Platinum
Re: Off question
Tool_maker   6/15/2012 10:10:48 AM
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I am sure you are kidding as many public restrooms already use such a system. As for the pet door, we have trained our Border Collie to ring a bell tethered to the doorknob when she needs/wants to go out. I am sure many dogs could be trained to activate the pet door in a like manner. I guess a timer could be utilized to lock it after a reasonable amount of time and a separate opener on the outside.

Cadman-LT
User Rank
Platinum
Off question
Cadman-LT   6/11/2012 6:00:16 PM
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This just made me think of something that one of you maybe can answer. Do they make sensors for rooms so when you walk in the lights turn on and off when you leave? Light switches just seem so outdated...lol

William K.
User Rank
Platinum
dog and cat door.
William K.   6/7/2012 9:19:26 PM
NO RATINGS
I don't think that any "innocent child" would be attempting to enter a window that far above the ground, or, for that matter, why anyone innocent would be attempting to climb in a window. Anybody living in that house would already know about the connection and avoid the problem. OF course, an alternative to a direct line connection would be an electric fence charger, one of those used to keep cows in place. OF course, you make the assertion that any ac line shock is always fatal, which is incorrect. They may be potentially fatal, but the vast majority of 120 volt AC line shocks are not fatal. We only hear about the very few ones that are, we get no reports about shocks that are merely painful. 

The original description was of a cat door placed quite a distance above the ground at a height that a child could not possibly reach. Most innocent children don't jump up that high. In fact, most innocent children are not six geet tall, as I recall.

As for live wires, I had to take some extreme steps a while back when the bulbs from my post light were being stolen repeatedly. I doubt very much that it was an innocent child taking out the glass and stealing the bulbs. 

hydrogent
User Rank
Iron
Re: Automating a dog door, or cat door
hydrogent   6/7/2012 12:33:59 PM
NO RATINGS
William, Please tell us you are kidding about electrifying a pet door! It sounds like fun, but what about the innocent child that happens by & tries to follow the kitty? The charge would be murder.

Regarding the magnet collar sensor or other automatic lock-out that others mentioned, if we did not have such we would have neighbor cats & raccoons in our house

William K.
User Rank
Platinum
Automated pet doors
William K.   6/6/2012 10:19:16 PM
NO RATINGS
The successful doors that I have seen did not use a solenoid to open the door. Not only is the force to displacement curve the opposite of what is required, but also any solenoid able to do the job will draw way too much current. The commercial units that I saw used a small motor to raise the door, which does a far better job and consumes less power.

robatnorcross
User Rank
Gold
Re: Automating a dog door, or cat door
robatnorcross   6/6/2012 6:21:21 PM
NO RATINGS
My families dog (Charlie) invented this decades ago. He trained the humans in the house to come and open the door at his command. He stood by the door and barked once. If we didn't respond in a timely manner he barked twice (you get the idea. When he wanted back in he did exactly the same thing.

May be people should just get smarter pets.

If WE were as smart as he was we would have taken out a patent.

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