Re: Garage Door Opener keypad recommendations

[George <no.geodosch.spam@xxxxxxxxx>]

On Sat, 20 Nov 2010 21:49:14 -0800, Jim thoughfully wrote:

> On Nov 20, 4:08Â pm, tourman <robercampb...@xxxxxxxxx> wrote:
>>
>> > What's wrong with that is that a roller ball will fail and you don't
>> > know it. The mag switch fails open.
>>
>> > I'd agree with you on the inherent problems if you're using standard
>> > magnet recessed contacts. But now ..... with the newer Rare Earth
>> > magnets, there's no problem at all with the issues you cited. You
>> > just have to be careful the Rare Earth magnets don't pull the
>> > fillings out of your teeth.
>>
>> RHC: Yeah, any roller ball contacts that failed were usually determined
>> by a trouble call where the client opened the door and a motion
>> triggered the alarm. Customers don't check their alarm systems
>> whatsoever, and the don't notice things until they have an open zone or
>> one that triggers an alarm.
>>
>> Rare earth magnets have definately improved things overall. Now you do
>> have a bit more than just opening the door a crack before the zone
>> opens. I still prefer the tolerance of a roller ball though, and as
>> long as they remain as trouble free as I have found them to date, I'll
>> likely stick with them when the frame of the door allows it. One minor
>> side benefit - when a client changes only the door and not the frame,
>> it's one less service call. Nor do they cause another problem I've seen
>> with magnetic contacts where the magnet ends up falling out of the door
>> on occasion.
>>
>> Bottom line, I stock all sorts, colours and lengths of either magnetic
>> and roller ball. Sometimes you get out there, and you just don't know
>> what you'll find....
>>
>> When I first started installing, I worked for a company here that has
>> long since disappeared, and I have a bushel basket full of assorted
>> contacts of all different types, colours and connecting ends that I can
>> draw on when I find a weird situation that I have to deal with.-
>
>
> Of course we can both cite different experiences. With regard to your
> setting off the motion detector as the indication that the door switch
> isn't opening, .... I've had instances where people stop hearing the
> entry warning beep and think that the sounder has gone bad and simply
> keep arming and disarming the system, not realizing that the door switch
> is bad.
>
> Magnet falling out of door?   I can only say that if an installer
> doesn't silicone the switch and magnet in the door they deserve the
> service call.
>
> One question I have about the  use of roller ball switches, ............
> since their "play" seems to be a primary factor in your use of them, why
> wouldn't  you use a push button on the jamb side of the door that has a
> greater throw and would MUCH less succumb to changes in the door-to-jamb
> gap? I'm guessing that a roller ball switch has a throw of about 3/16
> ths of an inch, whereas a pushbutton switch would have at least a
> 5/16ths inch throw.
>
> I very rarely use a roller ball switch for anything unless I have no
> other choice because it has such a small throw tolerance as compared to
> a pushbutton switch.
>
> Both the push button and roller ball switches now contain micro switches
> but in years past, in the land before micro switches, there was only the
> Ademco 116 push button switch. There was only that choice for door
> contacts if  you didn't use a serface mount switch. Although after about
> 10 years or so in use, they could give you a real pain in the ass, they
> had about a 1/2 throw on them and once installed hardly ever needed an
> adjustment. I still have some jobs where they don't get used much and
> are still in service after 30 or so years. And because of the more
> powerfull spring, they hardly ever got hung up when used on doors.
> During the years while the microswitch type pushbuttons were being
> introduced I kept trying to get the manufacturers to lengthen the throw
> on them and increase the spring pressure but they never did. That's when
> I started using the recessed mags more and more.
>
> On occasion I'll have to utilize what was already installed on a job and
> when I do, if it's a hinge jamb switch, I'll use a pushbutton over a
> roller ball just to gain the greater throw.

I have a GE-Sentrol magnetic contact switch on my overhead door.  It's
designed for floor mounting, though it's can also be located at the top
of the door.

http://www.nextag.com/GE-2202AU-L-Overhead-528938221/specs-html