Re: "Magnet tamper" for surface mount contact?

["Jackcsg" <nospam@xxxxxxxxxx>]

What you're looking for is called a "BMS" (Balanced Magnetic Switch) I
believe both Ademco, and Sentrol have a model for the application.

"Bill" <bill190nospam@xxxxxxxxx> wrote in message
news:3pg9auFa8cclU1@xxxxxxxxxxxxxxxxx
> Is there a surface mount contact which has some sort of tamper device if
the
> magnet is unscrewed from the door? Manufacturer? Model number?
>
> This would prevent the situation where there is a door which opens out,
> there is a surface mount contact on the door frame, a surface mount magnet
> on the door - then intruder attaches magnet to above contact in some
manner,
> unscrews magnet from door, then opens door outwards.
>
> So unscrewing the magnet from the door or unscrewing the covering over the
> magnet to then unscrew the magnet from the door would trip the contact...
>
> FYI - This is when the intruder gains access through the ceiling or wall,
> but then exits through a door.
>
>