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Re: Automated front door lock?



> There is, however, a security-related safety decision that you will have to
> make when and if you purchase one.
>
> Namely, in the event of a power failure,  do you want the door to:
>
> 1) fail in the locked position? --   in which case folks may be trapped
> inside and able to get out during eg, a fire.
>
> 2) fail in the unlocked position? --  in which case the bad guys get in for
> free.
>
> Door strikes are available in both styles.

Good point, Marc.  The answer is that if a door strike fails
locked it will not prevent egress.  The strike only retains the
latch while it is engaged.  With or without power the door can be
opened from the inside (assuming there's a conventional lock and
knob or handle in place).

Powered *locks* are another matter.  Conventional electromagnetic
locks simply unlock whenever they lose power.  Sites which rely
on these for primary security should include a battery backed
power supply of sufficient size to keep the door secure until the
power restores or someone is able to implement another locking
means.

Some of the automated locks which I carry are able to function
manually without power.  The lock can be opened from the inside
by pressing the handle or turning the knob.  Some also provide a
backup keyway on the exterior to allow access without power or as
an alternate means for those who are  issued a key.  Following
are a couple of links (my web site) to information on the
subject.

http://www.bassburglaralarms.com/subcategory_506.htm
http://www.bassburglaralarms.com/subcategory_412.htm

Regards,
Robert L Bass

--

Regards,
Robert L Bass
http://www.bassburglaralarms.com


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