External door contact

[RF Lighting]

I'm looking for a door contact detector for a burglar alarm which is suitable for external use.

I want to fit something to the gate at the side of my house to cause a chime on the alarm when it is opened.

Does such a thing exist? I've never seen one before.

 

[bernardgreen]

I have a reed switch sealed in adhesive lined heat shrink on a friend's garden gate post that has been there for several years without problems.. The operating magnet ( recovered from a defunct hard disc drive ) is also enclosed in adhesive heat shrink to protect it from the weather.

The magnet and reed need to be larger than the nornal alarm door contacts to ensure they operate over the wider and variable gap between post and gate.

A suitable 21 mm long reed would be something like this

http://uk.farnell.com/standexmeder/mk23-85-d-2/reed-switch-spst-no-1a-1kv-smd/dp/2453624

 

[sparkymarka]

I've used roller shutter contacts on external gates as they are fully potted or the large aluminium type contacts going into an IP rated junction box , one job has had them on since 2002 with no issues !

 

[scott1980]

As above, roller shutter door contact works well. A 4x4 gewiss box with a normal tampered alarm junction box inside that will do the job. The Aritech DC108 is a compact unit and should last for years.

 

[EightyTwo]

These will work, too - ebay item 380515781406. I'm sure that you can get them elsewhere (and I haven't worked out how to copy and paste in this new forum!)