Purpose of the project:
I need an alarm to protect metal covers (which are rarely opened) they open downward or outward depending on the cabinet)
Our problem is theft of components inside the cabinets and a need to set off an alarm if the cover is opened. We do not want to use reed (magnetic) switches because the cabinets are rarely opened and there is considerable vibration and heat as well as exposure to the elements. Reed switches would require too many more parts for the alarm circuits and increase cost as well as could be damaged by heat, vibration, and water intrusion.
Needs of the alarm:
(1) Description of operation:
The alarm needs to be a normally closed circuit, which would alarm if the wire were cut. A wire loop made of insulated wire, would be intertwined with the vents in the covers.
Should this be cut, the alarm would sound until the battery went dead. I don