Editing Security alarm (section)

===Hermetically sealed reed switches===
[[File:Reed Magnetic Switch.png|thumb|150px|left|Reed Switch]]The hermetically sealed [[reed switch]] is a common type of two-piece sensor. This switch operates with an electrically conductive switch that is either normally open or normally closed when under the influence of a magnetic field in respect to proximity to the second piece, which contains a [[magnet]]. When the magnet moves away from the reed switch, the reed switch either closes or opens, based on the normally closed or open design. This action, coupled with an electric current, allows an alarm control panel to detect a fault on that zone or circuit. These sensors are common, are found wired directly to an alarm control panel, or are typically found in wireless door or window contacts as sub-components.