Normally Closed Switch Circuit. For doors and windows this is usually closed. On off switch spst spst single pole single throw.
The switch is normally closed and held open by a magnetic or held pressed in by the door etc. 2 way switch spdt spdt single pole double throw. The normal status for a switch is the status its electrical contacts are in during a condition of no physical stimulation.
On off switch spst spst single pole single throw.
For the most part normally closed contacts are used on normally closed protection points. On off switch spst spst single pole single throw. For doors and windows this is usually closed. The normal status for a switch is the status its electrical contacts are in during a condition of no physical stimulation.
