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26-05-2019 06:31 am
Gikfun MC-38 Wired Door Sensor Magnetic Switch for Arduino EK1656
MC-38 Wired Door Window Sensor Magnetic Switch Home Alarm System Detector
Note: No external power supply, connect to wired or wireless alarm control panel GND and N.C ports directly! Please note that this item not fit to iron door, It will decline magnetic of the sensor
NC means Normally Closed:When the magnet together, the circuit is conductive( light on ); when the magnet separate, the circuit is not conductive ( light off ).
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