1.All doors and windows must be closed well.2.If the unit has detected the air pressure changed suddenly, the LED will turn ON and the white wire will become negative output about 1 second.For example ...
Kuan Chun Technology Corp.
Main Products: AUTO ALARM REMOTE CONTROL GARAGE DOOR OPERATOR CENTRAL DOOR LOCK CONTROLLER CAR ALARM PAGER SIREN PASS-CODE & TIMER CONTROLLER... More