One of the stations continually blink on the control panel, indicating one of the windows are open. They are all closed so I am assuming one of the windows has a faulty sensor. I have check all windows and it appears that all connections are good i.e. all windows still have a magnet that seems to be lining up with the wired sensor when the window is shut. I do not know how to check each window to make sure all is working properly.

jvrattos, May 2009

Without knowing what system it is difficult to give you an accurate answer. Instead I will advise how a window contact works: A window contact is no more than a reed-switch in a vacuum sealed tube and a magnet, the magnet attaches to the window, the reed attaches to the frame. The magnet has to be within circa 5mm and aligned with the reed. To check the contact you need a DMM (Digital MultiMeter) set on a continuity setting (Buzzer). To test the window contact - connect the DMM accross the reed-switch - when the window is closed (magnet next to reed-switch) the DMM will buzz, else it will not. If the DMM fails to buzz you have a dead contact. Contacts are cheap, circa £1.50. It is not uncommon for surface mounted contacts to corrode and fail due to water ingress. Please note that you may also need to check the cable between the contact and alarm system as this may have become damaged.

PR Shields, May 2009