contacts in the sensors are normally closed? What does that mean?
means attaching the sensor is like connecting the two wires together on the door/window module(disconecting them or opening them sets off the alarm)
I've just finished reading the directions! The window/door sensor actually have another wire inside it or do i have to get my own or cut the original to size from the window/door module?
The window/door module has two wire comming from it to the magnetic switch.
The wired glass break sensor has two wires comming from it also.
If you want Just the glass break sensor installed connectthe two wires from the module to the two wires from the sensor!
If you want a magnetic switch in combo attach one wire from the glass break to the magnetic switch and one to the module. Connect the other wire from the module to the free terminal on the magnetic switch!
In the link I posted the magnetic switches have no wires of there own! hence the extra wire!