how to alarm warehouse concertina sliding doors

[nikenyaminyami]

does anyone have any ideas on alarming very large sliding concertina doors? unlike a standard door action, both doors move in this case...

 

[sparkymarka]

Last time I did one ( a long time ago ) I had to create a loop on one door drilled and fixed with p clips
UUUUUUUUUUUU————
Like above

 

[Tigercubrider]

what about fixing magnetic sensors to the frame and the magnets to the door tops?
Could be wired/wireless
.

 

[secureiam]

Do you have an image of the door, open, closed and partially open.

Guessing you only need to see the door is shut and a PIR is covering the internal area behind the door.

 

[sparkymarka]

Think the the issue with this type of door is that there may not be a definite stop the doors can float left or right from the middle position

 

[bsr]

Why can't you use normal wireless door contacts? Frame part on one door, door part on the other.

Or if has to be wired then wire one door as sparkymarka says above.