Using 1 wire to connect several window sensors?

[beelzerob]

I had planned on wiring each of my windows individually for contact sensors...but the wiring guide here suggested just wiring them on a room-by-room basis. And I think that's a great idea...I don't really care that the LEFT window in the living room is open, just that any window in there is.

It won't really save me much money, since we're only talking 22/2 wire here....but it could save me a lot of time. But what I don't understand is how I can use 1 wire to wire, say, 2 windows in a room. The windows I'm getting are going to be double hung, so I'm going to have to wire the top and bottom pane. But do I just run the wire across the window and then splice into it a new wire which goes down through the frame? My builder really recommends against having any connection in the wall and inaccessible (obviously high voltage couldn't be, but he believed low voltage I could), and I'm not a big fan of it either. But I just don't see how I would use 1 wire to connect to 2 windows. Do I pull a loop of the wire down through the hole and then splice it there on the frame?

Thanks for the help!

 

[IVB]

With reed sensors, wouldn't you just do something like this?

EDIT: Sorry, the pic makes it look like both sides of the reed are inside the window. Obviously that's wrong, half the reed is outside, the other half is inside the window.

 

[beelzerob]

With reed sensors, wouldn't you just do something like this?

EDIT: Sorry, the pic makes it look like both sides of the reed are inside the window. Obviously that's wrong, half the reed is outside, the other half is inside the window.

Oh...so, instead of using 22/2 wire, basically use 22/1 wire in a big loop? Hadn't thought of that. That could work just as easily I spose.

Not sure about wiring the bottom half, though...someone mentioned it might void the warranty if you drill through the bottom of the window frame. I already asked him about drill through the top and he said no problem.

 

[IVB]

Technically you use 22/2; run the jacket to the room, and then make a big circle with one wire.

Dunno about the warranty thing or how to work around that. I know one of the CQC'ers had to deal with that, and used surface mount somehow, but I'm drawing a blank on who.

 

[BraveSirRobbin]

If you only want to run one 22-2 cable to the window, you would do the "loop" (for the upper and lower part) at that window. If you splice carefully I would not think this would be a problem. One thing I ask that could throw this wiring suggestion for a loop (pun intended) is if you are using EOL resistors. If you are let us know...

 

[beelzerob]

I'm probably NOT using EOL sensors...whatever those are. I'm planning on using the cheapest sensors there are out there. Simple magnetic reed switch kinda thing, maybe?

So, both of your suggestions involve splicing wire in the wall somewhere, though, right? So that kinda takes it back to the original post....how does everyone ELSE use 1 wire to wire a whole room of windows without having to have a wire connection hidden in the wall?

If I DID go with surface mount sensors, IVB, don't I still have to drill through the frame just to bring the wire up to the window from below? Or is there another way?

 

[BraveSirRobbin]

Couldn't you just run one 22-2 to the first window, just use one wire in that bundle to connect to the first window sensor, then run individual wires to all the other sensors, each only "splicing" AT the sensor, then run a 22-2 to the last window using just one wire in that bundle back to the wiring closet. This way you are only running two 22-2 runs for the entire room and not having any "splices" inside the walls.

 

[beelzerob]

Couldn't you just run one 22-2 to the first window, just use one wire in that bundle to connect to the first window sensor, then run individual wires to all the other sensors, each only "splicing" AT the sensor, then run a 22-2 to the last window using just one wire in that bundle back to the wiring closet. This way you are only running two 22-2 runs for the entire room and not having any "splices" inside the walls.

Ok, I see what you're saying, and that's a good idea...just splicing at the sensor. That makes sense, and is a good way to do it.

Along those ideas....do you have any idea how easy 22/2 is to separate into two 22/1 wires? I'm not looking at this like a cost savings, just a convenience of having not to order another type of wire. Is 22/2 just 2 22/1 wires in the same jacket?

 

[BraveSirRobbin]

Along those ideas....do you have any idea how easy 22/2 is to separate into two 22/1 wires?

This really depends on the distance, if it's short, say ten ft or so, it's not that bad, if it's a longer run it could become time consuming as you would have to strip out sections of ten ft or so at a time.

You could run just 22-2 and stip out the extra conductor a ways back from the splice so it doesn't interfere with the other wires going through the sensor's mounting hole.