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Stitch two glass breaks together?

I have a kitchen with big casement Anderson's in two areas -- one on the West wall and one on the North wall. I understand you need to "point" a glass break acoustic sensor at the window, correct? That means I need two, one pointing North and one pointing West. I also have an English keypad with a 4-zone expander built into it next to the kitchen door. Can I get two 2-wire acoustic sensors and daisy chain them together like magnetic sensors, or does it not work like that? And, can they be hooked into the zone expander in the napco keypad, or do they need to be plugged into the panel? On a related question -- how important is the acoustic sensor to be poiting exactly at the window in question? I have another room with a row of windows long enough to take up the whole 25' wall. If I point a sensor directly at the wall, it will only really "point" to two of them. If, however, I mount it on the same wall as the motion sensor, it will "look down" the room, flanking all the windows. Will it still work properly? Is it just a microphone and pointing it at a window is not as impotant as it seems? thanks

Reply to
Total nerd
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Depends on the acoustic glassbreak, some have to face the window, some pickup in 360 degree pattern.

Yes you can series the relays (NOT the power) of glassbreaks, you won't know which one tripped though unless they have a selectable latching jumper - this is only important if you have falsing problems and need to know which of the two is falsing.

I'm not that familiar with Napco panels but if the keypad power is the same as the aux power terminals in the panel, you could run your glassbreaks off of the keypad in the kitchen and the zone(s) off the keypad expansion loops as well. (this should be verified with one of the Napco guys here first).

Two wire glassbreaks...usually piezo's or have small batteries in them and have to attach to the glass...ie...they don't have the coverage that a acoustic would.

Reply to
Crash Gordon

There are audio glass break detectors that you can mount on the ceiling that will cover an area of 60 feet in diameter or up to 30 feet if mounted on a wall. See IEI's model 510.

As far as using the zones on the Napco keypad ..... no problem. However, if you're going to use the power at the keypads for the Glass break detector, it's not advised. The power for the keypads is not the same as the Aux power output and if a short occurs, you'll disable the keypads. I guess, if you wanted to add an inline fuse holder off the keypad voltage, it'd work, but you'd have to use a VERY small fuse, like

1/8amp, if there is such a thing. Also, keep in mind that each keypad uses about a hundred mils when lit up, so you cant have a lot of keypads. Each glass break detector uses about 30 mils. Putting two of any kind of passive or active type sensor on one zone is not recommended. Mainly because of the problems it causes when trying to trouble shoot. If this is your own system, you may not care if it takes you longer to find a problem. When you do this for a living, as we do, finding the source of the problem, as quickly as possible is important.

If at all possible, run a new wire from the main panel for the glass break detectors.

Reply to
Jim

Thanks for the info. I have a few 2-wire Firewolf smokes strung together and once one of them falsed on me. You're right, I didn't know which one it was at the panel, it simply said Fire, but infact these have a little red LED on the one that trips, so I saw it. I think the problem is that I'm running out of zones at the panel. In fact, I think I'm out now. So, that leaves me with the keypads. I want to use them as much as possible... the nearby doors, windows, etc. It would be great if they could also be used for the nearby glassbreaks and motions too, but apparently you're saying that can't... someone else responded to another post saying that the keypad's bus power is the same as the aux power. Maybe I can run only power from the panel and hookup the 2-wire zone contacts to the keypad only, just like an un-powered door magnet. The keypad won't know the difference, right?

Reply to
Total nerd

Running power from the keypad sounds good. Another suggestion that (I think) Crash made in another thread is to purchase a small 12volt power supply and standby battery and mount it in a closet near the keypad. It may prove to be the "easier" solution compared to running wires from the main panel.

Reply to
Jim

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