Zone and tamper doubling on NX-8

[sowhat]

Hello!

I am really stuck for few days on trying to add ninth detector to my system in the garage.

I connected new detector to zone 6 and replaced old resistor with new one 3.74K for doubling and also added one more resistor 6.98K in the new detector. Turned on zone doubling and selected zone 6 and 14 type to 19.

Now I have following wiring on both detectors:
com - tamper IN - tamper OUT - resistor - Relay IN - Relay OUT - Zone 6

And the problem - every time I cross room where detector is located, it reports tamper problem.

I think there is something wrong with wiring, but one expert told me that I should connect it like that.

Please help me!

 

[sowhat]

why nobody helps me? B)

 

[BraveSirRobbin]

Well, you are using a system a lot of people are not familiar with, especially in a "zone doubling" mode.

Let me try. Do you know what the resistance levels should be for the different scenarios?

Everything "normal"

Tamper Trouble

Motion

Tamper Trouble and Motion

That would be a start. Then to check your wiring I would take the two leads to this sensor off the alarm panel. Then get a meter that can measure resistance and try to take resistance readings between those two leads while you simulate the above conditions. This will at least tell you if the problem is in the software setup or in the hardware.

 

[sowhat]

thanks for replay!

I don't know resistance levels B) they aren't mentioned in users manual, but I will measure what I can.

So here it goes:

No movement: 2.73K
Movement on zone 6: 3.66K
Movement on zone 14: 6.70K
Tamper open on zone 6: 6.72K
Tamper open on zone 14: 3.67K


here is a little illustration of my wiring:

 

[BraveSirRobbin]

I'm trying to figure out exactly how you have those two motion sensors "Zone 6" and "Zone 14" wired. Are they BOTH wired into the NX-8's channel six input?

 

[sowhat]

yes, they both are on channel 6. Zone doubling enables adding 16 detectors to 8 chanels

 

[BraveSirRobbin]

I am not a security expert and not familiar with zone doubling, but it's my understanding that if you use a tamper PLUS the actual motion sensor contacts with a resistor array such as yours, that constitutes TWO zones (the "tamper" counts as one zone).

Can you remove one motion sensor/tamper combination and test again?

 

[sowhat]

here you can take a look at NX-8 install manual.
Zone doubling is very cheap way for extending your panel

As I understand in my wiring, there should not be any difference between cutting detectors wire and opening detector, because tamper contact resistance is so small (0.01K).

Default wiring diagram for zone doubling:

So the question actually is where to connect tamper contacts and what to do with programming?

 

[sowhat]

Latest news:

I changed zone type to 6 = INSTANT - This zone creates an instant alarm whenever it is tripped and the Armed LED is on.


And everything works fine except one thing - system reports "Service required, Type *2 for help" And *2 reports that zone 14 is tampered.

How to take away this message?

Everything else is okay - alarm works and reports correct zones.

 

[WayneW]

I don't know resistance levels they aren't mentioned in users manual, but I will measure what I can.

So here it goes:

No movement: 2.73K
Movement on zone 6: 3.66K
Movement on zone 14: 6.70K
Tamper open on zone 6: 6.72K
Tamper open on zone 14: 3.67K

Without documentation to the contrary, I believe that zone 6 movement resistance is too close to zone 14 tamper resistance for a modest alarm panel to discriminate. 3.66k is too close to 3.67k. same for 6.70k being too close to 6.72k.

In simple terms, I agree with BSR that this panel doesn't support zone doubling and tampers at the same time. At a minimum, you would need another different resistance value or two.

 

[sowhat]

yeah, you are probably right, but I can use tampers anyway, only system won't distinguish movement from tamper opening.
Now I have new problem, please pay attention to may previous post.