Four state zone wiring

[mikefamig]

I have been searching for a half hour and can't find the answer to a question that I;m sure you guys can help me with. I am looking at page 9 of the Elk M1 installation manual and have a question about four state zone wiring.
 
Four-state wiring shows two contacts, the alarm contact and the tamper contact. I assume that the alarm contact is the same as in a 3-state zone which is closed when armed. I do not understand the operation of the tamper contact. The diagram shows a normally closed switch which is the same as the alarm contact. Using a window as an example, is the same type of device as the alarm contact? Where is it installed and what is it's armed and disarmed state?
 
Thanks in advance, Mike.

 

[pete_c]

I do not understand the operation of the tamper contact.

 
I always have assumed that the tamper contact was for the device itself relating to the little switch present that opens and closes when you remove the cover or open up the device. (well like a PIR)
 
A window I assume to be just two states either open or closed; well unless its some intelligent device I guess.  Ideally though its not seen nor powered; something like an RF device would probably have more ....(well virtually though).
 
In the OPII panel its just an option for a zone.  (see attached).
 
You can also utilize it in a "wired" sort of "if then if then if then then do mode" using the logic of the closed or open state of series of switches (loop like).  Personally I do not know if this is a correct logic; but it does work.

 

[RAL]

I can't think of why you would have a tamper switch in a zone with a window contact.  More likely, a non-powered zone with both a contact and a tamper switch would be something like a keyswitch.
 
But that doesn't mean you can't use the 4-state wiring with a window contact and no tamper switch.  It would still give you better information on the zone state than the 3-state wiring would.

 

[mikefamig]

I can't think of why you would have a tamper switch in a zone with a window contact.  More likely, a non-powered zone with both a contact and a tamper switch would be something like a keyswitch.
 
But that doesn't mean you can't use the 4-state wiring with a window contact and no tamper switch.  It would still give you better information on the zone state than the 3-state wiring would.

I can't think of why I would want a tamper switch in a window either which leads to another question - what is a tamper switch and  do I want a tamper switch in a window.
 
I am not seeing how I would use the extra info either. Opening the tamper switch in the diagram is the same thing as cutting the zone wire depending on where the switch is in the circuit. If it is right at the alarm contact like in the diagram then I don't see what purpose it serves.
 
Mike.

 

[BraveSirRobbin]

The tamper switch lets you know someone is trying to thwart the sensor by prying it open.  The internal switch will trip usually if the case itself is opened.
 
This is sometimes useful for an 'exposed' exterior sensor (say motion sensor for instance).
 
One could always just wire the tamper in series with the contacts IMO and you would just get the same 'alarm' notification.  Afterall if someone is trying to take your sensor apart you most likely want an alarm notification on that zone anyways IMO.
 
Others of course may have a different opinion.

 

[pete_c]

I have seen though historically (well personal experience) an exposed windows sensor causing an issue to a person "cleaning the window" not knowing what it was and trying to remove it as it is in the way of same said person.  (causing really more grief say if there are multiple switches in a one room loop or say a multiple windows in a single loop of a series of switches in yesteryears methodologies)

 

[RAL]

I am not seeing how I would use the extra info either. Opening the tamper switch in the diagram is the same thing as cutting the zone wire depending on where the switch is in the circuit. If it is right at the alarm contact like in the diagram then I don't see what purpose it serves.

 
The extra resistor would let you easily determine whether you have an open (non-tamper) contact vs a cut wire (or tamper condition).  With the 3-state wiring, you would just get a "not ready" condition for both cases, since they look the same at the panel.  With the 4-state wiring, you would get either a "not ready" for the open contact, or a "sec. alert" for the cut wire.
 
Admittedly, this is not a huge value-add for the typical home owner since a cut wire is a low probability event.  Probably makes better sense in a commercial environment.

 

[mikefamig]

From what I hear so far I think three state wiring is it for me.

 

[Del91574]

4 state would be overkill for most applications.