One zone, two areas

dbuckley

New Member
Hi, first post question, about M1G, which is on a (very) short list of replacement systems for an alarm system that has become end-of-life.  I'm hoping going with M1G will fulfill many of our desires, and resolve a few bodgy workarounds.  So...
 
We have a pair of doors that join two areas, areas that may be used (and thus have their area set) independently.  The doors have contacts wired to a zone. But, in common with every other alarm system out there, the M1G allows a zone to be part of only one area.  This is a aggravating annoyance requiring some sort of work-around.
 
Is there any elegant way to have a zone turn up in more than one area?  Present ugly solution is a relay, with contacts wired to two zones to two areas, but that makes the circuit unsupervised.  I've though of using a rule, but I cant see that one can have phantom inputs like one can have phantom outputs.  I muse if one could electrically connect two zone inputs together, almost certainly needing to alter the value value of the EOL resistor to get the non-violated voltage correct, but some panels treat zones connected together as a fault and raise trouble.  Third idea was wiring one zone normally, and having a second zone hard-wired into in violated mode, and having a rule to bypass or un-bypass the second zone.  Or I could have a rule echoing the zone state to an output, and then using a relay with its contacts being the second zone input.  Or the same thing but no relay, just the right value resistors to correctly shift the switched positive output voltage to the correct voltage for the zone input.
 
Anyone have any suggestions or comments?  I don't want to have a second contact on the door as that involves wall-work that would be messy, I'd rather have an in-panel solution.
 
 
 
 
 
 
dbuckley said:
Hi, first post question, about M1G, which is on a (very) short list of replacement systems for an alarm system that has become end-of-life.  I'm hoping going with M1G will fulfill many of our desires, and resolve a few bodgy workarounds.  So...
 
We have a pair of doors that join two areas, areas that may be used (and thus have their area set) independently.  The doors have contacts wired to a zone. But, in common with every other alarm system out there, the M1G allows a zone to be part of only one area.  This is a aggravating annoyance requiring some sort of work-around.
 
Is there any elegant way to have a zone turn up in more than one area?  Present ugly solution is a relay, with contacts wired to two zones to two areas, but that makes the circuit unsupervised.  I've though of using a rule, but I cant see that one can have phantom inputs like one can have phantom outputs.  I muse if one could electrically connect two zone inputs together, almost certainly needing to alter the value value of the EOL resistor to get the non-violated voltage correct, but some panels treat zones connected together as a fault and raise trouble.  Third idea was wiring one zone normally, and having a second zone hard-wired into in violated mode, and having a rule to bypass or un-bypass the second zone.  Or I could have a rule echoing the zone state to an output, and then using a relay with its contacts being the second zone input.  Or the same thing but no relay, just the right value resistors to correctly shift the switched positive output voltage to the correct voltage for the zone input.
 
Anyone have any suggestions or comments?  I don't want to have a second contact on the door as that involves wall-work that would be messy, I'd rather have an in-panel solution.
 
Hi and welcome to Cocoontech!
 
I think you've thought through all the possible solutions pretty well.  I would not try to tie two zone inputs together to the one contact.  As you say, it would probably cause some problems - at least some fiddling with the EOL resistor.  Might not damage the input circuit, but I wouldn't want to risk it.
 
I think your third idea of using a relay to mirror the door contact is probably the best solution.  You could use Output 3, which is a form C relay to do this, without requiring additional parts.  Or, it you need Output 3 for some other purpose, then connect an external relay up to a voltage output to do the mirroring.
 
If you don't need the door to trigger an alarm condition, but just turn on lights or whatever, then you could do it with just a phantom output.
 
How about adding a second sensor to the doors? Then you have one sensor for each zone and you could name them the same or similarly.
 
Mike.
 
If the hole was sized large enough, just swap out the contact for a DPDT contact and you're done.
 
The other option is to make the door a common logic area that only arms when the other 2 areas area armed. I don't know the physical layout and usage patterns, but this is very commonly done in commercial buildings/offices/malls that have a lobby that is secured and businesses/offices that area attached or must be accessed via the common lobby.
 
mikefamig said:
Nice, I didn't know any such thing existed.
Got a bunch of them next to me here. Usually 3/4 or 1" trade sized. Usually DPDT and form C in the contact instead of NC.
 
In the OP's case, I'm thinking 3 areas with one being common to the two main areas and armed accordingly is the best solution.
 
Hi Folks, thanks for the input.

What I've now come to realize is that I don't fully understand how this would all work in practice yet; I've put the technology cart before the user convenience horse.  I don't have a clear perspective on how this world work for the users. 
 
The first issue is that this is actually an access control problem, and when I figure out how that will work then the alarm can be slaved to access control.  The access control needs to have a "groups" mentality, as the overall situation is that there are more than just the two areas I described originally, there are several other areas that people need to be able to get in by permission.  So that is what I need to work out first.  I'll leave the existing (imperfect, but not terribly so) alarm as-is until I've implemented access control, and when everyone is competent with that, then replace the alarm system.
 
DELInstallations said:
The other option is to make the door a common logic area that only arms when the other 2 areas area armed. I don't know the physical layout and usage patterns, but this is very commonly done in commercial buildings/offices/malls that have a lobby that is secured and businesses/offices that area attached or must be accessed via the common lobby.
 
I hadn't thought of making the doors an area all of their own, that's a neat idea. But... although many panels offer the option of a common vestibule to two or more areas, they all work the wrong way up. The vestibule logic is that the common area is disarmed when any of the of the office areas are disarmed; I want the "common" area to only disarm when both office areas are disarmed.
 
Again, thanks, I'm sure I'll be back!
 
 
What you would do is modify the areas so that both are common to the 3rd area.
 
You still haven't mentioned what the application is why and how an area would only have a door or two that are required to be disarmed only when X and Y are true.
 
More information might help here.
 
They say a picture is worth a thousand words, but I cant upload images, so some ASCII art of the genesis of the problem:

+-------------------+--------------------+
| | |
| | |
| Area A | Area B |
| - |
| Z |
| - |
| | |
+-------|X|---------+--------|Y|---------+


Areas in use Door X Door Y Door Z
============ ====== ====== ======
Just Area A unarmed armed armed
Just Area B armed unarmed armed
Both Area A and B unarmed unarmed unarmed
None armed armed armed(*)

Area Z is the "automatic" area that is never armed or disarmed by a user at a keypad, it is automatically armed or disarmed as required depending on the states of Area A and Area B.
 
*: although this door is shown as armed in the "no area in use" status, it doesn't actually matter if it is armed or not, because its an internal door and no-one can get in there anyway, without violating one of the areas.
 
You could use a rule and a relay to shunt the door based on armed conditions of the individual areas or there are other ways to go old school on the panel, as you already have. If you wire it correctly, the zone can be supervised. I'm knee deep in some other stuff, but it could also be done via common lobby/areas, however you would need to consider how your areas are armed and disarmed, which would typically involve a UI for each area.
 
Basically, you would have 4 areas, 1 common to #3 and your two individual areas. the arm status of the main area would affect the common, which would in turn affect the controllable point. Basically performing logic within the panel based on armed conditions.
 
Other way would be to run phantom outputs and then track the armed status of the two main areas via then and then use that to arm/disarm the area containing the common door.
 
All doable.
 
If I understand the problem correctly then think that this can be done with four rules. First make the connecting door an area of it's own so that one room is area1 and the other room is area2 and the connecting door is a single zone area3.
 
Whenever area1 becomes armed
then
arm area3
 
Whenever area2 becomes armed
then
arm area3
 
Whenever area1 becomes disarmed and area2 arm state is disarmed
then
disarm area3
 
Whenever area2 becomes disarmed and area1 arm state is disarmed
then
disarm area3
 
Mike.
 
Mike,
 
(bear with me, been a long week)
 
You'd toss the single door into an area which would then in turn be common to the 3rd area, affected by first 2 areas. The disarm would not require a rule as once the 2 interlinked areas change state, that would affect the common area, which would in turn disarm (or arm) the single door area, via the common logic. This would effectively invert what is the common area through a pair of rules vs multiple.
 
Area 1 disarms affects common
Area 2 disarms affects common
Area 3 is common, affects area 4 (inverted via 2 rules)
Area 4 is common DC.
 
Less rules used and not affected on a larger level, 2 rules based off common arm state and you're done.
 
DELInstallations said:
Mike,
 
(bear with me, been a long week)
 
You'd toss the single door into an area which would then in turn be common to the 3rd area, affected by first 2 areas. The disarm would not require a rule as once the 2 interlinked areas change state, that would affect the common area, which would in turn disarm (or arm) the single door area, via the common logic. This would effectively invert what is the common area through a pair of rules vs multiple.
 
Area 1 disarms affects common
Area 2 disarms affects common
Area 3 is common, affects area 4 (inverted via 2 rules)
Area 4 is common DC.
 
Less rules used and not affected on a larger level, 2 rules based off common arm state and you're done.
 
This is very interesting.
 
So
when areas 1 and 2 are dis-armed then the  common area3 is dis-armed so the area4 is inverted to armed.
when areas 1 OR two is armed then the common area3 is dis-armed and the inverted area4 becomes armed
 
good so far but
 
when areas 1 and two is armed then the common area3 is armed and the inverted area4 becomes dis-armed....is this ok?
 
Or am I following you right? I think it's a neat concept to invert the common area logic, very inventive.
 
Mike.
 
Too many rum cocktails to think straight, but I'd have to look at it with fresh eyes, but really shouldn't make a difference if the door is only a common partition between the two areas, assuming they're both armed. Nobody should be able to get through the door and violate the main areas.
 
Looks like the door is more of a partition and preventing the parties from accessing the other space unless both spaces are occupied.
 
Still think more details would need to be known, but barring really worrying about the supervision, it's easier using relay logic and shunting the contact, which is what I believe was done. How that's presently affected would probably be very similar to how common lobby would work.
 
The other option, assuming enough conductors, would have a DPDT contact, assigned to each area and work appropriately as a protective point in each area, no additional programmin.
 
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