Multiple COSMOD2W integration


Active Member
The COSMOD2W comes up repeatedly in this forum and frequently in regard to using more than one of them for multiple zones. Forum members graciously explain the issues involved and indicate vague/unstated hardware and/or programming workarounds. All of us would benefit from more concrete details about these solutions.
Back in 2018 I built a new home and installed 2 COSMOD2W, each with a few detectors. For various reasons I really wanted to know which of two floors was the origin of alarms. With the input from this forum and some experimenting I came up with a complete hardware configuration (I hope) that addresses all the issues (yes, its ugly). I have this setup installed and it is working completely as far as my testing has shown. I've attached a PDF with a wiring diagram; page 1 is for my dual-COSMOD2W configuration (scalable to any number) and page 2 is for a single COSMOD2W (untested and mainly provided as a simple example - start there to understand).
I would like to see a detailed discussion here of anything that is wrong with this setup. I have moderately tested at least the smoke portion and haven't seen a problem yet. I have tested the CO, but less. Further, I would like to see details of how this would need to be changed for other popular panels and most importantly, details about how to program said panels. I would note that vague programming references may work for people already familiar with specific panels but are nearly useless for those of us who aren't. Given my unfortunate choice of panel I will likely be changing mine in the not too distant future.
There are multiple Altronix RBSN relays and one Altronix 6062 timer. The setup is as required by my panel (Interlogix UltraSync unfortunately). On my panel at least, an alarm reset drops the negative power and the smoke trigger goes negative.
The CO & Maint Override relay bypasses the COSMOD2W CO and maintenance during reset (the Reset Override relay handles when the power is off) and for up to 1 minute after power first comes back (the Power-On Delay Override relay) allowing the COSMOD2W and detectors to stabilize. The trigger relays simply invert the polarity of the signal.
This setup prevents secondary alarms during the reset cycle and provides for the all-zone-sounding.
Obviously it would be preferable if none of this was necessary. I have yet to see information about any other panel that clearly spells out how to avoid this special hardware. Like most people I imagine, I'm not going to buy a variety of panels and experiment with them to figure out these details. As we all know the documentation usually stinks. Vague statements of "it can be done" or general how-to isn't enough in my book to buy a product. I would love to see someone say exactly which panel wired in exactly what way and programmed exactly as described will completely solve the issues and make a robust viable solution.
It would be wonderful if the conclusion of this thread was the definitive solution(s) that could be referred to going forward!
Clean exterior. Interior is a bit of a mess as one would expect - sorry, don't have a pic handy.


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Can you explain further why you need the CO and Maint overrides? From your description, it sounds like when you power up the alarm panel, the COSMODs are presenting a false indication on these signals and you solve that with the the delay and bypassing them.
When happens when you have a smoke or CO alarm condition on one of the COSMODs, and then try and reset the smokes?  Doesn't the reset cause problems with the non-alarm COSMOD?  I would expect the loss of power to cause a false alarm condition on the non-alarming COSMODs input to the alarm panel due to the loss of power.  Or do you do a full system reset and reset the Ultrasync as well?
I don't see anything wrong with what you are doing.  Having multiple COSMODs creates extra complexity, but what you have is a bit different from what I would have expected.  But maybe that is due to differences between the way your Utlrasync system works vs my Elk M1.
An alarm reset was causing several subsequent alarms requiring multiple clears. I didn't fully bench analyze what was going on at the time since I was deep in build chaos. At least partially it was a problem with the non-alarming COSMOD. I may have gone overboard on what was required. It may be possible to reduce the number of situations that need hardware workarounds by programming but alas I haven't figured out how to do that with the Ultrasync. Given the death of the brand I don't really have any interest in further Ultrasync effort.
I am considering what to replace the Ultrasync with. I keep reading that the Elk will address all these issues yet with my zero-knowledge of Elk I'm still not clear exactly how. The other option I'm thinking of is an older DSC 1864 but it doesn't look easy either. It's a bit surprising that there seems to be no how-to guide on the vast interwebs.
@jeditekunum Sorry to resurrect an old thread. I really appreciate your diagrams. There's very little information about configuring multiple COSMODs. I'm attempting to set this up with DSC Neo.
@jeditekunum Sorry to resurrect an old thread. I really appreciate your diagrams. There's very little information about configuring multiple COSMODs. I'm attempting to set this up with DSC Neo.

@Dblessing Wish I had useful information to help. Here we are 3 years since my last post on this and I still haven't done anything to my setup. I've almost come to the conclusion that alarm panel programming is a "dark art". Most documentation I've come across looks like it came from the style of 50 years ago - sparse and cryptic.

It's easy for me to say "it's just multiple fire and CO zones" but I can't even remember how I did it with my panel.

The last time I thought about this, a year or so ago, my plan was to try a Bosch B series panel. If I recall correctly, the design seems comparatively modern and the documentation was surprisingly good.