New Firelite MS-2

Hello everyone I’m new to this forum. I’m getting my panel in the mail shortly. My question is can I wire a pull and a smoke to each zone with an eol, or do I wire my 4 wire i3 to the 24 dc resettable power,? Or do I wire all my pulls to one zone and the smokes on the other zone? I really really really would appreciate all the help. I’ve been in the hobby for years collecting fire alarm horn/strobes and pull stations and smoke detectors. My wife thought for a late birthday present she’d get me the ms-2. I really don’t want to mess anything up. Anyone’s feedback is highly appreciated and recommended. Thank you.

It really doesn’t matter what devices you put on what zone. The only reason I can think of that you would need to put smoke detectors on a separate zone would be for verification, and even then, you could still have pull stations on a zone with verification, it would just take a long time for the zone to go into alarm. The 4 wire i3 would have 2 wires going to the resettable power and 2 wires going to either zone.



This thread on this forum helped me out a lot, it explains very good tips on how to take care of a panel: <URL url="Basic Rules for Panel Care text=“viewtopic.php?f=60&t=3191”>Basic Rules for Panel Care



Also, I would read the manual, it’s actually not that long of a read and it has some useful information in it: https://www.firelite.com/CatalogDocuments/51512.pdf



Lastly, here’s the manual for the System Sensor i3 series, it has wiring diagrams in it for the 2 and 4 wire versions: <LINK_TEXT text=“https://www.systemsensor.com/en-us/Docu … 6-1800.pdf”>https://www.systemsensor.com/en-us/Documents/i3_Series_Manual_I56-1800.pdf</LINK_TEXT>

I love your channel I’m already subbed! I watched how you explained and wired it up

Thanks so much!

The manual is a good read, and Gentex Guy offered some excellent tips and resources; I’d recommend perusing all of those links for sure!

In a real system “zones” typically designate physical locations (I.E. Zone 1 = first floor smoke detectors/pull stations) but for your application you can wire any initiating device to any zone. If you wire 2-wire smoke detectors together with pull stations on a zone, once any pull station is activated (shorting that zone out), none of the 2-wire smokes will work until the panel is reset. Also be aware that panel verification can only be turned on if the zone is exclusively comprised of 2-wire smoke detectors (among other restrictions) so check the manual for specifics!



Your 4-wire i3 gets its power (the + and - terminals) from the 24VDC resettable power supply terminals on the MS-2, and trips a zone alarm by shorting the zone + and - terminals. From the panel’s perspective it would be the same as if a pull station went into alarm. 2-wire smoke detectors use the zone’s 24V power to operate, so when they go into alarm, they can’t short the zone entirely (like a pull station would), so instead they shunt current through an internal resistor, dropping the zone voltage just enough for the panel to recognize an alarm but not enough to stop the detector from being powered. This is why some conventional panels can differentiate between a smoke detector and pull station, and why compatibility matters when selecting 2-wire detectors.