EOL relay and EOLR for 4-wire smoke detectors physical location

[Ira]

I understand that the EOL relay and EOL resistor (EOLR) need to circuit-wise go after the last smoke detector on the loop. But where do most people physically locate them?
 
Using System Sensor 4-wire smokes and EOL relay, is it best to put them in the box above the last smoke, or should wires be run back to the panel and locate them there, or is there a better location? The EOL relay has a max temp rating of 140F, which is about the highest my attic gets to.
 
Thanks,
Ira

 

[pete_c]

Mine (EOL relay and EOLR) is next to the smoke detector in the can (even though its all LV I still utilized a can) which is on the ceiling on the second floor which opens to the attic.  The EOLR is just soldered inline with heat shrink tubing; tiny thing not really noticed.
 
I am not sure if this was the correct way to do this.  The 4 wire smoke adds were a PITA with the HAI OPII panel.

 

[JimS]

Not completely sure if you are talking about the resistor or the relay - both could be EOLR but it seems you are referring to the resistor... Typical temperature rating for a resistor is full power at 70C (158F).  Temp rating increases linearly to 155C at zero power (not sure if that is typical but it is at least close).  The EOLR resistor should be no where near its power rating.  If it was 2k at 12V it would be at 0.072W power or slighty more than 1/16W.  It is probably a 1/4 resistor.  Even derating the part power by 50%, which is good practice for good reliability, it is well within that.  If the ceiling is insulated the box should be below attic temperature too.  The relay may be more of an issue and harder to generalize about the relay.  If you are really worried about it you could run a wire to an inside wall and put the box for it there - probably a lot closer than the panel.
 
Locating them in the panel would require an extra run back to the panel.  I have always seen them located at the last unit. 

 

[gatchel]

If you are wiring in the EOL resistor at the last smoke it can be located wherever you want as long as it is wired properly and accessible for service.
 
You should be wiring in the EOLR in series to the power supervision relay that you should also be installing at the last smoke head per smoke zone...

 

[Ira]

Sorry for the confusion/ambiguity in my original post. I edited it to make it clear. My main concern is the EOL relay (not resistor) from System Sensor, which has a max temp rating of 140F. I will probably locate the EOL resistor next to the EOL relay, wherever that may be.
 
Thanks,
Ira

 

[Del91574]

Resistor gets direct connected to the supervision relay. If needed, you can pigtail.

I have fed extra conductors and installed both in the panel before, but not for the squeamish or inexperienced with wiring.
 
Usually, with a continuous loop, they're in the box at the last detector. If you want to be proactive, a small dot or similar marking on the detector make it nice if you ever forget where it is...just leave a note in the can.
 
If you have a smoke detector installed in a location that gets close to 140, it's not a location where the smoke detector should be installed. If you have a heat detector, run a 4/18 from it to the closest smoke. It's easy enough to feed/return the circuit to the nearest detector and then supervise the loop and power there.

 

[pete_c]

I used this diagram for my installation of the 4 wire smokes to my Leviton HAI OPII panel. 
 
Not sure if its the same for the Elk M1 4-Wire smokes connectivity.
 
Guessing that the M1 doesn't need a polarity reversal module that is in the picture attached.

 

[Ira]

It's an easy run from the last smoke detector back to the M1G enclosure, so I will probably put the EOL relay and resistor in the enclosure.
 
I'm not putting any smoke detectors in a high temp area (i.e., my attic). My concern was about subjecting the EOL relay to high temps if I physically located it "in the open" in the attic above the last detector.
 
pete_c... I am using a reversing relay (in addition to the EOL relay) with the M1G. In my case, it's the System Sensor RRS-MOD (since I'm using System Sensor smoke detectors). It wires up a little different than what your diagram shows.
 
Thanks,
Ira

 

[Del91574]

@ Pete:
 
You don't technically "need" a reversing relay, but in order for a tandem ring to happen and it be coded, you either need to reverse the polarity to the smokes AND provide a temp-3 pulse to the smokes or use a reversing relay. For those that question this as "legal" it is because the host system components (relay boards, etc) are listed for fire alarm service...I used to do it this way when I worked for another company that didn't have reversing relays that functioned properly with the host panel (ESL relay).

DSC's unit is bass-ackwards. DSC panels work off a switched negative, contrary to almost every other panel in the world (barring those that are installed in the EU).
 
@ Ira:

I'd suggest you look into picking up a 4" holesaw and some round old work boxes...or at least one for your last smoke. Use them where your ceiling is wide open and no framing exists and then install the EOL relay in that at the last smoke. Far easier to service than jumping in the attic to troubleshoot.