2-wire reversing relays and the Elk

Mike

Senior Member
I recently ordered some System Sensor i3 2WTA-B smoke alarms for use with an Elk M1 Gold.

In order to get them all to sound in an alarm condition, it notes the panel needs to support polarity reversing or use a reversing relay.

From reviewing the documentation, I need to install the RRS-MOD reversing relay to get this to work for the Elk, right? Just want to make sure I didn't miss something.
 
Mike, I believe you are right! Those are the units I put in and for some reason I thought the panel handled it. I just tested it and only the local/tested unit and the panel went into alrm. The other detector did nothing. Guess I'll have to add 1 to my shopping list too!
 
Man this smoke/fire stuff is confusing for DIYers. :( Makes me wonder how many installs are even close to correct (code wise). I would love to see a tutorial on what is the "best" way to really use the M1. I have never even seen reversing relays mentioned in the Elk docs. How do we know if the M1 supports them or how to wire them?
 
WayneW said:
Man this smoke/fire stuff is confusing for DIYers. :( Makes me wonder how many installs are even close to correct (code wise). I would love to see a tutorial on what is the "best" way to really use the M1. I have never even seen reversing relays mentioned in the Elk docs. How do we know if the M1 supports them or how to wire them?
Agreed, this is more complicated than I expected.

From what I could gather from the documentation on the System Sensor site, it is:

1. The panel supports reversing the polarity and no changes are required (other than telling the panel to do this I presume).
2. If the panel does not support that, this relay does it for you. (although one area below says it must be used, but later on it says if the panel does not it may be used, but that may be referring to a scenario where only one detector is on the zone)

In the second case, it is for scenario's where the panel does not support this function if I understand it correctly.

From : http://www.systemsensor.com/pdf/I56-2170.pdf

Models 2WTA-B, 4WTA-B, 4WTAR-B, and 4WITAR-B contain a piezoelectric
horn which generates the ANSI S3.41 temporal pattern in an
alarm condition. All detectors on a zone will sound when the power
supply to them is reversed. The RRS-MOD can be used for the power
supply reversal function. The RRS-MOD also enables all the detectors’
sounders on a zone to be synchronized and allows the zone to
be silenced from the panel by entering the alarm silence key at the
keypad.

NOTE: In order for all i3 sounder detectors on a loop to sound
when the panel alarms, the supply voltage polarity must
be reversed. A reversing relay, System Sensor model number
RRS-MOD, must be used. The RRS-MOD is designed to
allow all i3 Series detectors in the same loop to sound when
one of the detectors goes into alarm. In addition, the RRSMOD
will synchronize all of the i3 Series sounder smoke
detectors on the loop. Some panels may require the use of
programmable outputs. Refer to System Sensor literature
for further information on the RRS-MOD.

NOTE: Only one 2WTA-B detector shall be installed on a zone,
unless the panel switches the zone to a reverse polarity,
non-current limited power supply. For panels that do not
provide this feature, a reversing relay, System Sensor
model RRS-MOD, may be used. When utilized with
the 2WTA-B, it allows for more than one detector to be
utilized on a loop. Some panels may require the use of
programmable outputs. Refer to System Sensor literature
for further information on the RRS-MOD. The 2WTA-B
detector shall not be mixed with other 2-wire detectors on the same zone
 
Not to complicate things any further but I notice the i3 detectors use an integral piezoelectric horn. Does anybody know the center frequency for this device? Many piezoelectric devices operate at a fairly high pitch that is difficult for elderly people hear and would not be suitable in applications where the household includes older members.
 
Mike,

Not sure. We carry all of the Elk relays but I'm not sure if they do that.

Also, I guess we need to find out from David if that's even needed.
 
Excellent point. It's not an elk product (the one I noted RRS-MOD) its a System Sensor part. I would guess it is the kind of part like the end of line relays (are essentially standard) but this topic has already become a little more complicated than I expected.
 
Maybe more complicated than you expected, but it has been very educational to me. Now I understand a little better why some alarm hardware companies don't like selling to end-users. But I am glad that Elk does even though I think that means they need to do a little more education and/or documentation so us HA/DIYers do it "right". I am glad I am not the first or only one bumbling down this road. I really want my smoke/heat sensors to be "right" (to protect my home and loved ones), but it sure would be easier to just keep using those $10 stick up smokes from HD/Lowes. Cost is only a small part of the issue. I want to do it "right" and I don't want to have to place 5 orders from 5 different companies at 5 different times to get it all working eventually.
 
upstatemike said:
Not to complicate things any further but I notice the i3 detectors use an integral piezoelectric horn. Does anybody know the center frequency for this device? Many piezoelectric devices operate at a fairly high pitch that is difficult for elderly people hear and would not be suitable in applications where the household includes older members.
The only thing I could find in the specs was 'temp-3 tone'. I'm not sure if that means anything. It appears to be an ANSI/NFPA standard but I haven't tracked down a non-contradictory answer yet (there were a few different frequencies I found so I'm missing part of the answer here clearly).
 
I just checked the spec sheets that come with them. The only thing I could find is that it's 85dB.

It also has a whole section about warnings. Things like you might not hear it if your deaf, stereo too load, or on drugs, etc.... :(
 
'temp-3 tone'

I believe that refers to the sequence of tones, not the frequency. I'm on duty at the moment, so I don't have my copy of NFPA72 handy, so I could be wrong. NFPA recently (within the past ten years) required fire alarms to use a "universal evacuate" signal, three beeps followed by silence. Beep, beep, beep,.......beep, beep, beep, etc.

I don't recall working with the i3 series, so I don't know firsthand what the frequency is, but some of the other System Sensor products are on the high side. Beyond the hearing of older folks? I don't know. I do know that when they all go off, I REALLY want to stick my fingers in my ears and run. If the panel/sounder allow voice messages, I also play an evacuation announcement loud enough to wake the dead.
 
I also play an evacuation announcement loud enough to wake the dead.
Good point. I suppose if the pitch was too high you could always add a supplementary sounder or voice announcement so maybe this isn't really an issue.

Probably a more important consideration in planning is the impact of integral sounders on power and wire gauge calculations. It looks like the sounder brings the alarm current per detector up from 30mA to 130mA. Depending on how many detectors you have on each zone and how long your zone runs are, you may have to up your wire size to avoid too much voltage drop in alarm.

You also need to be careful where you are drawing the sounder current from (zone or aux power). And keep track of the total current drawn in a worst-case situation (all fire zones in alarm, all integral sounders operating).
 
:( Smoke Detectors and reversing relays. :)

The official answer is to buy a UL approved reversing relay module made by the manufacturer of the smoke detector and seek advice from a licensed installer concerning Fire Alarm installations. This is life safety equipment and must be installed correctly. Your family's life is at stake.

*********************************************************************





To connect a reversing relay module to the M1:
Attach the positive power input to the reversing relay module to the smoke power output terminal, just below zone 16 on the M1. Negative to one of the negative terminals.

Program a rule that turns on Output 3 (or another relay output on an expansion module) when the Alarm activates. Another Rule that turns off Output 3 when the Alarm de-activates. Use the common terminal on Output 3 relay to the smoke power terminal and the normally open relay terminal to the reversing relay trigger input terminal.

When the Alarm activates the reversing relay module will reverse the power supply voltage to the smoke detectors and cause all of them to go into alarm when the voltage polarity is reversed.
 
Wow this post is old, but I still have a few questions.

1. I want to install 4 wire smokes as individual zones on my M1.
2. I assume I need an external power supply to run the smokes? (5 total upstairs, 5-8 total downstairs and basement).
3. If I want them all to sound at the same time, do I need a reversing relay on each smoke since they are going to individual zones, or can the M1 handle this? (Spanky made some reference to this above, but I think its for a 2-wire setup).
4. I am planning on leaving my original 120v smokes wired, but would still like to have those also sound, so whats needed there?
5. If the 120v's goes off, i would like the other on the M1 to sound, so whats needed there?

Once I get this all together, I think Ill write something up on how its done, Im just still a little confused with all the options. Any help would be appreciated.

Thanks
 
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