Furman PS-8R and Fire Shutdown

[Edrick]

We've got a Furman PS-8R Power Sequencer in an Audio Rack that we installed last year but now the client has been required to add a shutdown based on a fire alarm. The fire alarm company has run a NC Contact to our equipment rack, although I can have them change it to NO. But I got a call randomly today saying "Hey by the way we need this added and we ran a cable to your rack and we need it done tomorrow" it's always fun when people don't tell you about things. So it seems I have two options, either if it's wired as a NC contact as it is now, basically the equipment will be in the "ON" position however the system wont act as a sequencer and basically if an alarm is trigged the system will Open the contact and thus the sequence to shut the system off will be initiated.

I don't think that's the best option as now the user cant use the sequencer if i'm correct?

So if it's wired as a NO contact they can still use the power sequence button on the front as normal and only when the contact is closed will the rack force a shutdown.

Does this sound right? Anyone have a more elegant solutions or do I just need the alarm company to connect it to a NO instead of NC.

 

[techieman33]

I would tell the alarm company to pound sand. In the case of an emergency you may need to be able to communicate with the audience to give direction for evacuation.

 

[Edrick]

It's for a music system in a cafe only and the inspector is requiring it by the fire alarm company, the job was finished a year ago but they only got their final inspection the other day apparently and this was for whatever reason added all of the sudden. Not the alarm company requiring it.

 

[Chris15]

If we're talking about a fire alarm here, you want the least number of points of failure...
Traditionally a fire alarm would hard cut power to the amps, having it control a shutdown sequence could lead to it a situation where the alarm has already been sounding for some time before the other system has shut down enough to be able to hear it.

So yeah, were it me, I'd be having it as the NC contact controlling the coils of some relays that cut the mains feeds.
Alternately, you could cut the amp outputs rather than the mains feeds.

 

[Edrick]

I was told "connect our relay wire to your power sequencer" the system shuts down within 5 seconds of the sequence being tripped. Most theatrical venues I've been in also trip the sequence and don't just hard cut power. Basically I was asked to have it working by Monday for them. I'm just trying to see if anyone else has experience with the best method of using the sequencer to power off. This'll be the first cafe I've seen that actually shuts down the sound system in a fire event.

 

[AudJ]

Don't know if this will help, but we have 2 different set-ups as ideas. Our cafeteria has a unit for ducking installed, so if emergency systems activate, whatever sound present is muted, and the system remains powered for the school P.A. to come through on a separate channel.

Our new auditorium system is going to have a contact closure unit to the DSP, which will essentially do the same thing by changing a preset, but also activates power to the amps if they are off. You can still use the P.A. for directions in an emergency.

 

[museav]

I would tell the alarm company to pound sand. In the case of an emergency you may need to be able to communicate with the audience to give direction for evacuation.

This has been discussed numerous times and that is 100% wrong. Unless a system is specifically approved for voice evacuation and life safety use then during an emergency the goal is to ensure that any other audio systems will not potentially interfere with the life safety systems. You also want to avoid the possibility of someone making announcements that could just make things worse. It may be fine to use the house audio system for many types of announcements and even some relating to some types of 'emergencies' (lost children, evacuation due to weather conditions and so on) but in most cases it should not be used during actual life safety situations unless the entire system is approved specifically for that use.

Exactly what will be required as far as muting or disabling the house system will vary based on the interpretation of the AHJ. Some may require muting the speakeers or powering down the amplifiers, however tying into a power sequencer is one common approach. You probably do need to make sure that tying into the one sequencer actually disables the system.

The PS-8R allows maintained contact on or maintained contact off operation, however any of the maintained contact remote modes apparently prohibit using the front panel switch or momentary remote operation, so if you want to keep local power control functionality you might have to get creative. For example, set the PS-8R for "REM to +12V = ON" or "REM to GND = ON" mode and wire a second local power switch or relay in series with the NC life safety relay. That way both the local switch and life safety relay have to be closed in order to turn the system on while either opening will turn it off.

 

[BillConnerFASTC]

Sorry museav - I must disagree with you on this one and so does the Life Safety Code. I'm not surprised if local authorities have led you to believe differently.

12.3.4.3.6 The announcement shall be permitted to be made
via a voice communication or public address system in accordance
with 9.6.3.9.2.

and

9.6.3.9.2* Where permitted by Chapters 11 through 43, automatically
transmitted or live voice announcements shall be
permitted to be made via a voice communication or public
address system that complies with the following:
(1) Occupant notification, either live or recorded, shall be
initiated at a constantly attended receiving station by personnel
trained to respond to an emergency.
(2) An approved secondary power supply shall be provided
for other than existing, previously approved systems.
(3) The system shall be audible above the expected ambient
noise level.
(4) Emergency announcements shall take precedence over
any other use.

It is simply the case that the products manufactured by the fire alarm companies and the people that design those systems are not up to providing intelligible announcements in a large space. They don't make line arrays in red and able to withstand heat and fire. Further, it's proven over many incidents and many years that a person - for instance Eddie Foy in the Iroquois Theatre 110 years ago - is much better using equipment they are use to and familiar with than a cheap mic in a box on a cord backstage. For emergencies in large assemblies, live, real time announcement from someone with training and information is required and pre-recorded messages - especially if they can be understood - and horns will be a disaster. The fire alarm industry regularly tries to remove this and I just as often have successfully debated against them. They of course want the additional business but it's simply a case of you can't understand what is being said from those little metal speakers in metal boxes on the wall in a really big room.

I hope the original poster (or that venue) never has a real problem with a full house. You need qualified people, not computers and electronics, when an earthquake, fire, tornado, terrorist, or who knows what occurs in the middle of a large assembled mass of people.

 

[museav]

I don't think that we disagree, however I do think it is more complex than presented. I believe that a house system may be able to serve for life safety and voice evacuation use and theoretically may be the most suited system for that purpose, however I also believe that the system components, performance and operation all need to be appropriate for such use. I know of very few house systems that are electronically supervised, that consist of components UL approved for such use, that during an alarm mute or disable all system audio sources other than emergency related inputs, that mute or overrride all other potentially interfering audio sources (including any life safety system audible signaling devices), that automatically set the system to provide a predefined output level during an alarm or that operate off emergency power or some other form of backup power. There are some systems that have been designed and approved for various voice evacuation and mass notification uses, however I think you'll find few existing house audio systems that meet all of the applicable requirements for such use.

Related to Life Safety Code and NFPA, as I understand it fire (alarm), tornado and terrorist (mass notification) potentially represent three different situations and associated requirements. I believe that one can use any system for announcements related to weather or similar situtations as those are not 'alarm' situations. Alarm situations seem to get into Life Safety Code 101 while Mass Notification may involve NFPA 72-2010 (all for the US, different standards will apply elsewhere). If NFPA 72-2010 applies then that involves the system being designed and verified to meet specific performance criteria relating to level and intelligibility.

The first time I know of someone trying to apply the STI-PA/CIS criteria now in NFPA 72-2010 in conjunction with using the house audio system for life safety announcements apparently ended up with the system as tested not meeting all of the intelligibility requirements and thus being one of the primary causes delaying obtaining a Certificate of Occupancy, a situation which as I understand it from multiple of the parties involved led to having to redesign and install a significantly different audio system and multi-million dollar settlements by the related Architects, Engineers and Consultants. Apparently one of the issues involved was parties other than the audio systems designer, and without their knowledge or input, making 'Value Engineering' revisions to the room finishes, thus altering the acoustical environment in a manner that at least contributed to the resulting system performance being less than expected. But the point is again that not every house audio system, even ones that work acceptably for normal use, may meet the requirements for certain emegerncy announcement uses.

Many of the AHJs I have spoken with seemed to want only trained first responders making discretionary announcements during an alarm situation or people they have approved reading messages they have also approved. I can also see employees or representatives of a venue making discretionary announcements representing a potential liability for the venue, so probably also something to discuss with your insurer before implementing any such policy or practice.

 

[BillConnerFASTC]

Just to be clear, the notification system for a fire alarm in an assembly occupancy with more than 300 occupants does not have to meet NFPA72. That is what the exception is.

As far as AHJs wanting only trained first responders making announcements, could be. The Life Safety Code requires trained crowd managers in all assembly occupancies, and perhaps that qualifies as a first responder. If not, that's too bad as there are many situations where the first responder might not be there fast enough. From detection of a fire to when the room becomes untenable is not many minutes so a rural school, especially one in an area with an all volunteer fd, will not be well served.

The challenge is to have qualified and trained people on site whenever occupied. Some states - like Rhode Island - have made this a priority and have developed training programs for crowd managers.

 

[Edrick]

I'm just not really sure why they required a cafe to have the system tied in, but in the end it is all done and working. I just connected their contact to the 12V+REM and made it so that the contact has to be closed for the system to be able to power on and you just use the sequence rocker switch to turn on or off the system but it will only function when the alarm has the contact closed.