May 18 2018

Fire Alarm System Communication

Category: BlogBKeyes @ 12:00 am
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The answer to this question was provided by my good friend Gene Rowe, Director of Business Development for Affiliated Fire Systems, Inc., Downers Grove, IL

Q: With the impending discontinuation of the hard copper (POTS) phone lines, and in fact many municipalities already no longer have hard copper pairs from end user to the Central Office, are we, or will we be, in violation of the NFPA code for the primary DACT connection to the CO? Our fire alarm system company is telling us we must upgrade to another form of communication; however we have an IP based phone system in all buildings and the fire alarm company documentation indicates that IP based technology is acceptable, can I simply designate two analog phone lines from our system to the DACT, eliminating the POTS connection?

A: Per NFPA 72 (2010) Chap. 26.6.3.2, Patrick would be code compliant if he continues to use phone lines for a central station connection.  However, if the vendor is saying he must upgrade, it sounds like they’re discontinuing DACT monitoring.  He should verify that with the vendor.  Most central stations have DACT, radio and cellular receivers, but some are discontinuing DACT receiving for the reasons Patrick stated.  If he’s connected to a central station that’s dropping it, he may be able to find a new central station that still has it.  If he’s directly connected to a fire department that’s dropping it, he can see if he’s allowed to use a central station for monitoring.  If they’re not dropping DACT monitoring, he can ride that horse until discontinued by the monitoring agency or the lines die, but I’d advise setting up a new method so he can control the costs before it becomes an emergency.

Switching to IP based phone lines would still use the existing DACT transmitter, but without getting too technical, it comes with a couple of conditions:

  1. There has to be a dial tone on the IP phone lines when the receiver is picked up (loop started).  If you have to dial a number to get a dial tone (ground started), you can’t use it.
  2. The DACT communication out of the fire panel must now be converted into IP packets at the source, then reassembled into digital signals at the receiver.  That means the central station must have an IP converter & the end user must install an IP converter that matches it.
  3. The power for the phone system must be backed up by the emergency generator.

Obviously, bullet #2 is where the costs comes in & it won’t be cheap.  It may seem like it shouldn’t be a big deal, but changing communication methods always involves new equipment.  The costs & legwork involved in staying with phone lines may be more than installing the upgrade, which is probably a radio.

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