New ‘Cable Modem POTS Lines’ Threatens Fire Alarms

I love technology, with all its newness and the new capabilities. At times, I even love the smell. Once in a while, we all have one of those “what the heck?” moments when we question the logic behind a technology change. In the end we usually don’t have a choice, but changes in one area often dictate changes in another.

First and foremost, I want to be clear. In today’s world, internet is being delivered via fiber or cable modem, depending on the need. At Roundbrix, we deploy more fiber than cable to businesses to have fully appreciable symmetrical and guaranteed bandwidth.

sipPhone lines on the other hand, are delivered in a variety of forms. From the newer SIP (Session Initiation Protocol), to its predecessor PRI (Primary Rate Interface or Voice T-1) to the original POTS (Plain Old Telephone Service) lines, which are the analog predecessor commonly utilized for older or smaller phone systems. More importantly, these analog lines have always been used for both burglar and fire alarm lines due to their reliability and non-susceptibility to power outages. The legacy POTS lines always used to be powered by the Central Office, also called a CO. Here, a copper pair of 24 AWG with 48VDC running through it 24 x 7 makes it RELIABLE. It’s also one of the reasons you never wanted a phone near a bathtub as dropping a permanently powered DC electric source could lead to electrocution. But for a fire or burglar alarm, it was perfect. No matter what happened, including a localized power outage for days on end, these central offices always had power and backup power so you could rest assured these important lines would always be able to dial out should there be a fire or burglar-related emergency. For those of us ‘slightly older folks’ remember that the power might go out at our house, but we were always able to use our land lines regardless. This was built into the design on purpose.

Now for the bad news. In a move to be more efficient, and in also considering superseding aging copper, it appears they have made a major blunder. You see, the power backup on a cable modem is only good for a couple hours, four at the most. What this means is if power goes out and no one is at facility beyond the few hours the cable modem might hold it, your fire alarm cannot dial out! Then it’s up to who sees the fire and calls 9-1-1, meaning a lot more property damage could occur, not to mention possible loss of life as a result. In my opinion, these lines from the service provider should be deployed with a clear understanding of the risk with a way to hedge the risk, which is my next point.fire

Here’s the best solution. Purchase an external UPS unit, typically a 1500 VA system. This unit could add another day or so of power to the POTS lines provisioned through the cable modem. If you need more time, then bump up to a 2200 VA system. This is extremely important for businesses that do not occupy the building during nights and weekends, short of mentioning those three or four days for longer weekends like Thanksgiving and Christmas. Here is a link to an APC 1500 for $200 and a link to an APC2200 for $900. In keeping with best practice for UPS units when installed, put a ‘born on’ date on the top and replace it after three years, or more frequently if power outages are more frequent.

Getting one of these units would be a small price to pay to get to greatly mitigate property damage and you may just save a life!

EdSignature

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