Don’t Let EOL Stand for End of Life

Security company owners and managers well know the importance of their jobs. But I often wonder if security and fire technicians fully appreciate the importance of how they do it. Whether it’s security or life safety, the stark truth is lives are often at stake. And from my own personal observation, far too many technicians fail to fully appreciate this fact.

Let’s put it this way, if a manager makes a mistake on a profit and loss form, it might cause some problems, but it is not usually a life and death issue. However, if a fire or burglar alarm technician makes a mistake, it can result in the loss of lives, as well as property.

In terms of fire, in 2004 alone, 3,900 people needlessly died and 17,785 were injured as a result of fire. An unbelievable 83 percent of all fire deaths took place in the home, and an estimated $9.8 billion was lost due to property damage.

Fix Mistakes Before You Leave!
In my distant past, I owned a full-service alarm firm — from 1974 through 1986. For a good part of this time, I did most of the fieldwork myself.

One day, as he noted the complexity of my work, a client asked me, “Do you ever make a mistake?” My simple reply was this: “Sure, but I make sure I find any problems before I leave.” In other words, I checked my work to made sure it worked.

For a time, between magazines, I also worked in the field managing a low-voltage firm. I assisted in the appraisal, hiring and firing of technicians. During my time in this capacity, an exceptionally bright fire alarm technician came to work for us. He had worked for a relatively large national firm and his ability to learn new systems and software programming was phenomenal. The problem was he would become bored when working on relatively small systems. This would lead to complacency, which resulted in mistakes.

For example, one day a restaurant client called with a problem. The notification appliance circuit (NAC) in a commercial-grade combination fire/burglar alarm panel failed to trigger when a fire inspector pulled the manual release on a hood fire suppression system. I paged the technician in question and asked him to drop whatever he was doing and go to the restaurant to look at the problem.

I stopped by the restaurant later to check on his progress. He explained that there really wasn’t a problem and that he had simply forgotten to reconnect the horn/DACT board when he was last working on the system. Evidently, he did not want to disturb the patrons during his extensive tests.

Well that is actually a big problem, which occurred during his previous visit a month or two prior. Obviously, he failed to conduct a working test on the system before he left that original service call. The moral of this story is that security and fire technicians must always check their work before calling it a day — no matter what’s on the schedule that evening.

Avoiding RJ31X-Related Mistakes
It was lunchtime when I received a call on my cell from an out-of-state AHJ. He had a situation where a building burned to the ground, and the fire alarm panel failed to alert the central station. He wanted to know if he could ask me a few questions about RJ-31X jacks. “Of course,” I replied.

It seems the alarm company that installed the system told him the DACT was unable to dial out because of a shorted cable on one of the inside phones. The alarm firm hired another alarm company to come in and check its work. The explanation remained the same. His question was, “If the RJ-31X jack is doing its job, would a short on an inside phone line stop the dialer from dialing out?” I told him, “Of course not.”

The moral of the story is AHJs are getting smarter every day. They may not be technicians, but many of them are doing their homework. This one had read some of my early work on the infamous telephone jack, and he suspected both firms were not telling the truth.

OK, perhaps the technician who did the original installation simply made a mistake. Hey, we’re all human, right? However, as I said, before a technician leaves the jobsite, he or she must be absolutely sure the system works, including signals to the central station.

EOL Resistors Go at End of Circuit
Another common mistake made by a staggering number of security dealers and a handful of fire technicians is the placement of end-of-line (EOL) resistors at the beginning of the line and not at the last device.

“Believe it or not, I’ve found a few fire alarm systems out there where the original installer placed the EOLs inside the panel instead of at the last device,” says Nick Markowitz, owner of Markowitz Electric Protection in Verona, Pa.

“I have seen a good number of burglar alarm systems where the EOLs were installed in the box. When this happens, the panel is not capable of determining when an alarm condition or damaged wire occurs,” says Joe Brosch, vice president with Eagle Systems of Akron, Ohio.

The question is why do these professionals insist on putting them in the panel instead at the end of the line?

I, for one, have written about these issues in years past, but instead of seeing a decrease in this technological tactic I have seen more and more of it.

How EOL Resistors Work
So, why is it so important that EOLs go at the end of each initiating circuit in fire and burglar alarm systems? “Because EOLs provide circuit integrity,” says Brosch. “If a short or open should occur between the panel and [alarm device], the EOL enables the panel to determine that this event has taken place.”

“In a fire alarm system, I suppose a fire technician could place the EOL in parallel with the outgoing Class B loop on the motherboard’s terminal strip,” Markowitz says. When it comes to burglar alarm systems, however, security alarm installers routinely do it. Amazingly enough, many of them vigorously defend the practice.

Let’s talk burglar alarms for a moment. There are two conditions we worry about when an EOL is installed inside the panel. The one involves a criminal’s attempt to sabotage the system and the second involves physical damage to the wire.

When a burglar skins back the insulation on the two conductors in a wire feeding a door switch, for example, if he places a jumper over them, with the EOL inside the panel, the system is blinded.

As for fire alarm systems, installing an EOL inside the panel violates NFPA 72 in terms of circuit integrity. If something should happen to one of the conductors, the motherboard will not know it. There will be no trouble signal to alert the occupants or the alarm company central station. Even more disconcerting is the fact there would be no ensuing alarm to warn anyone.

For the complete version of this story, see the July issue of Security Sales & Integration magazine.

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