Why Won't the Horns and Strobes Work?
-- When running the continuity check, the panel has to send voltage out on the wires. However, the horns and strobes can't be sounding off. To solve this, the panel reverses the polarity on the circuit to make sure the horns and strobes can't sound off when they aren't supposed to...Read More
How Do I Connect Two Fire Alarm Panels Together?
-- Whether it is one addressable and one conventional panel, or two panels of any sort, there is one issue that has to be dealt with before anything else is taken care of. The issue is that someone untrained and not you are not going to be there to reset the system when there is a false alarm. This is a given, and this is the problem that has to be addressed when using two panels to cover the same building...Read More
How Do You Troubleshoot a Shorted NAC?
-- First off, we have to understand what a NAC (Notification Appliance Circuit) is: it's the wiring outside the fire alarm panel that goes to the horns and strobes, (the notification appliances - the devices). The circuit is a pair of wires that connects all the devices in a chain fashion, like a single strand of beads on a necklace. ... Read More
How Can I Feel More Secure when Working on Fire Alarms?
-- The first thing you do when you arrive on site is to inform those in charge that you are there and that there is a real possibility that the alarms will sound off. Never sugar-coat the explanation, it always is a possibility. Let management know that sounding off the alarms can't always be helped, but you are going to try to prevent that from happening...Read More
Should I Replace the Smoke Detector if it is 80% Dirty?
-- Inside the detector is a computer that senses how much light is reflected over a 24 hour period, and averages that amount. It then adjusts the smoke detector to be less sensitive, so only dangerous smoke suddenly entering the chamber will be considered dangerous smoke...Read More
How Can I Find this Intermittent Ground Fault?
-- A ground fault is an electrical leakage to building ground on a fire alarm system. The ground faults are most commonly in the wiring. Devices themselves, unless there's water damage, are usually electrically isolated so they won't be the cause of a ground fault. The ground fault shown on the panel can be caused by...Read More
How do I Wire a Replaced Tamper Switch?
-- There are two ways to wire a tamper switch. Th old fashioned -trouble- method, and the new Code acceptable -supervisory- method. The first thing to do is figure out how this one is wired...Read More
Who is Supposed to Remove an Old Fire Alarm System?
-- Rather than relying on anyone else to remove an old fire alarm system so a new fire alarm system could be installed, the company I worked for always removed the no-longer-used-fire alarm system. As far as the National Fire Protection Association (NFPA) goes, however, even having a fire alarm system in the first place is the owner's responsibility. The owner only uses a fire alarm company for installation, testing, servicing, and replacement of the fire alarm system. As well as removing any old panels, devices, and wiring...Read More
Will a Trouble on a Device Sound the Alarm?
-- Do you mean by Alarm Signal, a Fire Alarm that gets everybody out of the building, shuts doors, shuts down the air handlers, stops industrial processes, etc.? The answer to what happens when an input or output device goes into trouble is a little less clear...Read More
Am I Allowed to Power Up on the Battery?
-- Powering up a panel using only battery backup is a manufacture's design issue. Some manufacturers have fail-safe features that prevent a panel from turning on until utility power is applied; some manufacturers don't bother with the fail-safe features and allow the panel to be powered up using the batteries...Read More
What Causes a Fire Alarm System Trouble?
-- The word Trouble on a fire alarm system means -In the Fire Alarm System, including all the Input and Output Devices, Signal and Power Wiring, and Panels, something is not working correctly-. This is based on the absolute need for the fire alarm system to Detect Fire and Warn People of Danger. A trouble can be caused by...Read More
Can I Reset a Smoke Detector using Magnets?
-- For test purposes, the first detector sets the panel into alarm, but the next detector tested will not set the panel into alarm because the panel is still in alarm. If you are testing just the smoke detectors and want to know whether they...Read More
How Can I Tell if the Batteries are Bad?
-- When I first checked the batteries they read 12.65 Volts and 22 Amp Hours. I checked the batteries with a battery tester, not a multi-meter. After the low amp hour reading, it was recommended they replace the batteries due to low amp-hours. According to NAPA 72...Read More
How do I Fix a Damaged Loop?
-- When troubleshooting, the exact number of troubles aren't the important part - the fact there are any troubles is the important part. Keep in mind there may be many real troubles that have to be fixed one at a time, or there may be only one trouble causing the panel to detect many -troubles-...Read More
How do I Find this NAC Trouble?
-- The panel is looking at voltage on the NAC circuits - you need the meter to see the voltage that the panel is seeing. When there's no fire alarm on the NAC circuit, there are three voltages possible: Normal, Shorted, Open. These are relative voltages and the only way of telling if the voltage is correct is to compare the NAC 2 voltage to the NAC 1 voltage...Read More
Is There a Code Saying the NAC Can't be in Conduit with the SLC?
-- The contractor wants to run the NAC and SLC circuit in the same conduit distance is about 13 feet. Is this allowable? Or must the two circuits be in different conduits? I looked in NFPA 2016 Chapter 12 and found nothing prohibiting running them together. However, my colleague said it is not permissible but he didn't tell me what reference in the code dictates this. What am I missing?...Read More
How do I Connect a Tamper Switch?
-- When connecting sprinkler tamper switches or sprinkler waterflow switches, I have found that the best way to make sure the system is going to work correctly is to not use the labels on the switch inside the tamer switch assembly. Half of the time those labels are wrong. Those labels are for any system, sort of, and not just for fire alarm systems. Instead, use the Ohmmeter to figure out which screw terminals to use...Read More
What Voltage Should Be at the EOL of a NAC?
-- The goal, when measuring the voltage on the Notification Appliance Circuit -NAC-, is to make sure that there is enough voltage to turn on all the horns and strobes when there is a fire. The power may be off to the building during a power blackout, but the voltage still has to be there for the horns and strobes to warn people of fire...Read More
What is Causing a Network Fault?
-- A Network Fault is a problem (Trouble) with the fire alarm system. The fault has to be fixed before it can be cleared from the panel. To clear the trouble from the display, there's also a trouble memory that requires the troubles to be acknowledged and cleared after fixing the trouble...Read More
How is the Sensitivity of a Smoke Detector Determined?
-- To determine how much smoke it takes to set a smoke detector into alarm, sensitivity testing uses a calibrated, portable cloud chamber. It uses a photo-reader, kind of like the smoke sensing chamber inside a photo smoke detector, to sense the amount of smoke in the cloud chamber. The cloud chamber, or testing tool, completely encloses the smoke detector and starts out with clean air. For the measurement, artificial calibrated smoke is slowly introduced into the chamber...Read More
How do I Fix an Open Fault?
-- The fire alarm system is supposed to consist of the wiring in the building, all of the input devices -smoke detectors, pull stations, waterflow switches, etc.- and all of the output devices -fire horns and strobes, etc.- Between all of the input zones and output zones is a control panel. There should be an end-of-line resistor at the end of each loop -the pair of wires connected to a zone and connected to all of the devices on the zone-...Read More
What does Open Zone Alert Mean?
-- An Open Zone Alert on a fire alarm panel shows that the wire is not continuous. The fire alarm system, being a life safety system, is always checking the wires to make sure the devices like smoke detectors or pull stations are connected at all times...Read More
Is This an Addressable 4 Wire Speaker/Strobe?
-- A speaker and a strobe are always separate devices. Many times, as with the speaker/strobe that you show, the speaker and the strobe my be in the same box, but they are still separate devices, they aren't connected together inside. In this case, this is not an addressable device. On the back of the speaker / strobe, there are 4 terminals: 2 of the terminals are for the speaker and two of the terminals are for the strobe. In other words, the terminals aren't for a single 4 wire addressable circuit, but the terminals are for two completely separate 2 wire circuits: 2 of the wires are for powering the strobe and 2 of the wires are for powering the speaker...Read More
How do you Troubleshoot an Addressable System?
-- No matter what the panel says, or what a multimeter says, all faults are either an open or a short. Both causes could be in the building wide fire alarm system at once, and there may be more than one problem to contend with. Shorts could be inside a device, in the building wiring, or in the panel- opens could be inside a device, in the building wiring, or in the panel. A ground fault is a short, and ground faults require two shorts in order for a ground fault to affect the fire alarm system. At all times when troubleshooting, keep an open mind. Never assume that you know what the problem is until the problem is fixed...Read More
How do Pathways Affect Ground Faults?
-- Ground Faults are a big issue. Almost anytime there is a ground fault on a fire alarm system, the panel displays a trouble. Then, no matter what caused the trouble, the trouble has to be fixed. However, the NFPA has an exception to the rules regarding the displaying of ground fault troubles. For all types of pathways for signal or power in building wide fire alarm systems, the rule of thumb for displaying a ground fault trouble goes something like this, -Whenever there is a ground fault, the panel will display a trouble.- There is an exception to this rule ...Read More
Horns and Strobes for Handicap Apartments
-- Multifamily dwellings like apartments, condominiums, hotel rooms, etc., actually have two fire alarm systems: each individual residence's fire alarm system and the building's common fire alarm system. A fire alarm system, any fire alarm system, detects ... Read More
Why Do We Inspect Fire Alarm Systems?
-- A long time ago, before regular testing of fire alarm systems was required, the NFPA and other fire protection professionals discovered that large numbers of fire alarm systems just weren't working... at all. Originally, when they were installed, these systems worked properly ... Read More
Troubleshooting Addressable Ins and Outs
-- A fire alarm system's main purpose is to detect fire and then tell people about the fire. A conventional fire alarm system does this detection-telling, and so does an addressable fire alarm system. Besides a better display on the addressable fire alarm system and the extension of the ... Read More
Quadruple Use of the Initiating Device Circuit (IDC)
-- In a fire alarm system, the Initiating Device Circuit (IDC) is an input circuit or detection circuit: it carries the alarms detected by devices like flow switches, pull stations, heat detectors, tamper switches, etc. A second use of the Initiating Device Circuit is to monitor itself, it supervises its own wires... Read More
I'm Having Trouble With a Door Release
-- While trying to trouble shoot why the door release for the front door is not working, one of the conductors grounded out against the fire alarm panel chases. This caused the door release to activate. Any thoughts? Read More
What Causes an Open NAC?
-- I am going to a job site where on the service call ticket states that a NAC is reading open circuit. What can cause an open circuit on the NAC line? Read More
How many T-Taps are Allowed on an SLC?
-- The answer to the question of how many T-Taps is allowed --- is It Depends. It depends on the manufacturer and it depends on how easy the installer wants to make the system for the technician... Read More
What is an As-Built Plan?
-- The owner of the building project is the beginning of the planning process and the end of the planning process. Conception Plans - How the building ... Read More
What is a Ground Fault?
-- With the exception of the ground fault circuitry inside the fire alarm control panel (FACP) itself, the wiring for fire alarm systems has... Read More
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