Intro to Conventional Fire Alarm Systems

Introduction to

Conventional Fire Alarm Systems

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Intro to Conventional Fire Alarm Systems

Course DescriptionThis two-hour introductory course is for individuals with little or no experience in the fire alarm industry. The course covers the basic building blocks of modern conventional and addressable fire alarm systems. u It covers the primary and secondary functions of a fire alarm control panel, various initiating and notification devices, digital communicators, waterflow alarm and sprinkler monitoring.u

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Intro to Conventional Fire Alarm Systems

Course Contentsu u u u u u u u u u

Basic Elements of a Fire Alarm System Supplementary Functions Physical Elements of Fire Initiating Devices Notification Appliances Water Flow and Sprinkler Monitoring Types of Control Panels Design Issues Notification Appliance Circuit (NACs) Supplementary Circuit Wiring3

Intro to Conventional Fire Alarm Systems

What is the purpose of a Fire Alarm System?Detect, Alert and Evacuate. Life Safety!4

Intro to Conventional Fire Alarm Systems

Basic FireLets examine the components that make a basic Fire Alarm Control System.

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Intro to Conventional Fire Alarm Systems

Main Controlleru u

The brains of the system. Provides power to the system, monitors inputs and controls outputs through various circuits. Performs other functions as required by the appropriate code.6

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Intro to Conventional Fire Alarm Systems

Elements of a Control PanelMain Controller, Power, Inputs and Outputs

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Intro to Conventional Fire Alarm Systems

Elements of a Control PanelRequires two Power Sources

Primary (AC)

Secondary (DC)8

Intro to Conventional Fire Alarm Systems

Elements of a Control PanelInputs

A fire alarm system can have a variety of input devices.

Smoke Detector

Manual Pull Station

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Intro to Conventional Fire Alarm Systems

Inputsu

Initiating Device A system component that originates transmission of a change of state condition, such as a smoke detector, manual fire alarm box, supervisory switch, etc.... Initiating Device Circuit (IDC) A circuit to which automatic or manual initiating devices are connected where the signal received does not identify the individual device operated.10

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Intro to Conventional Fire Alarm Systems

Elements of a Control PanelOutputs

Horns

Strobes

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Intro to Conventional Fire Alarm Systems

Outputsu

Notification Appliance A fire alarm system component such as a bell, horn, speaker, light, or text display that provides audible, tactile, or visible output, or any combination thereof. Notification Appliance Circuit A circuit or path directly connected to a notification appliance.12

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Intro to Conventional Fire Alarm Systems

The Basic SystemMain Controller Inputs

Primary (AC)

Outputs Secondary (DC)13

Intro to Conventional Fire Alarm Systems

Supplementary Operationsu u u u u u u u

Elevator Capture Equipment Shutdown Air Handling Shutdown Damper Control Extinguishing System Interface Event Printing Display Monitor Interface Door Holding Devices14

Intro to Conventional Fire Alarm Systems

Supplementary Operationsu

Remote Signal Annunciation - Provides critical system status and basic control capability from a more convenient location than where the control panel might be located.

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Intro to Conventional Fire Alarm Systems

Remote AnnunciatorsRZA-5X Remote Zone Annunciator LCD-80F Liquid Crystal Display Graphic Annunciator (Custom)

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Intro to Conventional Fire Alarm Systems

DACTsUDACT Universal Digital Communicator Transmitter

Integral Onboard DACT

411UD Slave/Stand Alone DACT

Dedicated DACT "daughterboard"

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Intro to Conventional Fire Alarm Systems

Basic Fire Alarm TechnologySignal Initiation & Initiating Devices

What is the threat?

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Intro to Conventional Fire Alarm Systems

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Intro to Conventional Fire Alarm Systems

How do we detect the threat?

Automatic Fire Detectors

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Intro to Conventional Fire Alarm Systems

Automatic Fire Detectorsu

Spot Detectors provide detection concentration in a particular location - Heat & Smoke Detectors. Line Detectors provide continuous detection along a path - Thermal Cable & Beam Detectors. Air Sampling Systems draw air through pipes to an enclosed chamber for testing. - (VESDA & Duct Detectors.21

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Intro to Conventional Fire Alarm Systems

Automatic Fire Detectorsu

Photoelectricu u

Light-Scattering (Reflective) Light-Obscuring (Beam)

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Ionization Thermal (heat) Duct

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Intro to Conventional Fire Alarm Systems

Photoelectric Smoke DetectorsLight-Scattering Type These detectors use a Light-Emitting Diode (LED) that sends a beam of light into a dark chamber. A photo diode sits on the other side of a partition within the chamber. u Smoke particles entering the chamber deflect some of the light rays into the photocell. The photo cell generates a current when exposed to light, and if the current reaches a certain level, the smoke detector alarms.u23

Intro to Conventional Fire Alarm Systems

Light Scattering PrincipalSensing Chamber

Light Emitting Diode Partition

Photo Diode

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Intro to Conventional Fire Alarm Systems

Light Scattering Principal

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Intro to Conventional Fire Alarm Systems

Photoelectric Smoke DetectorsLight Obscuration Typeu

In a projected Beam Detector, alarms are generated by diffusing the projected light beam by a specified percentage of obscuration. Total beam blockage generally results in a trouble signal. Wire the receiver unit as a 4-wire detector (separate power and sensing connections to the control panel).26

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Intro to Conventional Fire Alarm Systems

Projected Beam Principal

Transmitter

Receiver

Smoke from the fire in the protected area diffuses the intensity of the beam at the receiver27

Intro to Conventional Fire Alarm Systems

Ionization Smoke DetectorsThese detectors contain a small amount of radioactive material encapsulated in a metal chamber. Ionizing radiation develops a low, but steady electrical current. Smoke particles entering the chamber disrupt the current and trigger the detector's alarm.u

Ion detectors react more quickly to fast flaming fires that give off little smoke.u u

Spot-type Detectors.

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Intro to Conventional Fire Alarm Systems

Duct Detectorsu

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Photoelectric detector mounted in housing outside the ductwork that has probes that extend into the duct to sample the air inside the duct. Primarily used as a smoke control device to control the flow of air in ductwork.29

Intro to Conventional Fire Alarm Systems

The i3 SeriesThis line of photoelectric smoke detectors by System Sensor consists of 2- and 4-wire detectors, offered with or without a fixed 135 temperature thermal sensor. The i3 series is based on three guiding principles: Installation ease, Intelligence, and Instant inspection. uPlug-In Head/Base combination. uSmoothing algorithms uDrift compensation (automatically adjusts for dust accumulation, reducing nuisance alarms) uOptional Sensitivity Reader30

Intro to Conventional Fire Alarm Systems

Manual Initiating DevicesThe Manual Fire Alarm Pull Station31

Intro to Conventional Fire Alarm Systems

Initiating DevicesManual Fire Alarm Stationsu

Manually operated device used to initiate an alarm signal.u

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Single Action Stations require a single operation to activate it. Generally a pulling down action. Dual Action Stations require two distinct operations. A set-up and an activating action. Breakglass Stations have an inhibit device that must be damaged to activate the station (non-ADA compliant).32

Intro to Conventional Fire Alarm Systems

Initiating DevicesManual Fire Alarm Stationsu

Optional Features u With and without key locks or hex key locks u Weatherproof models with special backboxes u With auxiliary contacts u Multiple languages, even dual languages. u With a pre-signal feature u With screw-terminal or pigtail connections u Conventional and Addressable u Metal or Polycarbonate33

Intro to Conventional Fire Alarm Systems

Single-Action Manual StationSpring-loaded releasing switch

Reset Key

Actuation Handle34

Intro to Conventional Fire Alarm Systems

Dual-Action Manual StationInitial Pre-Actuator Actuator

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Intro to Conventional Fire Alarm Systems

Non Alarm Pull Stations

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Intro to Conventional Fire Alarm Systems

Heat DetectorsHeat detectors are the oldest type of automatic fire detection device. Not considered direct Life Safety devices, these detectors do contribute to the detection of a fire.37

Intro to Conventional Fire Alarm Systems

Heat DetectorsFixed Detectors alarm when the sensing element reaches a certain set point. Two common ones have 135 and 200-degrees F range. The Fixed element is generally a non-restorable type, and when activated, must be replaced. u Rate-of-Rise Detectors respond when the rate of temperature increase is greater than an allowable limit (15 degrees in 60 secs.) (placement in a stable environment) (e.g.. ovens, heating vents, etc.). The Rate-of-Rise element i