3. Main Controller
• 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
3
4. Elements of a Control Panel
Requires two Power Sources
Primary
(AC)
Secondary
(DC)
4
5. Elements of a Control Panel
Inputs
A fire alarm
system can
have a variety of
input devices.
Smoke Detector
Manual Pull Station
5
6. Inputs
• 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
6
8. Outputs
• 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.
8
10. Basic Fire Alarm Technology
• Signal Initiation/Initiating Devices
Need to understand stages of fire and
what technology works best for each
10
11. The Stages of a Fire
• Stage One
Incipient: Products of Combustion
particles are produced (<0.3 microns).
No visible smoke or detectable heat.
May occur for milliseconds or days.
• Use ionization detectors
11
12. The Stages of a Fire
• Stage Two
Smoldering: Visible smoke particles are
produced (>0.3 microns). Little visible
flame or noticeable heat.
• Use Photoelectric Detectors
12
13. The Stages of a Fire
• Stage Three
Flame: Rapid combustion produces
radiant energy in the visible, and invisible
(IR, UV) spectrums. Heat begins to
buildup at this stage
• Use Spark or Flame Detectors
13
14. The Stages of a Fire
• Stage Four
High Heat: Uncontrolled combustion is
caused by the heating of nearby
combustibles to their ignition point.
• Use Heat Detectors
Note! Major disadvantages of using
thermal energy for fire identification are
• Takes a while for a fire to be recognized
• The toxic gases that are produced before an
alarm point is reached
14
16. Photoelectric Smoke
Detectors:
Light-Scattering Type
• Uses a Light-Emitting Diode (LED) that
sends a beam of light into a dark chambera photo diode sits on the other side of a
partition within the chamber
• Smoke particles entering the chamber
deflect some of the light rays into the photo
cell. The photo cell generates a current
when exposed to light, and if the current
reaches a certain level, the detector
alarms.
16
17. Photoelectric Smoke Detectors:
Light Obscuration Type
• 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.
17
18. Ionization Smoke 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.
• Ion detectors react more quickly to
fast flaming fires that give off little
smoke.
18
19. Heat Detectors
• Fixed Detectors:
Alarm when the sensing element reaches a certain set
point.
Two common models have 135 and 200-degrees F
range.
Fixed element is generally a non-restorable type, and
when activated, must be replaced.
• 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 is restorable when conditions
return to normal.
• Rate Compensation will respond regardless of the
rate of temperature rise.
19
20. Duct Detectors
• 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.
20
21. Initiating Devices
Manual Fire Alarm Stations
• Manually-operated
device used to initiate
an alarm signal
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.
21
23. Audible Devices
• Bells: Used if they are
only for fire, or have a
distinctive sound from
other bell signaling
devices. Often used as
an external gong to
indicate the flow of
water in the sprinkler
system.
• Horns: Loud and
distinctive output.
Often used in highnoise environments,
such as manufacturing
plants.
23
24. Audible Devices
• Sounders: Electronic or
mechanical audible devices,
which are capable of producing a
variety of tones. Often, the tone
is selectable during installation of
the device.
• Chimes: Soft-toned appliances
used where loud noises could be
disruptive to other operations.
Generally used where qualified
personnel are continuously in
attendance.
24
25. Audible Devices
• Sirens: Extremely loud
devices generally
limited in use to
outdoor or heavy
industrial areas.
• Speakers: Audible
devices used in
conjunction with voice
evacuation messages.
Life-Safety speakers
are not generally
associated with Muzak
systems.
25
26. Visual Signaling
Appliances
Visual signaling appliances are
used in high-noise environments,
in areas occupied by hearingimpaired individuals, or in areas
where audible devices may not be
desired.
26
29. Types of Fire Alarm
Control Panels
• Conventional (hard wired)
Fixed
Programmable
• Addressable (multiplexed)
• Intelligent (analog data transfer)
29
30. Conventional “Hard Wired”
System
• Simplest type of control unit.
• Generally, a single circuit board contains power
supply, control, initiating and notification circuitry.
• Some models use auxiliary circuit boards to
perform special functions.
• Input/output devices connect to dedicated circuits.
• Designated outputs occur when initiating signals
are received.
• Limited special functions and capabilities.
30
31. Conventional “Programmable”
System
• Basic “Designed System”
• Components selected by the designer to
meet the direct needs of the customer.
• Initiating circuits are programmable for fire,
waterflow, supervisory service, etc.
• Output circuits are programmable for code
selection and silenceability.
• On some systems, input-to-output CIRCUIT
(not device) mapping.
31
32. Addressable System
• Each device (detector, pull station…) has a unique
number assigned to it called the address for
reporting alarms and troubles.
• Employs a Signaling Line Circuit (SLC) Loop along
which all addressable input and output devices are
connected to the fire alarm control panel.
• Addressable devices transmit an electronic
message back to the Control Unit representing
their state (Normal, Alarm, Trouble) when polled by
the Control Unit.
32
33. Analog System
• Always an Addressable System.
• Processes detailed, analog data from
detectors about smoke levels.
• Can provide sensitivity data for each
detector.
• Employs Drift Compensation (self
calibration) in its detectors.
33
34. Terminology
•
•
•
•
•
•
•
•
•
•
•
•
FACP - Fire Alarm Control Panel.
FACU - Fire Alarm Control Unit.
FCC - Federal Communications Commission
UL - Underwriters Laboratories
NFPA - National Fire Protection Agency.
AHJ, LAHJ - Authority Having Jurisdiction, Local AHJ
ADAAG - Americans with Disabilities Act Accessibility
Guidelines.
PoC - Products of Combustion
LED - Light Emitting Diode
IDC - Initiating Device Circuit
NAC - Notification Appliance Circuit
ELR, EOL - End of Line Resistor
34
35. Terminology
•
•
•
•
•
•
•
•
•
•
•
•
NEC - National Electrical Code (NFPA 70)
NEMA - National Electrical Manufacturing Association
EIA - Electronics Industry Association
Cd - Candela
dB, dBA - Decibels
FWR - Full Wave Rectified
ANSI - American National Standards Institute
PIV - Post Indicator Valve
OS&Y - Outside Stem and Yoke Valves
SFPE - Society for Fire Protection Engineers
Shall - Indicates a mandatory requirement
Should - Indicates a recommendation or advisement
35
36. References
•
•
•
•
•
•
•
NFPA 70 - National Electrical Code
NFPA 72 - National Fire Alarm Code
NFPA 101 - Life Safety Code
National Electrical Code Handbook, NFPA
Life Safety Code Handbook, NFPA
Fire Protection Handbook, NFPA
Fire Alarm Signaling Systems, NFPA
36
37. Basic Fire Alarm
Technology
Please visit
www.farenhyt.com for fire
alarm system solutions
for your facility
Silent Knight :: 7550 Meridian Circle :: Maple Grove, MN 55369 :: 800-328-0103
37
Editor's Notes
Nicknames for the main controller. Main Board, Main Controller, Motherboard, Central Processing Unit (CPU) Also includes a user interface (keypad) and locked enclosure.
A fire alarm system can have a variety of output devices
This is it for a basic system. Anything else that might be needed is considered "SUPPLEMENTARY"
Smoke obscures a normal linear path of light. Complete and solid blockage from say a ladder will generate a trouble. Beam detection may provide more cost effective solutions to point detection over long distances, especially when the buildings are relatively tall, or where excessive height excludes the use of point detection. Applications include large production facilities, warehouses, ceiling voids, above false ceilings, open areas of shopping malls, churches, aircraft hangers.
Sometimes these devices are considered to be supervisory in nature rather than alarm. Why? Does an HVAC system run all the time? Remember that smoke inside the duct will be diluted, inducing a delay in response time for detection of an alarm.
Notification Appliances are made for four of the five senses - hear, see, touch, smell (but not taste).
Chimes - Used for PRIVATE MODE applications
The DC siren shown (Federal Signal) gives off 127 dB at 100 ft!
The history of fire alarm development - basic "no frills" panel through programmability, addressability and now intelligence.
A system that is said to be INTELLIGENT or ANALOG has capabilities like those listed here. Top-of-the-line systems can make decisions about alarm conditions by using data from one or more input devices.
This presentation includes a large number of acronyms and abbreviations. Let’s introduce some of the more common ones now.