Supervision of Wire Loops in the Fire Alarm System
By Douglas Krantz
Fire alarm system (FAS) is a Life Safety System (people’s lives depend on the fire alarm system working in an emergency), using supervision, the panel makes sure the field devices are always connected to the loop. However, supervision isn't just the panel turning on its yellow light and sounding its local buzzer. When trouble occurs on the system, supervision is the owner doing something about the trouble.
To make sure the wiring is supervised, the wires are installed in the form of loops, according to strict standards, designed specifically for fire alarm systems.
- If the panel’s local sounder keeps making noise every 24 hours, for instance, the building management calls for service. That’s supervision.
- If a wire to a door holder breaks, the door won't stay open. The building management calls to get the door holder working again. That’s also supervision.
Fire Alarm Loop = Pair of Wires
In a fire alarm system, a loop is a pair of wires. It carries power and signals between the circuit boards inside the fire alarm control panel (FACP) and the off-panel devices in the field.
As a Power or Control Circuit, carries signals or power to specific fire safety controls and devices
- As an Initiating Device Circuit (IDC), carries signals from the input devices to the panel
- Style B - Class B
- Style D - Class A
- A Notification Appliance Circuit (NAC), carries signals and power from the panel to the fire horns, speakers, and strobes, causing the devices to make noise and flash lights, alerting the occupants of a potential fire. Audible, Tactile, Visible
- Signaling Line Circuit (SLC), carries signals in the form of data between the panel and the input and output devices. Canada calls "Class B Level 1" "Data Communications Link (DCL) Style B"
- Style 4 - Class B 2-wire circuit. Class B circuits do not have redundant path. They simply leave the control unit and terminate at the last device. This is typically utilized for circuits serving building shafts, such as elevator and stair shafts.
- Style 6 - Class A 4-wire circuit
- Style 7 - Class A 4-wire circuit
- Style 7 - Class A 4-wire circuit
IDC (Initiating Line Circuit)
The IDC is a pair of wires without T-taps, connecting the panel to the input sensing devices.
Fire Sensing Input Devices (Alarm)
Smoke Detectors - When a smoke detector senses smoke, it will delay activation by a predetermined amount of time (typically less than 1 minute) then check again to verify smoke detection persists to avoid false alarms
- Waterflow - limited to 5 per zone.
- Flow through a pipe, using a 3-conductor hall effect sensor
Heat Detectors - Heat detectors are slower than smoke detectors but faster than sprinklers (when selected properly). They are not the first choice except in location with extreme temperatures, dust or vapors.
Manual Fire Alarm Box Pull Stations - don't work when building unoccupied and malicious false alarms
Fire Suppression System Alarms
Spot Detector - bimetallic eutectic (mixture of substances (in fixed proportions) that melts and solidifies at a single temperature that is lower than the melting points of the separate constituents) metal leaf spring, fusible alloy, flexible diaphragm or pneumatic tubing rate-of-rise (12 to 15°F per minute)
Flame Detectors - Ultraviolet for Hydrogen fires (almost no IR, 4.4µm not seen), Infrared. Fast —appropriate for fuel loading areas, explosive atmospheres, hyperbaric chambers,
- Ionization type smoke detectors are good for faster burning fires that do not produce a lot of large smoke particles. Uses @Alpha; radiation from Americium-241. Conductance between two charged plates reduced.
- Photoelectric light scattering smokes are good for slower, smoldering type fires that produce larger smoke particles. Photoelectric smokes also tend to be more stable and less susceptible to air movement and higher altitudes.
- Projected Beam
There is no limit to the number of pull stations and heat detectors you can add to a conventional fire alarm panel because the NO contacts draw no current/power.
Mixing IDCs and NACs with different manufacturer’s Panel
Heat detectors and pull stations are usually just normally open, dry contact devices that close when they activate. If this is the case, there is no U.L.
compatibility requirement, and you can use anyone’s device on any panel’s IDC (Initiating Device Circuit) that accepts normally open NO contact inputs.
- No current: A dry contact is the synonym of volt free - it is not “wetted” by a voltage source. A dry contact is totally isolated from the signal or coil so a lot less thought has to go into using such a relay. An ordinary single pole toggle switch has “dry contacts”.
- Secondary set of contacts of a relay circuit which does not make or break the primary current being controlled by the relay.
- A “wet” contact device provides the power to the device you want to control. A Triac is an example. It is NOT isolated in this case. That is why you see a lot of specs calling for dry contacts. There are quite a few manufacturers that don't want voltage in their equipment from foreign sources.
- Yet another explanation ~ “Wet contact” is like a mercury switch, whereas a dry contact is like a relay.
Non-Fire Input Sensing Devices (Supervising other systems)
- Duct Detectors (in older systems these were alarm) - The HVAC Codes require smoke detectors on the supply side of large air handlers. Tube must extend at least 2/3 into duct.
- Most deaths result from smoke inhalation often toxic fumes released by the heat of the fire.
- Fire Suppression System Supervisories
- Fire Pump Supervisories
- Gatevalve Supervisories
- elevator lobby smoke detectors
- elevator machine room (EMR) smoke detectors
- elevator machine room (EMR) heat detectors
- pit smoke detectors
- shaft smoke detectors
- safe floor recall
- alternate floor recall
- fire alarm connection to elevator controls
- elevator power shunt-trip circuit breaker
- shutdown supervision
- powered smoke damper operation
- damper position monitoring
- car alarm and firefighter service indicator (“Red Hat”)
No more than 20-supervisory devices per zone. No more than 22,500 square feet ft2 per zone.
To avoid signal confusion, Fire Sensing (Alarm) and Non-Fire Sensing (Supervisory) devices are not mixed on the same IDC loop.
The panel supervises the fire alarm wiring using an end-of-line resistor. This resistor allows small electrical current to pass through the wires of the loop, making sure the wires and connections are always complete. For a Class B loop, the end-of-line resistor may be in a distant part of the building, or for a Class A loop, the end-of-line resistor is part of the circuitry of the panel.
Digital Alarm Communicator Transmitter (DACT)
Connects to central monitoring station (CMS) which then calls the fire department using a POTS (Plain Old Telephone Service) copper lines connected to a PSTN (Public Switched Telephone Network) with an RJ31X disconnect outlet. 4/2 SIA or contact ID encoding.
NAC (Notification Appliance Circuit)
Wired similar to the Initiating Device Circuit (IDC) Class A or Class B loop, the NAC carries power to operate the "Notification Appliances":
- Fire horns / sounders
- Strobes / flasher. Do not mix different manufacturer’s devices on a circuit if you require strobe synchronization. Both strobes and panel must be UL cross listed together (same for IDCs). Brightness requirements (measured in candelas) depends on room size.
- Remote Annunciators / Speakers - mass notifications iaw NFPA 72 Chapter 18 Audibility Requirements
- Audio (in public mode, sound level of at least 15dB above the average ambient sound level or 5dB above the maximum sound level having a duration of at least 60 seconds, whichever is greater, measured at 5 feet above the floor throughout the covered area.
- 1 pair of 18 awg twisted/shielded wire for the data and a second pair (does not need to be twisted/shielded) for the 24Vdc power.
- areas with an occupancy of 300 or more people, theaters with more than one viewing room, or buildings where an occupied floor is higher than 75 feet above the exit level will require notification by means of either pre-recorded voice messages and/or live announcements, which means you need speakers and a fire alarm panel with the amplifiers and audio source to support them.
Fire alarm device will have a FWR (Full Wave Rectified) and DC current draw rating. Multi-candela strobe devices will have a different current rating for the different candela settings. The AHJ may require worst case design/installation. The minimum circuit voltage rating of the NAC (typically 85% of nominal 24v or 20.4 volts, but refer to panel’s manual for correct value)
If both the panel and device are U.L. listed as Regulated, then they are considered compatible, and may not be on the compatibility sheet.
In the Supervision state (no alarm), a low power electrical current is passed through the entire circuit and either goes back to the panel (Class A) or goes through an end-of-line resistor (Class B). The voltage polarity is reversed. No current flows through the notification appliances because of the diode.
In alarm state, the DC voltage on the loop is forward biased; the electrical current provided by the panel goes through the notification appliances.
Battery capacity required
- Standby time ~ 24 hours)
- Alarm time ~ 5 minutes
Edwards Signals (a UTC subsidiary) EST edwards-signals.com/files/Fire_Alarm_FAQs_v2.pdf
When the fire panel goes into alarm, the panel stops supervising the loop and changes the voltage polarity to normal. Electrical current then goes through the devices, causing the devices to notify the occupants of the building.
Ancillary connections or Fire Safety functions (ANSI A17.1 National Elevator Code elevator recall, fan shutdown, stadium theater lighting turn on)
Door hold opens have a permanent magnet. The fire alarm control unit provides 10 mA at 24VDC to create a magnetic field to cancel the permanent magnet. The spring door-closer operates.
- >THHN conductors installed in EMT indoors and THWN conductors installed in ENT outdoors. Conductors insulated to 600V and conductor size as small as 14AWG, (18AWG and 16AWG are permitted, with restrictions).
- Non-power-limited cable marked “NPLF” (general purpose), “NPLFR” (riser), or “NPFLP” (plenum ceiling), with an overall insulation of 600V and conductor size as small as 18AWG. Imagine Romex® cable.
- Power-limited cable marked “FPL”, “FPLR”, or “FPLP” with an overall insulation of 300V and conductor size as small as 26AWG. Imagine CAT 5 cable.
ANSI A17.1 is the national elevator code, but local codes may be different. You should always refer to the proper codes for your area for exact requirements.
Typically you will need the following:
- a smoke detector located in each elevator lobby;
- a smoke and/or heat detector in the elevator machine room (the heat if there are sprinklers);
- a heat detector located at the top of the elevator shaft (if there is a sprinkler at the top);
- a smoke detector located at the top of shaft (if there is a sprinkler anywhere in the hoist way);
- a set of relays located in the elevator machine room to control the elevators (primary, alternate, shunt);
- a visual warning ("firefighter’s hat") indicating if elevators are unsafe to use;
- and a control panel (the panel can be the building’s fire alarm panel or a dedicated panel if there is no FA panel)
SLC (Signaling Line Circuit)
The Signaling Line Circuit (SLC) carries signals both to and from the panel; it uses data to carry the signals out from the panel to field devices, and data to carry the signals back from the field devices to the panel.
The SLC also provides a small amount of power to operate the field devices.
Field Devices Connected to an SLC
- Smoke Detectors
- Heat Detectors
- Combination Smoke/Heat Detectors
- Pull Stations
- Alarm and Supervisory Input Modules
- Control Relays
- NAC Riser Modules
- 24 VDC Audible
- 24 VDC Visible
- 24 VDC Combination Audible/Visible
- Audio for Speakers (Direct Current (DC) blocking capacitor allows 70.7 VAC 200-20KHz through) independent of other audio.
- Firefighter’s Phone
It is a long-standing requirement that the fire alarm control unit and system must be operational for it to be legal to use a public building. A fire marshall can have a principal of a school arrested if they have a FACP problem and don't begin a Fire Watch, walking the facility every hour, and notify the fire department.
KNOX-BOX Rapid Entry System for Fire|EMS|LEO to access property - used for gates and Apartment buildings. 3501 switch is small.
Addressable Fire-Alarm Control Panel (FACP)
To supervise the SLC
and to make sure all devices are always connected, the panel sends data to each input or output device, polling the device and asking "are you there"? The device then responds with answers by returning data to the panel saying "I am here."
With the constant polling of the field devices, the need to supervise the wiring itself isn't necessary; the "Class B" SLC may be T-tapped. Addressable technology also brings the advantages of T-Tap wiring to a fire alarm system’s output notification appliance component. T-Tapping can save the installer 30% or more in labor and materials. Addressable sensors and notification appliances can be "dead-ended".
As well as the polling of the devices, Class A SLC loops are not T-tapped and are still supervised for wiring issues. Non-addressable appliances require a labyrinth of wires, which take a long time to install and leave many opportunities for errors during installation.
International Code Council (ICC)/ANSI A117.1 (2009): Accessible and Usable Buildings and Facilities
- Sinorix clean-agent releasing
• Building Code
Siemens Building Solutions FireFinder XLS System
- PC-based, color graphics software designed for use with the XNET network, offering full control and annunciation
- SureWire addressable-loop technology
- Polarity-insensitive detection circuits
Siemens HLIM Isolated Loop Circuit Protectors (ICLP)
NFPA 72 National Fire Alarm and Signaling Code (NFAC)
In the 2007 edition, you are no longer given a choice of Styles for Initiating Device Circuits (IDCs), Notification Appliance Circuits (NACs) and the Class B Signaling Line Circuit (SLC).
Now, the IDCs and NACs are simply designated as either Class A or Class B. Period.
This alone dropped 16 Style designations from the three tables. The only choice of Styles remaining is for the Class A Signaling Line Circuit which will be designated as either Style 6 or Style 7. The difference being
- Style 6 No Alarm Receipt Capability (ARC) with a wire-to-wire shortStyle 7 Alarm Receipt Capability (ARC) with a wire-to-wire short or Class X redundant pathway per NFPA 72-2010 version new chapter (12) devoted to circuits and pathways
In 2007 class/style tables were rooted in “copper” wiring methods. 2010 and 2013 updates reflect fiber (no ground faults, shorts, or lightning vulnerability), Ethernet and wireless sensor networks (WSN) digital data radio modem RF comms [WirelessHART | ISA100.11a]
- Class C - LAN/WAN/IP
- Class D - Fail-Safe: wiring that provides power to door hold open devices. Door closes automatically for fire separation
- Class E - not supervised, used with circuits that provide power to an air compressor jockey pump for a large dry sprinkler system
- Class R - redundant circuits that utilize metallic conductors, but are not afforded with ground fault detection.
- Class S - single path supervised circuit that utilizes metallic conductors, but is also not afforded with ground fault detection.
Chapter 12 and 24 Survivability
Level 0 or Level 1 survivability designation. Generally speaking, contractors will use pathway survivability of Level 2 or 3 for in-building fire emergency
- Level 0 pathways have no required survivability. With electronic redundancy through various LAN and WAN networks, Ethernet is a good example of Level 0.
- Pathway Survivability Level 1 consist of pathways in buildings that are fully protected by an automatic sprinkler system in accordance with NFPA 13, Standard for the Installation of Sprinkler Systems, with any interconnecting conductors, cables, or other physical pathways installed in metal raceways. 2-hour fire-rated circuit integrity (CI) cable or similar.
- Rather than just pathway of circuit, entire building is fully protected by a sprinkler system.
NFPA 13, Standard for the Installation of Sprinkler Systems
, with any interconnecting conductors, cables or other physical pathways installed in metal raceways.
UL 2075, Standard for Gas and Vapor Detectors and Sensors. e.g. Carbon Monoxide (CO) sensors.
SDM Access Control, Panels
HART - Highway Addressable Remote Transducer
remote control telemetry: bi-directional industrial field communication protocol between intelligent field instruments and host systems.
- IEC 61804-3
- HART upgraded to Foundation FieldbBus.
- Used in 75% of process industries.
- Two masters possible: primary & secondary
- Bell 202 Frequency Shift Keying (FSK) 1200 bps standard superimposed digital communication signals at a low level on top of the classic 4-20 mA / 0-5 VDC analog control signal across a single pair of wires. Three digital updates per second @ 1.2kbps.
- Fault ≤ 3.75mA, Minimum = 4 mA, Maximum 20mA, Fault > 22mA, HART FF
- 0 = 2200Hz
- 1 = 1200Hz
- 200mV pp minimum FSK voltage, with 1mA pp current so load must be between 230 and 1,100 Ω
- Master Slave Configuration. Master typically a
- Distributed Control System (DCS)
- Programmable Logic Controller (PLC) [real time, ladder logic]
- Emergency Shutdown System (ESD)
- Process Automation System (PAS)
- Plant Asset Management (PAM) / Asset Management System (AMS)
- Handheld Terminal (HHT) / Handheld Field Communicator (HHC) / Programmer (HHP) portable technician tool
- Loop Check
- Set ID of device
- Diagnostics & calibration
- Intelligent Device Management (IDM)
- Production Data Management (PDM) - CAD, BOM, drawings, routings
- Human Machine Interface (HMI)
- Supervisory Control and Data Acquisition System (SCADA)
- Electronic Device Description Language (EDDL)
- Factory Automation & Industrial Control Systems (FA & ICS)
- Motor Operated Valves (MOV)
- Piping and Instrumentation Diagram (P&ID) ≠ Proportional, Integral & Derivative (PID) control
- Adjust OutPut (OP) to move the Process Variable (PV) as quickly as possible to the SetPoint (SP) (responsive), minimize overshoot, and then hold the PV steady at the SP without excessive OP changes (stable).
- Proportional band or P-Gain
- Reset, Integral or I-Gain
- Preact, Derivative or D-gain
- Plant electrician | instrumentation technician replaces PLC modules
- Industrial Automation Leaders Fire Alarms First
- Siemens AG
- Honeywell (Notifier SWIFT wireless mesh & ONYX panels)
- UTC Climate, Controls & Security (CCS includes Kidde, Edwards/EST) in addition to BIM, Carrier HVAC/R, & Otis elevators
- ABB (ASEA Brown Boveri), acquired Thomas & Betts in 2012
- Schneider Electric SA France
- Emerson Industrial Climate Technologies Retail Solutions HVAC, refrigeration, energy monitoring
- Rockwell Automation Allen-Bradley
- Mitsubishi Electric
- General Electric (GE)
- Johnson Controls
- Aspen Tech
- Pass & Seymour
- Simplex TrueAlert addressable fire alarm NACs, IDCs & SLCs
- DITEK Total Surge Solution (TSS)
- Manufacturing Execution Systems (MES), Laboratory Information Management System (LIMS), Warehouse Management System (WMS)
As hardware has become more capable at lower prices market share shifts towards software and services
24 VAC “C” wire from HVAC system
Class II power limited 50 VA
NFPA 1 Fire Code
NFPA 101-2015 Life Safety Code: occupancy classification, egress, sprinklers, alarms, emergency lighting, smoke barriers, carbon monoxide (CO) and special hazard protection in both new and existing structures. Calculate occupant load. NICET Level III.
Fire Protection Handbook
Fire Alarm Signaling Systems
reedconstructiondata.com/building-codes now http://www.constructconnect.com/building-codes/?search=Virginia
• OSHA 1910.164 (Fire Detection Systems)
• OSHA 1910.165 (Employee Alarm Systems)
- building owners
- building managers
- electrical contractors
ANSUL & AMEREX manufacture kitchen grease fire suppression wet chemical systems including dual agent.
ANSUL R-101 (dry chemical) & Ansul X R-102 (wet chemical with foam blanket)
Fusible link melts. Compressed gas
Salamander - food station
Proximity hoods are designed for grease and heat laden effluent (Type I Hood) and are shorter in height and depth than a canopy hood. The name "Proximity" or "Backshelf" refers to the close location of the hood with respect to the cooking equipment.
Exhaust and supply fans
Dry, chemical or gaseous fire suppression systems - Carbon Dioxide CO2, FM200 Halon,
Interlocked dry pipe systems - requires a fusible link to melt the sprinkler head AND electronic detection of fire or smoke in the space which in turn opens a valve upstream of the sprinkler head letting water flow into the system.
A wet sprinkler system is filled with water, with a sprinkler head going off immediately.
Laboratory exhaust systems need to remain in operation to remove toxic products of combustion. This differs from office type ventilation systems that are configured to shut down in the event of a fire.
International Association of Property and Evidence IAPE.org recommends the dry chemical in Data Centers, Server/IT rooms, MDF rooms, MRI equipment, Telecom Rooms, Chemical Labs, Electrical Cabinets, Vehicles, Record Storage, Test Chambers, Utility Vaults, Evidence Labs/Storage, CNC Machines, Grinders, Server Cabinets, Flammable Material Storage and Museums
Fire alarms require initial and periodic ITM
- Certified Automation Professional (CAP)
- ANSI/ISA-95 and IEC/ISO 62264 standard for Enterprise System to Control System Integration
- ANSI/ISA-88 General Recipes
- NEMA ICS 12.1
WirelessHART & ISA100 Wireless both use 16 channels in unlicensed 2.4 GHz band defined by IEEE 802.15.4 Low-Rate wireless Personal Area Networks (LR-PAN) using star or peer-to-peer mesh topologies.
NICET is a division of the National Society of Professional Engineers. Jules NICET # 207182
Fire Alarm Systems (FAS) Certification Standard Model/CBT Application PearsonVUE testing.
- > 3 months of technical experience with fire detection and signaling systems $210, 75 questions, 110 min Study Test
- > 2-years $270
- > 5-years $325
- > 10-years $375, 105 questions
Related experience = low voltage systems, building electrical power or control systems, special hazards systems, or smoke control systems in the role/function of installation, inspection, testing, commissioning, maintenance, technical system estimating and sales, plans preparation, code compliance review, project management, or technical business management.
licensed fire protection engineer
NICET Application Applied: NICET ID:
Society of Fire Protection Engineers,
Fire Protection Engineering PE Exam Online Prep Course
Class A vs Class B IDC wiring
- Normal - sees EOLR
- Alarm - short or smoke/fire, presence of fire danger
- Supervisory - off normal condition, monitoring for integrity
- Trouble - open circuit, wire cut, problem with equipment
- A -
- B - one wire to device with EOLR
NFPA 70 NEC Article 700 Power or Control Circuit
The control circuit
, usually from an on-board relay in the panel, turns on or off devices and systems.
The on-board relays can also be used as part of another panel’s IDC loop, sending alarm, supervisory, and control signals to that other panel. This is particularly useful when the fire alarm panel itself doesn't have an on-board communicator, to provide for off-site monitoring.
The actual wiring may be a little different from the standard IDC, NAC, and SLC loops, but the control loops still have to be supervised for integrity.
Some of the uses for the on-board relays:
Fire Alarm Supervision
All wiring outside in a fire alarm system, whether it’s an IDC, NAC, SLC, Power or Control loop, needs to be supervised, and supervision includes the call for service and repair of the system, once the panel indicates trouble with the system. An analog system may drift and create a maintenance rather than trouble alert.
Renovation, Refurbishment, Remediation, Demolition
Non-linear Insulation Resistance (IR) may require more voltage than a VOM/DMM outputs normally to detect and isolate. 80% of electrical maintenance and testing involves evaluating insulation integrity especially in harsh installation environments: temperature extremes, chemical contamination and rubbing/chafing. Megger. Insulation (dielectric) can be compromised by high-voltage. Protected premise alarm systems must identify open circuits and ground faults within 200-seconds.
Dedicated fans in lieu of environmental fans for smoke control are preferred particularly for elevator and stair shaft pressurization and atriums.
HART is a widely used communication standard for field devices. The HART-Standard expands the analog 4- bis 20-mA signal into a modulated, industry-standard digital HART signal. Device Descriptions (DD) are written using the Device Description Language (DDL) defined in the HART Specifications and referred to in IEC 61804-2
Analog signals drift over time, requiring maintenance to adjust sensitivity or drift. Must be tested after a year following installation then every other year. If stable then every 5-years.,
The advantage is the combination of field-tested analog measured-value transmission and simultaneous digital communication with bi-directional, acyclic transmission, making it possible to transfer diagnostic, maintenance and process information from field devices to higher-level systems. Standardized sets of parameters can be used for cross-vendor operation of all HART devices.
HART Device Descriptions(EED) are used to integrate HART devices in SIMATIC PDM ensuring easy operation and commissioning of field devices even in hard-to-reach locations.
Addressable / Intelligent Sensors
- HI921 - Heat Detector Hea
- OH921 - Smoke Detector
- 8720 Device Programming Unit (DPU)
- OPC - formerly OLE for Process Control
NFPA 72-2013 National Fire Alarm and Signaling Code
Chapter 1 Administration
1.6 Units and Formulas
1.7 Code Adoption Requirements
Chapter 2 Referenced Publications
2.2 NFPA Publications
2.3 Other Publications
2.4 References for Extracts in Mandatory Sections
Chapter 3 Definitions
3.2 NFPA Official Definitions
3.3 General Definitions
Chapters 4-6, 8-9, 11, 13, 15-16, 19-20, 22, 25, 28 Reserved
Chapter 7 Documentation
7.2 Minimum Required Documentation
7.3 Design (Layout) Documentation
7.4 Shop Drawings (Installation Documentation)
7.5 Completion Documentation
7.6 Inspection, Testing, and Maintenance Documentation
7.7 Records, Record Retention, and Record Maintenance
Chapter 10 Fundamentals
10.4 Installation and Design
10.5 Personnel Qualifications
10.6 Power Supplies
10.7 Signal Priority
10.8 Detection and Signaling of Conditions
10.10 Distinctive Signals
10.11 ECS Priority Signals
10.12 Alarm Signals.
10.13 Fire Alarm Notification Appliance Deactivation
10.14 Supervisory Signals
10.15 Trouble Signals
10.16 Emergency Control Function Status Indicators
10.17 Notification Appliance Circuits and Control Circuits.
10.18 Annunciation and Annunciation Zoning
10.19 Monitoring Integrity of In-Building Fire Emergency Voice/Alarm Communications Systems
10.20 Documentation and Notification
10.22 Unwanted Alarms
Chapter 12 Circuits and Pathways
12.3 Pathway Class Designations
12.4 Pathway Survivability
12.5 Shared Pathway Designations
12.6 Monitoring Integrity and Circuit Performance of Installation Conductors and Other Signaling Channels
Chapter 14 Inspection, Testing, and Maintenance
Chapter 17 Initiating Devices
17.3 Performance-Based Design
17.4 General Requirements
17.5 Requirements for Smoke and Heat Detectors
17.6 Heat-Sensing Fire Detectors
17.7 Smoke-Sensing Fire Detectors
17.8 Radiant Energy–Sensing Fire Detectors
17.9 Combination, Multi-Criteria, and Multi-Sensor Detectors
17.10 Gas Detection
17.11 Other Fire Detectors
17.12 Sprinkler Waterflow Alarm-Initiating Devices
17.13 Detection of Operation of Other Automatic Extinguishing Systems
17.14 Manually Actuated Alarm-Initiating Devices
17.15 Fire Extinguisher Electronic Monitoring Device
17.16 Supervisory Signal–Initiating Devices
Chapter 18 Notification Appliances
18.4 Audible Characteristics • Intelligibility: capable of being understood, comprehensible and clear
18.5 Visible Characteristics — Public Mode
18.6 Visible Characteristics — Private Mode
18.7 Supplementary Visible Signaling Method
18.8 Textual Audible Appliances
18.9 Textual and Graphical Visible Appliances.
18.10 Tactile Appliances
18.11 Standard Emergency Service Interface
Chapter 21 Emergency Control Function Interfaces
21.3 Elevator Recall for Fire Fighters' Service
21.4 Elevator Shutdown
21.5 Fire Service Access Elevators.
21.6 Occupant Evacuation Elevators
21.7 Heating, Ventilating and Air-Conditioning (HVAC) Systems
21.8 Door and Shutter Release
21.9 Electrically Locked Doors
21.10 Exit Marking Audible Notification Systems
Chapter 23 Protected Premises Fire Alarm Systems
23.3 System Features
23.4 System Performance and Integrity
23.5 Performance of Initiating Device Circuits (IDCs)
23.6 Performance of Signaling Line Circuits (SLCs)
23.7 Performance of Notification Appliance Circuits (NACs)
23.8 System Requirements
23.9 In-Building Fire Emergency Voice/Alarm Communications
23.10 Fire Alarm Systems Using Tone
23.11 Suppression System Actuation
23.12 Off-Premises Signals
23.13 Guard’s Tour Supervisory Service
23.14 Suppressed (Exception Reporting) Signal System
23.15 Protected Premises Emergency Control Functions.
23.16 Special Requirements for Low-Power Radio (Wireless) Systems
Chapter 24 Emergency Communications Systems (ECS)
24.4 One-Way Emergency Communications Systems Acoustically Distinguishable Spaces (ADS)
24.5 Two-Way, In-Building Emergency Communications Systems
24.6 Information, Command, and Control.
24.7 Performance-Based Design of Mass Notification Systems
Chapter 26 Supervising Station Alarm Systems
26.3 Central Station Service Alarm Systems.
26.4 Proprietary Supervising Station Alarm Systems.
26.5 Remote Supervising Station Alarm Systems
26.6 Communications Methods for Supervising Station Alarm Systems
Chapter 27 Public Emergency Alarm Reporting Systems
27.2 General Fundamentals
27.3 Management and Maintenance
27.4 Communications Methods
27.5 Alarm Processing Equipment
27.6 Alarm Boxes
27.7 Public Cable Plant
27.8 Emergency Communications Systems (ECS)
Chapter 29 Single- and Multiple-Station Alarms and Household Fire Alarm Systems
29.3 Basic Requirements
29.5 Detection and Notification
29.6 Power Supplies
29.7 Equipment Performance
29.9 Optional Functions
29.10 Maintenance and Tests
29.11 Markings and Instructions
Annex A Explanatory Material
Annex B Engineering Guide for Automatic Fire Detector Spacing
Annex C System Performance and Design Guide
Annex D Speech Intelligibility
Annex E Sample Ordinance Adopting NFPA 72
Annex F Wiring Diagrams and Guide for Testing Fire Alarm Circuits
Annex G Informational References
NATIONAL INSTITUTE FOR CERTIFICATION IN ENGINEERING TECHNOLOGIES (NICET)
Pearson VUE CBT. System layout (plan preparation), system equipment selection, system installation, system acceptance testing, system trouble-shooting, system servicing, and system technical sales.
- Fire Alarm Systems certification
- Inspection & Testing of Fire Alarm Systems certification
Application + Testing Costs Certification Levels
Exam Code: 10007 - Fire Alarm Systems, Level I
Applicant’s NICET ID: 207182
Application Date: 6/18/2016
Payment Reference: AU1AE768AAF9
Total Amount Paid: $210.00
The state of Alabama has mandated that electrical contractors can't pull fire alarm (FA) cable or install devices without NICET 2 certification
Engineering Technologist (Installer) 2-year degree with some math & science vs Engineer (Designer/Planner) with lots of math & science, a 4-year ABET-accredited engineering degree & EIT exam & PE accreditation
Virginia DPOR ELE classification includes Fire Alarm Systems (FAS) specialty (50 volts or less). PSI’s $85 VA Fire Alarm Systems Contracting FAS specialty exam (with approval from DPOR) allows highlighted & tabbed NEC & NFASC.
National Fire Protection Association (NFPA)
- NFPA 70 “National Electric Code (NEC)”
- NFPA 72 “National Fire Alarm and Signaling Code”
PSI Exams FAS Questions (35/50 to pass)
Power Supply 5
Alarm Notification 12
General Regulations 5
General Electrical Knowledge 5
Additional Books & Codes allowed in NICET exam
- International Building Code(IBC) for NICET II
- International Plumbing Code (IPC)
- International Fire Code (IFC)
- International Residential Code (IRC)
- International Energy Conservation Code (IECC)
- Fire Alarm Signaling Systems, 4th Edition 2010 $150
- NFPA 101 “Life Safety Code” building exit construction including stairways & fire escapes for factories, schools, apartments, nightclubs, health care, hotels/dormitories, jails; and requirement for fire drills for NICET III
- NFPA 1 Fire Code
NFPA 72-2010 includes Emergency Communication System (ECS) based on Air Force Civil Engineering Mass Notification Systems (MNS) [Ch 24]
circuit pathways [Ch 12],
ECS pathway survivability, ECS secondary power supply and speech intelligibility requirements, far more than just fire hazards --weather alerts and warnings, terrorist attacks, radiological, chemical releases (CBRNE). &mdsash;Biological, Nuclear, Incendiary, Chemical, Explosive (BNICE)
- Inspection of permanent and temporary buildings, processes, equipment, systems, and other fire and related life safety situations
- Investigation of fires, explosions, hazardous materials incidents, and other related emergency incidents
- Review of construction plans, drawings, and specifications for life safety systems, fire protection systems, access, water supplies, processes, hazardous materials, and other fire and life safety issues
- Fire and life safety education of fire brigades, employees, responsible parties, and the general public
- Existing occupancies and conditions, the design and construction of new buildings, remodeling of existing buildings, and additions to existing buildings
- Design, installation, alteration, modification, construction, maintenance, repairs, servicing, and testing of fire protection systems and equipment
- Installation, use, storage, and handling of medical gas systems
- Access requirements for fire department operations
- Hazards from outside fires in vegetation, trash, building debris, and other materials
- Regulation and control of special events including, but not limited to, assemblage of people, exhibits, trade shows, amusement parks, haunted houses, outdoor events, and other similar special temporary and permanent occupancies
- Interior finish, decorations, furnishings, and other combustibles that contribute to fire spread, fire load, and smoke production
- Storage, use, processing, handling, and on-site transportation of flammable and combustible gases, liquids, and solids
- Storage, use, processing, handling, and on-site transportation of hazardous materials
- Control of emergency operations and scenes
- Conditions affecting fire fighter safety
- Arrangement, design, construction, and alteration of new and existing means of egress
- NFPA-780 “Standard for the Installation of Lightning Protection Systems”
Nonpower-Limited Fire Alarm (NPLFA) vs Power-Limited Fire Alarm (PLFA) Circuits"
- Remote-control circuit. These circuits, which control other circuits through relays or equivalent devices , are commonly used to operate motor controllers in moving equipment, mechanical processes, elevators, and conveyors.
- Signaling circuit. These circuits energize signaling equipment  and are typically used to operate a bell or horn, or to illuminate a light in a control panel.
- Power-limited circuit. These circuits are supplied by a source with a rated output of not more than 30V and 100VA [725.21(A)].
Based on NEC's Article 725 Remote-control, Signal, and Power-limited circuits
- Class 1 remote-control and signaling circuits typically operate at 120V, but the NEC permits them to operate at up to 600V [725.21(B)]. A wiring method listed in Chapter 3 of the NEC, which includes raceways, cables, and enclosures for splices and terminations [725.25] is required, the same wiring requirements for power and light circuits, but smaller wire sizes than normal power and light circuits are allowed: No. 16 and No. 18 AWG conductors, protected at 10 amperes maximum for No. 16 AWG and 7 amperes maximum for No. 18 AWG.
Class 1 remote-control circuits are commonly used in motor controllers, bucket control transformers, start/stop stations, signal lights, speed switches, limit switches, elevators, conveyors, and in equipment controlled from one or more remote locations. Class 1 signaling circuits are used in nurses' call systems in hospitals, electric clocks, bank alarm systems, and factory call systems. Class 1 circuits are Non-Power limited, other than by conductor size and over current protection devices (OCPD): 15A for 14 AWG copper, 20A for 12 AWG copper, 30A for 10 AWG copper per 240.4(E) or (G).
Derating Class 1 Circuit
- Class 2 circuits. Due to its power limitations, a Class 2 circuit is considered safe from a fire initiation standpoint and provides acceptable protection from electrical shock. Class 2 circuits typically include wiring for low-energy (100VA or less) for voltages under 30VAC and 60VDC to loads such as low-voltage lighting, HVAC heating/cooling system thermostats, PLCs, security systems, and limited-energy voice, intercom, sound, and public address systems. You can also use them for twisted-pair or coaxial local area networks (LAN) [725.41(A)(4)].
Class 2 circuits may also protect against electrical fires at higher voltages by limiting the power to 0.5VA | 5mA for circuits between 30V and 150V [Chapter 9, Table 11].
You can wire Class 2 circuits with Class 2 cable or any of its substitutes permitted by Table 725.61(A), depending on the condition of use.
- Class 3 circuits. Use Class 3 circuits when the power demand for circuits over 30V exceeds 0.5VA, but is not more than 100VA [Chapter 9, Table 11]. Class 3 signaling circuits are used in security systems and public address systems; voice, intercom, and sound systems; some nurse call systems, and where a Class 2 circuit is routed a distance where voltage drop becomes a problem.
Higher levels of voltage and current are permitted for Class 3 circuits (in contrast to Class 2 circuits). To prevent an electric shock hazard, the wiring must be rated no less than 300V [725.71(E) and (F)]. Wiring methods that meet this requirement include PLTC Cable, Class 3 Cable, or any of its permitted substitutions listed in Table 725.61(A), depending on the condition of use.
Class 2 and 3 systems do not require the same wiring methods as power, light, and Class 1 systems. There are cases when a 2-in. separation is required between these systems.
725.11(A). When a circuit controls equipment that can introduce a direct life safety hazard the circuit shall be Class 1. Class 2 and Class 3 circuits are not allowed! An example of this is the high limit thermostat switch for a boiler. Another is the high level switch on a tank full of flammable vapors. At a refinery located in Valdez, Alaska the entire process control wiring was done using 24 volt Class 2 and intrinsically safe wiring. However, all the high limits and any other safety device that could possibly introduce a catastrophic failure were wired using Class 1 signaling circuits at 120 volts.
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