FIRE ALARM SYSTEM

A fire alarm system is an integrated life-safety system designed to detect fire conditions, process alarm and fault signals, notify building occupants and interface with other emergency systems according to the programmed sequence of operation. A typical system combines automatic detectors, manual call points, a Fire Alarm Control Panel (FACP), alarm notification devices, interface modules, power supplies and standby batteries.

In a typical operating sequence:

Detector / MCP → Initiating Circuit or Addressable Loop → Fire Alarm Control Panel → Cause-and-Effect Logic → Sounder / Strobe / Interface Output

Fire alarm systems in Nepal are commonly installed in offices, hospitals, hotels, schools, warehouses, factories, shopping complexes and other commercial or industrial facilities. Depending on the building size, required alarm-location accuracy and integration requirements, the system may use conventional fire alarm panels or more advanced addressable fire alarm panels.

Safelincs Tech supplies different fire alarm systems and detection equipment in Nepal, including panels, detectors, manual call points, sounders, modules and standalone smoke alarms.



How Does a Fire Alarm System Work?
A fire alarm system continuously supervises field circuits and devices for normal, alarm, supervisory and fault conditions. Its exact operation depends on whether the architecture is conventional or addressable.

The basic sequence is:

A smoke detector, heat detector or manual call point changes state.

The detector circuit or addressable loop communicates the condition to ​the FACP.

The control panel processes the input according to its programmed logic.

The panel identifies either the affected zone or the exact addressable device.

Notification outputs activate sounders, bells or strobes.

Programmed relays or modules can execute approved emergency functions such as AHU shutdown, magnetic-door release or elevator recall.

Alarm, fault and supervisory events are displayed and, where supported, stored in the event log.

1. Fire Detection
Automatic detection devices respond to different fire signatures.

Photoelectric smoke detectors typically use optical light-scattering technology. Smoke entering the sensing chamber changes the amount of light reaching the optical receiver, allowing the electronics to determine whether the smoke level exceeds the detector's alarm threshold.

Heat detectors respond to temperature rather than smoke. Fixed-temperature models operate when their sensing element reaches a predetermined temperature, while rate-of-rise detectors respond to a rapid increase in temperature.

Beam smoke detectors monitor the reduction of an optical beam across a relatively long distance and are commonly considered for large open spaces, warehouses, halls and high-ceiling areas.

Multi-sensor detectors combine two or more sensing parameters, such as smoke and temperature, and may use internal algorithms to improve fire discrimination.

Where manual initiation is required, manual call points allow an occupant to manually generate a fire alarm condition.


2. Signal Processing
In a conventional fire alarm system, multiple initiating devices are normally connected to an Initiating Device Circuit or IDC. The panel supervises the circuit and determines which zone has entered the alarm or fault state.

A supervised conventional circuit commonly uses an End-of-Line device or resistor (EOL) at the electrically furthest point. Depending on the panel design, different electrical conditions can represent:

normal circuit

alarm

open-circuit fault

short-circuit fault

In an addressable fire alarm system, compatible detectors, MCPs and modules communicate digitally with the panel through a Signaling Line Circuit (SLC) or manufacturer-specific addressable loop.

Each field device has a logical address. The panel polls or communicates with these devices and can identify an alarm as a specific device rather than only a general geographical zone.

Addressable systems may also use:

input/monitor modules

output/control modules

relay modules

zone monitor modules

loop isolators

sounder modules

interface modules


3. Alarm Notification
Once the panel validates an alarm input, notification circuits are activated according to the programmed cause-and-effect sequence.

Notification appliances can include:

sounders

hooters

bells

strobes

sounder-strobes

voice evacuation interfaces

A conventional notification output is often referred to as a Notification Appliance Circuit (NAC). The panel supervises the circuit for wiring faults and supplies the required alarm voltage/current when evacuation notification is initiated.

Addressable systems can also use individually addressed sounders, strobes and notification devices, depending on the system protocol.


Main Components of a Fire Alarm System
A complete fire alarm system equipment list normally includes the control equipment, initiating devices, notification appliances, interfaces, cabling and secondary power supply.

Component

Technical Function

Fire Alarm Control Panel

Processes alarm, supervisory and fault signals and controls outputs

Smoke Detector

Detects products of combustion using optical or other sensing technology

Heat Detector

Detects fixed-temperature and/or rate-of-rise heat conditions

Manual Call Point

Provides manual initiation of a fire alarm

Sounder/Hooter

Generates audible evacuation notification

Strobe

Provides visual alarm notification

Control Module

Provides controlled output to compatible external equipment

Monitor Module

Monitors contact/status inputs from external systems

Relay Module

Provides programmed relay switching

Isolator Module

Isolates a short-circuited section of an applicable addressable loop

FACP Power Supply

Converts incoming mains power to the operating DC supply

Standby Battery

Maintains operation during primary power failure

Fire Alarm Cable

Carries power, signal and communication circuits

Device compatibility is particularly important. Addressable devices normally use manufacturer-specific protocols, so a detector or module should not be connected to an addressable panel solely because the operating voltage appears compatible.


Types of Fire Alarm Systems
The main types of fire alarm systems differ primarily in the way field devices communicate with the control panel and how precisely the panel identifies an alarm location.

1. Conventional Fire Alarm System
A conventional fire alarm system divides a building into geographical detection zones.

Typical architecture:

Detector / MCP → IDC Zone Circuit → Conventional FACP → NAC → Sounder

Several detectors and manual call points may share one zone circuit. When one device activates, the panel displays the affected zone, but it does not normally identify the exact detector.

For example:

ZONE 01 – Ground Floor
ZONE 02 – First Floor
ZONE 03 – Second Floor

The engineer or emergency responder must then inspect the indicated zone to locate the activated device.

Conventional systems generally include separate:

IDC detection circuits

NAC sounder circuits

auxiliary relay outputs

supervised power supply

battery charging circuit

They are often practical for smaller or less complex buildings where the number of zones is limited. Safelincs offers 2-zone, 4-zone, 6-zone and 8-zone conventional fire alarm panels, subject to model availability.


2. Addressable Fire Alarm System
An addressable system communicates with individually identified field devices.

Typical architecture:

Addressable Detector / MCP / Module → SLC Loop → Addressable FACP → Programmed Outputs

Each compatible device is assigned an address such as:

Loop 1 – Address 027 – Smoke Detector – Electrical Room

If that device enters the alarm, the panel can display the specific programmed location.

Compared with conventional architecture, this provides:

exact device identification

more detailed fault localisation

programmable input/output relationships

event logging

easier system expansion

device-status monitoring

advanced cause-and-effect programming

The addressable loop may supply both communication and operating power to compatible devices, although the topology, polarity, loop length, cable specification and maximum device loading depend on the manufacturer.

For larger projects, explore addressable fire alarm panels, addressable smoke detectors and compatible addressable MCPs, sounders and modules.


3. Wireless Fire Alarm System
Wireless fire alarm systems replace part or all of the field communication cabling with supervised radio communication.

Typical architecture:

Wireless Detector / MCP → RF Communication → Gateway/Panel → Alarm Outputs

Important engineering considerations include:

radio coverage

signal attenuation

battery supervision

interference

repeater requirements

device polling

communication fault monitoring

Wireless architecture can be useful in retrofit projects, heritage buildings and locations where installing new fire-resistant cabling would be difficult.


Conventional vs Addressable Fire Alarm System
The main technical difference is not simply price. It is the method of circuit supervision, device identification and system communication.

Technical Factor

Conventional

Addressable

Alarm identification

Zone

Individual device

Detection circuit

IDC/zone circuit

Addressable SLC/loop

Communication

Electrical circuit state

Digital device communication

Device address

No individual address

Unique logical address

Fault localisation

Circuit/zone

Device or loop section

Wiring architecture

Multiple radial zones

Loop/radial as manufacturer permits

Programming

Basic

Advanced

Cause-and-effect

Limited

Highly programmable

Event history

Model-dependent

Commonly available

Loop isolation

Not normally applicable

Available in suitable systems

Scalability

Moderate

High

Typical application

Small/medium premises

Medium/large/complex premises

Initial system cost

Generally lower

Generally higher

For a small building with limited detection zones, a conventional fire alarm system can provide a cost-effective solution.

For hospitals, hotels, multi-storey complexes, industrial plants and other sites where exact alarm identification or extensive integration is important, an addressable fire alarm system normally provides greater flexibility.


Fire Alarm System Architecture
A fire alarm system can be divided into four functional layers: initiation, processing, notification and interfacing.

1. Initiating Devices
Initiating devices generate or report an alarm or supervisory input.

Examples include:

smoke detectors

heat detectors

beam detectors

flame detectors

manual call points

sprinkler water-flow switches

valve supervisory switches

third-party dry-contact inputs

Safelincs provides both conventional smoke and heat detectors and individually identified addressable smoke detectors.

2. Control Equipment
The Fire Alarm Control Panel (FACP) performs the central processing functions.

Its functions may include:

IDC supervision

SLC communication

NAC control

alarm verification logic

input/output mapping

system reset

acknowledge and silence functions

event logging

battery charging

ground/earth fault monitoring

communication with repeater panels

programmable relays

3. Notification Devices
Notification devices communicate the fire condition to building occupants.

These include:

sounders

hooters

bells

strobes

sounder-strobes

voice evacuation equipment

The notification load must remain within the electrical capability of the panel or approved auxiliary power supply.

4. Interface Devices
Addressable interface modules allow the fire alarm system to exchange signals with other equipment.

Common interfaces include:

monitor/input modules

control/output modules

relay modules

short-circuit isolators

conventional-zone interface modules

supervised output modules

Safelincs currently lists items such as an addressable zone monitor unit and addressable input modules within its addressable MCP, sounder and module range.


Fire Alarm System Diagram and Wiring Architecture
A fire alarm system diagram should distinguish between initiating circuits, notification circuits, addressable loops, power supplies and external interfaces.

Conventional Fire Alarm System Diagram
A simplified conventional architecture is:

Smoke Detector / Heat Detector / MCP
↓
IDC / Zone Circuit
↓
Conventional Fire Alarm Control Panel
↓
NAC Output
↓
Sounder / Hooter / Strobe

The zone circuit is supervised by the FACP. In many conventional systems, an EOL device is installed at the final device to allow the panel to distinguish normal wiring from an open-circuit fault.

Addressable Fire Alarm System Diagram
A simplified addressable architecture is:

Addressable Detector → MCP → Monitor Module → Isolator
↓
SLC / Addressable Loop
↓
Addressable Fire Alarm Control Panel
↓
Programmed Outputs / Sounder / Relay / Interface Module

Unlike a conventional IDC, the SLC carries addressable communication between the panel and compatible devices.

Loop design should consider:

maximum supported device addresses

loop current

cable resistance/capacitance

maximum permitted cable length

isolator positions

branch/topology restrictions

voltage drop

manufacturer protocol

These values should always be taken from the specific panel and device manufacturer documentation rather than assumed from another system.


Fire Alarm Control Panel
The fire alarm system control panel is responsible for supervising field wiring and processing system events.

A modern FACP may monitor:

alarm inputs

trouble/fault inputs

supervisory conditions

AC mains supply

battery voltage

charger condition

SLC communication

NAC continuity

earth/ground faults

network communication

1. Conventional Fire Alarm Panel
A conventional panel normally has a fixed number of detection zones.

For example:

2-zone

4-zone

6-zone

8-zone

Each zone terminal supervises a separate IDC. The engineer should calculate device quantity, current consumption, cable length and panel compatibility before connecting detectors or MCPs.

Safelinc's conventional fire alarm panel range includes different zone capacities for smaller and medium-sized installations.

2. Addressable Fire Alarm Panel
Addressable panels are generally specified according to:

number of SLC loops

addresses supported per loop

detector/module capacity

loop current

network capability

repeater support

programmable outputs

event-log capacity

supported protocol

Safelincs currently lists 2-loop and 4-loop addressable fire alarm panels.


Fire Alarm System Zones and Loops
What Is a Fire Alarm Zone?
A fire alarm zone is a defined area used to help identify the location of an alarm.

In conventional systems, the zone normally corresponds directly with a physical IDC.

For example:

Zone 1 → Ground Floor Detectors
Zone 2 → First Floor Detectors
Zone 3 → Second Floor Detectors

A zone chart placed near the panel can help responders identify the physical area represented by each zone indication.


What Is an Addressable Loop?
An addressable loop or SLC – Signaling Line Circuit connects compatible intelligent devices to the control panel.

The panel communicates with individual addresses such as:

Loop 1 / Device 001

Loop 1 / Device 002

Loop 1 / Device 003.

Device labels should then be programmed with meaningful location text.

Example:

L1 D032 – Smoke Detector – Server Room

Short-circuit isolators can be installed where supported to prevent a cable short from disabling an excessive portion of the SLC.


Fire Alarm Detectors
Detector selection should be based on the expected fire signature and the environmental conditions at the installation location.

1. Smoke Detectors
Photoelectric smoke detectors are widely used for detecting smoke produced by smouldering or developing fires.

Important specifications can include:

sensing technology

operating voltage

standby current

alarm current

sensitivity

communication protocol

operating temperature

humidity range

base compatibility

For individually identified devices, see addressable smoke detectors.


2. Heat Detectors
Heat detection is useful in locations where normal dust, steam or fumes could make smoke detection unsuitable.

Common operating methods are:

Fixed Temperature: alarm activates when the sensing element reaches a specified threshold.

Rate-of-Rise: alarm activates when temperature increases faster than the detector's specified rate.

Safelincs also supplies conventional smoke and heat detectors for compatible conventional systems.


3. Beam Smoke Detectors
Beam detectors use an optical transmitter/receiver arrangement or reflective path to monitor smoke obscuration over a larger area.

Typical applications include:

warehouses

factories

atriums

auditoriums

high-ceiling halls

Beam alignment, building movement, obstruction and mounting height must be considered during design and commissioning.

4. Multi-Sensor Detectors
Multi-sensor detectors evaluate more than one fire parameter, such as optical smoke and temperature.

The purpose is to improve detection decision-making and reduce unwanted alarms where the detector and panel support multi-criteria processing.


Fire Alarm Modules
1. Control Module in Fire Alarm System
A control module in a fire alarm system converts a programmed panel command into an electrical output for compatible external equipment.

Possible applications include:

magnetic-door release

AHU shutdown

fire/smoke damper interface

elevator recall interface

external notification circuit

approved suppression-system interface

The module output may be relay-based or supervised depending on the product.


2. Monitor Module
A monitor module allows the addressable panel to monitor an external contact.

Typical monitored inputs can include:

sprinkler water-flow switch

valve tamper switch

pressure switch

suppression-panel status

equipment fault contact

The module converts the external input into an individually identified addressable event.


3. Isolator Module
An isolator module in a fire alarm system protects an addressable communication loop against short-circuit faults.

When a short occurs, isolators positioned around the affected cable section can disconnect that segment while allowing unaffected sections of a correctly engineered loop to continue communicating.

Isolator quantity and spacing depend on:

manufacturer requirements

loop topology

device quantity

project specification

applicable fire alarm standard


Fire Alarm System Integration
A modern fire alarm system often communicates with multiple building services through programmed relays, modules or approved gateways.

Possible integrations include:

HVAC/AHU systems

access-control doors

elevators

smoke-control systems

fire/smoke dampers

sprinkler supervision

suppression panels

building management systems

public-address/voice evacuation systems.

For example, a programmed cause-and-effect sequence may be:

Smoke Detector Alarm
→ FACP validates alarm
→ Notification devices activate
→ AHU shutdown command
→ Magnetic doors release
→ Elevator recall interface operates

Fire-alarm interfacing with anaccess control and door lock system should be designed so that the required doors assume their specified emergency state during an alarm.

Similarly, a fire alarm system may monitor sprinkler water-flow and valve supervisory switches associated with afire hydrant and sprinkler system.

Life-safety control should not be transferred casually to a BMS. Required fire alarm functions should remain under the control of approved fire alarm equipment and the project's specified cause-and-effect logic.


Fire Alarm System Design Considerations
A reliable fire alarm system design begins with building risk, occupancy and system requirements rather than simply selecting a panel according to the number of detectors.

1. Building Risk Assessment
The design should consider:

building occupancy

floor area

number of floors

escape routes

high-risk areas

ceiling construction

environmental conditions

sleeping accommodation

critical rooms

required system interfaces


2. Detector Selection and Placement
The detector type should match the expected fire signature and environment.

Important factors include:

ceiling height

air velocity

dust

steam

temperature

humidity

room geometry

obstructions

ventilation openings

A smoke detector should not simply be replaced by a heat detector because of nuisance alarms without determining whether the resulting detection performance remains appropriate.


3. Zone and Loop Planning
For a conventional system, design should establish:

zone boundaries

number of devices per zone

cable routes

EOL position

circuit resistance

spare zone capacity

For an addressable system, design should consider:

loop capacity

addresses per loop

device current

isolator locations

loop length

cable parameters

future expansion

module requirements


4. Alarm Notification Design
Sounder and strobe design should consider:

building layout

ambient noise

sleeping areas

enclosed rooms

machinery noise

visual-notification requirements

circuit current

The total notification appliance load must remain within the panel/NAC or approved power-supply capacity.


5. Power Supply and Battery Backup
The FACP normally includes a power supply and battery charger.

A proper power calculation considers:

Standby Load = Sum of all standby device and panel currents

and:

Alarm Load = Panel + detectors/modules + notification appliances + activated outputs

Battery capacity should then be calculated from the required standby and alarm duration under the applicable project standard, with manufacturer-specified factors and battery characteristics considered.


Fire Alarm System Cable and Wiring
Fire alarm cable selection must match the system, project specification and applicable code requirements.

Engineering checks include:

conductor size

circuit resistance

voltage drop

fire resistance

insulation rating

cable capacitance where relevant

polarity

segregation from other services

screening/earthing where specified

1. Conventional Wiring
Typical circuits include:

IDC: detectors and MCPs
NAC: sounders and strobes
Auxiliary circuits: relays and external interfaces

Where required by the panel, the EOL device must be installed at the actual end of the supervised circuit rather than inside the control-panel enclosure.


2. Addressable Wiring
The SLC must comply with the manufacturer's:

cable specification

maximum loop length

conductor-size requirement

resistance limit

capacitance limit

topology restrictions

Addressable products from different brands should not be assumed to communicate with each other merely because they use two wires.


Fire Alarm System Installation
Professional fire alarm system installation in Nepal should follow an engineered process rather than installing devices before completing system design.

Typical workflow:

Site survey

Risk and occupancy review

System architecture selection

Detector and MCP layout

Zone/loop design

Cable routing

FACP installation

Field-device installation

Termination and continuity checks

Device addressing

Location-label programming

Cause-and-effect programming

Functional testing

Fault simulation

Battery and power testing

Commissioning

Documentation and handover

For a complete project, the selectedfire safety equipment should be coordinated with the overall fire-protection strategy rather than treated as isolated products.


Fire Alarm System Testing and Commissioning
Commissioning verifies that the installed system operates according to the approved design.

Testing should include, where applicable:

individual smoke-detector activation

heat-detector functional testing

MCP activation

sounder operation

strobe operation

zone identification

address/location identification

open-circuit fault simulation

short-circuit fault simulation

isolator operation

mains failure

battery operation

charger status

earth/ground fault

input-module activation

output-module operation

cause-and-effect sequence

event-log recording

repeater communication

Every addressable device should be checked against the programmed location description so that the panel does not display an incorrect room or floor during an actual emergency.


Fire Alarm System Maintenance
A fire alarm system requires periodic inspection, testing and maintenance to remain dependable throughout its service life.

1. Routine Inspection
Inspect:

FACP indicators

power status

fault messages

disabled devices

detector condition

MCP accessibility

sounder condition

cable damage

interface status


2. Functional Testing
Representative or required devices should be functionally tested according to the maintenance programme and applicable requirements.

Testing may include:

detector activation

MCP activation

notification

interface outputs

panel reset

fault monitoring


3. Battery Testing
Battery inspection should include:

terminal condition

charging voltage

battery age

physical swelling/leakage

capacity where required

A battery showing normal open-circuit voltage may still have insufficient capacity under load.


Fire Alarm Fault Troubleshooting
Common faults include:

Open Circuit: broken conductor, loose termination or removed device.

Short Circuit: conductors connected together or damaged cable.

Earth/Ground Fault: unwanted connection between system wiring and earth.

Missing Addressable Device: device removed, wiring failure, addressing problem or communication failure.

Duplicate Address: two devices programmed with the same address where the system does not permit it.

Low Battery: deteriorated battery or charger/power-supply problem.

Dirty Detector: contamination affecting detector sensitivity or generating a maintenance warning where supported.

System troubleshooting should identify and correct the root cause rather than permanently disabling the affected zone or device.


Fire Alarm System Standards and Compliance
Fire alarm projects may reference international standards such as NFPA 72, EN 54 product standards, BS 5839 or other requirements depending on the project specification and authority having jurisdiction.

1. NFPA 72
NFPA 72 addresses fire alarm and signaling-system requirements including areas such as:

initiating devices

notification

circuits and pathways

supervising-station systems

emergency communications

inspection

testing

maintenance.

The applicable edition and project requirements should be confirmed before design or installation.

2. UL-Listed Fire Alarm Equipment
UL listing indicates that a specific product has been evaluated against the applicable UL product standard and conditions of use.

For example, different fire alarm equipment may fall under different product standards, so "UL Listed" should be verified for the exact model rather than assumed for an entire brand or product category.

Safelincs currently lists selected products such asNumens fire alarm equipment, including products described by the site as UL-listed. Product documentation should be reviewed when certification is a project requirement.

Actual installation must also consider manufacturer instructions and requirements from the applicable local authority.


Fire Alarm Systems for Different Buildings
1. Fire Alarm System for Offices
Smaller offices can often use conventional zoning, while larger multi-floor office buildings may benefit from addressable device identification.

The design should consider:

open office areas

server rooms

electrical rooms

meeting rooms

exits

Staircases


2. Fire Alarm System for Hospitals
Fire alarm system design for hospitals usually requires more detailed identification and system integration because hospitals contain sleeping occupants, clinical areas, critical equipment and occupants who may require assistance during evacuation.

Design considerations can include:

addressable device identification

zoned/phased notification

smoke-control interfaces

door-release logic

lift interfaces

critical-room detection

fault monitoring

high system availability


3. Fire Alarm System for Hotels
Hotel systems should consider:

guestrooms

corridors

staircases

kitchens

electrical rooms

reception

common areas

Larger hotels generally benefit from exact addressable device identification because identifying the precise room or area can significantly improve emergency response.


4. Fire Alarm System for Warehouses
Warehouses can present detection challenges because of:

high ceilings

large floor areas

storage racks

dust

temperature variation

air movement

Depending on the risk and geometry, the design may consider smoke, heat, beam or specialised detection methods.


5. Industrial Fire Alarm System
Industrial environments may require detectors selected for:

dust

fumes

humidity

high temperatures

hazardous processes

machinery

The system may also require extensive addressable modules for monitoring process equipment and interfacing with emergency systems.


Fire Alarm System Price in Nepal
The fire alarm system price in Nepal depends on system architecture, panel capacity, device quantity, brand, wiring, interfaces and installation requirements.

Current Safelincs product listings provide examples such as:

Fire Alarm Equipment

Example Current Price

Battery Operated Smoke Detector

From around NPR 1,199

Conventional Smoke/Heat Detectors

Around NPR 1,250–2,500 depending on model

Conventional MCP / Hooter

Around NPR 1,650–3,800 depending on model

Addressable Smoke Detector

Around NPR 4,520

Addressable Heat Detector

Around NPR 4,520

Addressable Manual Call Point

Around NPR 5,200

Addressable Sounder & Strobe

Around NPR 5,800

Conventional Fire Alarm Panel

Around NPR 8,500–24,500

Addressable Fire Alarm Panel

Contact for current price

Addressable Modules

Contact for current price

Prices may change depending on brand, model and stock availability.

The complete project cost is more than the equipment purchase price. It can include:

control panel

detectors

MCPs

notification devices

interface modules

isolators

fire alarm cable

containment

installation

programming

testing

commissioning

documentation

A small conventional installation can therefore have a much lower initial cost than a multi-loop addressable project requiring hundreds of devices and multiple building interfaces.


How to Choose a Fire Alarm System
The system should be selected according to technical requirements rather than price alone.

1. Small Premises
A conventional system may be practical where:

the building is small

the number of zones is limited

exact device identification is not essential

few system interfaces are required

Browseconventional fire alarm panels and compatibleconventional detectors.


2. Medium and Large Premises
Addressable architecture is generally more suitable where:

the building has several floors

device quantity is high

exact location identification is important

extensive cause-and-effect logic is required

system expansion is expected

Exploreaddressable fire alarm systems andaddressable detection devices.


3. Residential and Standalone Applications
Where a full FACP-based installation is not required, individualbattery operated smoke detectors can provide standalone local smoke detection for appropriate residential applications.

Final system selection should consider:

occupancy

floor area

number of floors

detector quantity

required location accuracy

future expansion

alarm interfaces

maintenance

project standard

total lifecycle cost


Fire Alarm System Brands Available in Nepal
Safelincs Tech currently lists several fire alarm brands and product ranges.

Numens: Numens fire alarm equipment includes conventional detection and alarm products such as smoke detectors, heat detectors, MCPs and notification devices.

TNA: TNA fire alarm systems include addressable fire alarm equipment available through Safelincs.

Ravel: Ravel fire alarm systems are also available within the Safelincs fire alarm range.

ASES: ASES fire alarm equipment includes fire alarm devices available for different system requirements.

System Sensor: Safelincs also listsSystem Sensor fire alarm products for fire detection applications.

Brand selection should consider protocol compatibility, certification, replacement-device availability, technical support, panel capacity and lifecycle maintenance rather than brand name alone.



Frequently Asked Questions
1. What is a fire alarm system?
A fire alarm system detects fire-related conditions and sends the information to a control panel. The panel then activates notification devices and programmed emergency outputs.

2. How does a fire alarm system work?
A smoke detector, heat detector or MCP sends an alarm through a zone circuit or addressable loop to the FACP. The panel processes the input and activates the required sounders, strobes and interfaces.

3. What are the main fire alarm system components?
The main components are the FACP, detectors, MCPs, sounders, strobes, modules, cables, power supply and batteries. Addressable systems additionally use individually identified field devices and communication loops.

4. What is the difference between conventional and addressable fire alarms?
A conventional panel normally identifies the affected zone, while an addressable panel identifies the individual device. Addressable systems also provide greater programming, fault localisation and expansion capability.

5. What is a control module in a fire alarm system?
A control module provides a programmed output from an addressable fire alarm system to compatible equipment. It can be used for functions such as door release, AHU shutdown or other approved fire-safety interfaces.

6. What is an isolator module in a fire alarm system?
An isolator detects and disconnects a short-circuited section of a compatible addressable loop. This can help maintain communication with unaffected loop sections.

7. What is the fire alarm system price in Nepal?
The price depends on the panel, detector quantity, system type, modules, cable and installation requirements. Safelincs currently lists individual fire alarm equipment from around NPR 1,199, while complete systems can cost significantly more.

8. What cable is used for a fire alarm system?
Fire-resistant cable is commonly specified for fire alarm circuits, but conductor size and cable characteristics depend on the system and applicable project requirements. Always follow the panel manufacturer's wiring specifications and approved system design.

9. What is an SLC in a fire alarm system?
SLC stands for Signaling Line Circuit and is commonly used for communication with addressable field devices. The permitted topology, number of devices and cable length depend on the fire alarm manufacturer.

10. How often should a fire alarm system be tested?
Testing frequency should follow the applicable code, project maintenance plan and manufacturer requirements. Detectors, MCPs, notification appliances, batteries, interfaces and fault monitoring should all be included in the maintenance programme.