System Sensor BS5839 manual Intelligent Fire Alarm Systems

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Alarm Systems

1.INTELLIGENT FIRE ALARM SYSTEMS

1.1. INTRODUCTION

Conventional fire alarm systems provide an adequate and cost effective fire alarm system for many small buildings. In larger, more complex buildings however, more sophisticated ‘intelligent’ fire alarm systems tend to be used. These systems offer benefits in speed of detection, identification of the location of a fire and easier maintenance. Intelligent systems also offer tolerance to faults in the system wiring, which allows a single pair of wires to be used to connect up to 198 devices to the system, allowing cost savings in the wiring of large systems. In larger installations, the benefits of improved maintenance and reduced cabling cost are overwhelming. Currently, the point at which an intelligent system becomes economical is around 6 zones in the UK.

This guide is intended as an introduction to the technology used in intelligent fire alarm systems. For more information on conventional systems, refer to System Sensor’s ‘Guide to Conventional Fire Systems’.

1.2. INTELLIGENT SYSTEM TYPES

There are two methods commonly used for implementing intelligent fire systems:

The most common type of system is “Analogue”. In this case the detector (or sensor) returns a value to the panel representing the current state of its sensing element(s). The control panel compares this value with the alarm threshold in order to make the decision as to whether a fire is present. Note that the term analogue, used to describe these systems does not refer to the communication method (indeed many “analogue” fire systems use digital communications) but to the variable nature of the response from the detector to the control panel.

In “Addressable” type intelligent systems, mainly used to meet the requirements of the French market, detector sensitivity is programmed to each device by the control panel or is preset in the factory. The detector compares its current sensor value with the configured threshold to make the alarm decision, which is then transmitted to the panel when the sensor is interrogated.

Intelligent Fire

FIRE ALARM SYSTEM OK 28 January 2004 14:01

SYSTEM OK

FIRE ALARM

FAULT

SYSTEM RESET

INTELLIGENT FIRE ALARM CONTROL PANEL

ISOLATOR

CONTROL

MODULE

CONVENTIONAL

ALARM ZONE

ISOLATOR

MONITOR

MODULE

CONTACT

(E.G. SPRINKLER

SWITCH

ISOLATOR

EOL

EOL

In many systems the features offered by the two detection techniques are so similar that it is not particularly relevant which technique is used to make the alarm decision. It is better to select a system based on the features offered by the system as a whole.

1.3. COMMUNICATION PROTOCOL

Intelligent systems use the same pair of wires both to supply power to the loop, and to communicate with devices on the loop. The communication language, or protocol used varies from manufacturer to manufacturer, but generally comprises switching of the 24V supply voltage to other voltage levels to achieve communication.

+24V

Panel to detector

Detector Response

 

Figure 1.1.1 Intelligent Fire Alarm Systems

Figure 1.1.1 demonstrates an example of a single loop intelligent fire system layout. The wiring is looped, and connects to the control panel at each end. All detectors, call points, sounders and interface modules are wired directly to the loop, each having its own address. The control panel communicates with each device on the loop, and if an alarm or fault condition is signalled, or if communications are lost with one or more detectors, the appropriate response is triggered. The loop can be powered from each end so that if the loop is broken at any point, no devices are lost. In addition the use of short circuit isolators minimises the area of coverage lost in the case of a short circuit.

Detector

Control

ErrorCheck

Device

TestStatus

Sensor

Other Info

Type

Value

e.g. drift

Address

 

 

 

 

status

 

 

 

 

 

 

 

 

 

Figure 1.3.1 Typical Protocol Configuration

A typical basic protocol comprises two main parts (See Fig 1.3.1): A query or poll of a device by the control panel including the device address and control information, and a response from the device giving its status and other information. Precise details of the information transferred will depend on the manufacturer, but normally will include:

Poll: Control Panel to device:

•Device address

•Control of device LED - blink to indicate polling, switch on when device is in alarm

•Control of device self-test

•Control of module output

•Error detection for example parity bit or checksum Response: Device to Control Panel

•Device type (e.g. optical detector, heat detector, multi- sensor detector, module)

•Analogue Signal - i.e. the current sensor value

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Note: This document is based on the recommendations of BS5839 Part 1: 2002. It is intended only as a guide to the application of fire detection systems.

Reference must be made to relevant national and local standards.

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Contents Guide to intelligent fire systems Guide to Intelligent Fire Alarm Systems ContentsGuide to Intelligent Fire Alarm Systems Intelligent Fire Alarm Systems Alarm SystemsIntelligent Fire Decimal address switches System Fault ToleranceAddressing Methods Dedicated address programmerPRE-ALARM Facility Intelligent Fire Alarm SystemsFire System Zones Programming of Intelligent Fire Alarm Panels Remote LedsInterface Modules Advantages of Intelligent SystemsGuide Detector Application GuideFire System Categories Category M SystemsApplication Guide Manual Call Points 1. Manual Call Point PositioningSelection of Automatic Fire Detectors Fixed temperature detector 58C Rate of rise heat detectorAreas subject to rapid changes During normal useLocation and Spacing of Automatic Fire Detectors Ceiling HeightDetector type To EN54-7 10.5m Heat detector conforming toCorridor being 7.5m and 5.3m respectively CorridorsSloping Ceilings Location and Spacing of Optical Beam Detectors Lantern LightsVoids and False Ceilings Audible Alarm Signals Visual Alarm SignalsMaintenance of Fire Detectors Codes and standards in the UK BS5839 Part 12002, SectionSeries 200 Plus Features General SpecificationsIntelligent Product Range Series 200 Plus Analogue Addressable Detector RangeWeight System Sensor Intelligent Product Range2251EM Photoelectric Smoke Sensor 2251TEM PHOTO-THERMAL SensorDrift Compensation and Smoothing 5251REM, 5251EM and 5251HTEM Heat SensorsRemote Test Switch 6500S Beam DetectorWeight 142g Operating Temperature -10C to 55CLaser Detector With LED blink enabled 2251EIS Intrinsically Safe Detector and IST200 InterfaceB500 Series Bases Weight 100g Interior diameterExterior diameter DepthM200 Series Module Range M200XE Short Circuit Isolator ModuleSpecifications Max Standby Current, externally powered zone M201E Output Module5A at 250VAC M210E-CZ Conventional Zone ModuleAccessories Call PointsIndoor Indoor products are generally rated at IP24DAudio Visual Products Detector Base SoundersSounder Strobes Majority of back box formatsOther Information Other Information Approval Bodies for Fire Detection ProductsAvenue Hoch Paris, France Tel +33 1 53 89 00 Jernholmen DK-2650 Hvidovre Denmark Tel +45 36 349System Sensor Fire Detectors Volochaevskaya Str 40, BldTelephone + 7 095 Telephone + 91 124 Fax + 7 095

BS5839 specifications

System Sensor BS5839 is a standard that pertains to fire detection and alarm systems, providing guidelines for the design, installation, and maintenance of these essential safety tools. It is crucial for safeguarding lives and property, ensuring that fire detection systems are effective and reliable. The BS5839 standard, established in the UK, covers a wide range of fire alarm system types, including conventional, addressable, and wireless systems.

One of the main features of BS5839 is its comprehensive classification of fire detection systems. The standard divides systems into categories based on the level of risk and the environment in which the system will operate. This classification helps ensure that the system installed meets the specific needs of the building and its occupants. For example, Category L systems are meant for life safety, while Category P systems are designed to protect property.

The technologies underpinning BS5839 include various types of detectors, alarm devices, and control panels. Smoke detectors, heat detectors, and multi-sensor detectors are prominent among the devices specified in the standard. Smoke detectors use photoelectric or ionization principles to detect smoke and signal an alarm, while heat detectors respond to temperature changes. Multi-sensor detectors combine both smoke and heat detection technologies to provide a more reliable response to fire conditions.

Another key characteristic of BS5839 is the emphasis on regular testing and maintenance. The standard outlines procedures to ensure that systems remain operational and effective over time. This includes routine system checks, functional testing, and more in-depth inspections at regular intervals. Ensuring that systems are maintained according to BS5839 is vital for compliance with insurance requirements and for safeguarding against potential legal liabilities.

Furthermore, BS5839 highlights the importance of staff training and awareness. It emphasizes that personnel responsible for fire safety must be adequately trained in the operation and response to fire alarm systems. This ensures that in the event of a fire, occupants are prompted to take appropriate action and evacuate safely.

In summary, System Sensor BS5839 provides a crucial framework for fire detection and alarm systems. Its classification of systems, incorporation of advanced technologies, and emphasis on maintenance all contribute to enhanced safety and compliance, protecting lives and property effectively.
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