Firesense Linear Heat Detection
Analogue and digital cables, interfaces and accessories
Firesense Linear Heat Detection
Early and precise detection of heat over long distances
Firesense Linear Heat Detection (LHD) is a cable Firesense cable and its associated controllers allow
based system that provides economical temperature integration with many fire alarm and extinguishing
monitoring at the precise point of risk. The system is control systems, offering a complete system solution.
reliable, flexible and has the ability to detect abnormal In addition, the use of ATEX approved junction boxes
temperature variances before they develop into a and Intrinsically Safe barriers enable Firesense systems
fire situation. The comprehensive Firesense portfolio to be used in hazardous areas.
comprises both Analogue and Digital systems,
allowing a large range of both commercial and Firesense is the answer where conventional heat
industrial overheat and fire risks to be protected. detection is difficult to install and maintain.
ANALOGUE
ZONE
To Fire Alarm
Control Panel
Junction Box End Of Line Resistor
DIGITAL
METRES
To Fire Alarm
Control Panel
Junction Box End Of Line Resistor
Analogue (Resettable) Digital (Non-Resettable)
Analogue cable monitors the rise in temperature. Digital cable monitors when a specified temperature
An electronic controller continually measures the is reached. At this point, the construction of the
electrical resistance in the cable between the cable provides an electrical closed contact. This
metallic core and the outer braiding. If the change is is monitored by an electronic controller which can
sufficient the controller triggers an alarm for the hot identify the hot spot within metres. Digital cable is
spot zone. Analogue linear heat detector cable will non-resettable.
reset itself after an alarm once it has cooled.
PATOL Digital Cable
PATOL LHD Cable
PATOL Analogue Cable
Firesense LHD analogue cable and interfaces
A fully resettable, variable temperature heat detection system
Firesense Analogue Linear Heat Detection Cable Analogue cable is employed in conjunction with an end
(LHDC) is designed to provide early detection of fire of line terminating device and a zone monitoring unit
and overheating in circumstances where other forms or control panel with an appropriate LHDC interface
of detection would not be viable, either due to inability channel.
to sustain the environment requirements or through
prohibitive costs. LHDC may be installed in Hazardous areas by means
of Intrinsically Safe Zener Barriers. Similarly when
Extensive single zonal lengths of the LHDC may be the protected area is remote from the monitoring
installed with the ability to trigger alarms for hot spots equipment interposing cables may be employed.
occurring on very small sections of the overall cable.
LHDC analogue is a coaxial cable constructed with
a copper coated steel central conductor, an inner
insulation (dielectric), a tinned copper braid layer and
an overall protective sheath.
The primary mechanism of heat detection is the
resistance of the dielectric, monitored between the
central conductor and braid layer, having a negative
temperature coefficient.
PATOL LHD Cable
PATOL Analogue Cable
EU-R 19” Rack System
Analogue Cable Interface
The EU-R system uses Patol’s LDM-519-RMA-N
and LDM-519-RCS-N cards in conjunction with
our Master Motherboards allowing installation in
19” Rack mounting panels. The LDM-519-RMA-N
cards are designed to monitor a zonal length of
Analogue LHDC for elevated temperature states.
Two adjustable levels of alarm are provided, one of
which may be optionally employed as a Pre-Alarm.
The LDM-519-RCS-N card is a common interface
module allowing group monitoring of multiple zones.
LDM-519-LP
Analogue Cable Interface
The LDM-519-LP is designed to monitor a zonal
length of analogue cable for an elevated temperature
condition. It operates in conjunction with a single
core coaxial cable and an end of line terminator.
The module provides early warning of hot spots and
fire conditions on short sections of the overall zone
length, and is SIL 2 approved. Maximum zone length
for analogue LHDC is 500m when connected to this
module, subject to the maximum ambient temperature
and the configuration of the unit. It is designed so that
it can be configured to operate in two wire mode that
emulates the operation of conventional fire detectors,
allowing for direct interfacing with fire control panel
trigger circuits. The modular form of the unit enables
it to be provided in a variety of discrete housings and
readily integrated into special control panels.
Firesense LHD digital cable and interfaces
A fixed temperature system with accurate heat point detection
Firesense Digital Linear Heat Detection Cable (LHDC)
is designed to provide early detection of fire conditions The primary mechanism of LHDC is that the inner
and overheating in circumstances where other forms of cores insulating polymers are specially formulated
detection would not be viable, either due to an inability such that the polymers will plasticises at a specific
to sustain the environment requirements or through temperature, causing the inner cores to make contact
prohibitive costs. and send a signal to the controller.
Extensive single zonal lengths of the Digital LHDC may Firesense Digital LHDC is available with temperature
be installed with the ability to trigger alarms for hot ratings of:
spots occurring on very small sections of the overall
cable, with the ability to identify the distance to the 70°C
alarm point in metres. 90°C
105°C
The LHDC may be employed in a wide variety of 180°C
applications but is particularly suited where there is 240°C
harsh environmental condition, a physical or hazardous
in both braided and non-braided versions.
maintenance access constraint to protect the area,
or a requirement to cost effectively install detection in
close proximity to the risk.
PATOL Digital Cable
LDM-519-DDL/DDLX
Digital Interface with
Distance Display
These modules are designed to monitor a length of
Digital LHDC for a fire condition and may be configured
to operate in a two wire mode to emulate the operation
of conventional fire detectors. The units may be directly
interfaced with fire control panel trigger circuits or
addressable interfaces, and are SIL 2 approved. The
DDL has a 3½ digit LCD which activates on fire condition
and displays the distance into the zone the alarm has
occurred. Digital LHDC may be employed in lengths up to
2km with the DDL and up to 10km with the DDLX. Both
provide a 4-20 mA output proportional to the distance.
LDM-519-DIM
Digital Interface Monitor
The LDM-519-DIM module is designed to monitor a
length of Digital LHDC for both a fire condition, and
fault status (open circuit). The DIM module is certified
to be fully compatible with SIL 2 systems. Signalling of
fire and fault status is generated by means of volt free
contacts.
The module has been specifically designed in a DIN
rail format to allow it to be used in a variety of discrete
housings or integrated multi zone control panels.
Patol offer a complete range of special build panels
which can incorporate this module for projects that
require unique and tailored solutions.
Firesense LHD applications
Cable trays and racks Car parks
Generally cable trays and racks are located in Combustible materials used in passenger vehicles can
restricted spaces such as service tunnels and vertical result in fires that burn more intensely and generate
risers, making access difficult and potentially leading to higher temperatures than ever before with significant
undetected fire spread. Firesense LHD is ideally suited opportunity for fire spread. Detection systems in car
to this type of application as it can be installed very parks are often subject to the elements and vandalism.
close to the point of risk giving the earliest possible Firesense LHDC is ideal for this type of application
detection of an overheat condition. Firesense LHDC is where wind, dust and moisture are present which can
unaffected by the environmental conditions which may often lead to false alarms with other systems. It is also
cause false alarms with other detection types such as unaffected by seasonal weather temperature variations
dust and humidity. and provides a discrete form of detection.
Conveyors Trains and buses
Conveyor fires are most commonly caused by Fast moving trains present a particularly difficult fire
friction, which if allowed to spread can cause severe prevention situation as wind flow will quickly generate
damage to the belt, material being transported and an overheat condition into a full blown fire which can
the conveyor housing. Firesense LHD can be used spread rapidly. Buses can face similar risks, particularly
to provide point of risk detection to give an early with modern engines running at high temperatures.
warning of an overheat condition. Interfacing with other Firesense LHD is a solution aimed at combatting the
control equipment can initiate conveyor shut downs risk early enough for the fire to be extinguished without
and operation of suppression systems to prevent the damage or risk to life. Firesense LHDC’s ability to be
spread of a fire. Firesense LHDC is particularly suitable installed in tight spaces is a major factor in its suitability
as it can be installed where high levels of dirt, dust, for trains and buses.
wind and moisture exist and still be effective.
Warehouses Tunnels
Fires in densely packed racking can be detected with Tunnels offer limited access/egress points, making it
a localised Firesense LHD system. The cable can crucial that fires are detected at the earliest opportunity
be installed within the racking to provide detection to enable evacuation and fire extinguishing. Vehicle
very close to the point of risk, providing a discrete or fuel fires can be detected with Firesense LHDC
detection system which is unaffected by the normal installed directly over roadways and around sumps
working environment which may comprise dust and drains designed to contain fuel or oil spills.
and dirt. With Firesense LHDC, the warehouse and Firesense detection zones are calculated according to
racking can be split in to zones to reduce the search the length of tunnel, and can be linked to water, gas or
area and to activate the relevant sprinkler/suppression foam suppression systems for localised fire fighting or
system to restrict the spread of fire. activation of extraction systems.
Fixed and floating roof tanks Power generation
Tank farms containing highly flammable material in Power generation plants of all technologies employ
close proximity to each other pose a significant fire large equipment including turbines, motors and
risk. With floating roof tanks, the main risk of fire is actuators which can often be difficult to monitor for
from the ignition of vapour escaping from a damaged/ potential fire risk due to restricted access. Firesense
worn rim seal. It is essential that fires are detected LHD answers these problems with a cable-based
at the earliest opportunity to prevent widespread system that can be fitted in restricted spaces and
fire and activate suitable fire suppression systems. additionally is immune to the vagaries of dirt, dust
Firesense LHD can monitor vents, flanges, gauging and moisture which can upset other detection
points, manholes and general bund areas for fire. The technologies. Cable runs split into zones provide swift
system can be linked into a main fire system to trigger alarm response for evacuation procedures and fire
activation of deluge water spray/foam systems. suppression systems to be activated.
Floating Roof Tank Automatic Cable Reeler
Firesense LHD cable can be installed at the edge of the rim seal of a floating roof tank using
an automatic cable reeler to accommodate the rise and fall while providing the electrical
connection between cable and control panel. The mechanism is enclosed within a stainless
steel cabinet and the connecting cable is resistant to chemicals and high temperatures.
Firesense LHD fixings and ancillaries
Fixings
Genuine accessories can provide a greater guarantee industry requirements and are available in either mild
to the overall performance of Firesense Linear Heat steel or stainless steel versions. The mild steel clips are
Detection systems. This is particularly so in harsh and suitable for general indoor and outdoor use whereas
hazardous environments where Firesense stainless the stainless steel clips are suitable in environments
steel clips can be employed. Firesense clips have where the clip may be exposed to harsh environments
been specifically developed to comply with the latest and chemicals.
Firesense LHD – stacked and ready to go
Ancillaries
The Patol End Of Line (EOL) junction boxes are A variety of clips, coatings, cable ties, EOLs and
designed to terminate either analogue or digital LHDC. junction boxes ensure Firesense systems best meet
The EOL unit provides fault monitoring on the cable. end user specifications with a complete end-to-end
Analogue EOL units can monitor for both open and LHD solution. All Firesense systems and accessories
closed circuit faults. Digital EOLs monitor for open are accompanied by detailed installation guides and
circuit faults. technical documentation to ease installation and
maintenance.
Patol’s range of accessories has been designed
so that Firesense LHD systems can be configured
to perform flawlessly in many different situations.
Patol Ltd
Archway House
Bath Road
Padworth
Reading
RG7 5HR
United Kingdom
UK: +44 (0)118 970 1701
India: +91 90 00 963339
info@patol.uk.com
www.patol.co.uk
