by LGM Products
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Key Highlights

  • Signaline Linear Heat Detection is a cost-effective method for fire safety in photovoltaic (PV) systems.
  • It can detect rapid changes in temperature along its entire length, providing early warning of over heating PV panels and fire hazards.
  • The technology offers benefits such as easy installation, low maintenance, and resistance to environmental factors.
  • Implementing Signaline Linear Heat Detection in PV installations can help ensure compliance with fire safety standards and prevent potential fire risks and is now recommended by leading building insurance firms, Zurich and Factory Mutual.
  • Case studies have shown the success of linear heat detection in commercial PV systems.

Photovoltaic (PV) systems, also known as solar PV panels, have gained popularity as a renewable energy source. These systems convert sunlight into electricity using semiconductor materials. While PV systems offer numerous benefits, it is crucial to consider fire safety measures to prevent potential hazards.

There is a need to rethink PV systems as generators. Building standards make allowance for fire detection and safety if your building incorporates a gas or diesel generator. Therefore, we need to consider the same risk for PV systems as these too are large generators of power.

And given that 97% of solar installations have been found to have significant fire risks, what if your biggest fire risk was not in your building but on your building?

Signaline Linear Heat Detection is a specialized technology that plays a vital role in PV fire safety.

It is designed to detect and provide early warning of fire hazards in PV installations. Unlike conventional fire alarm systems, which rely on spot detectors, linear heat detection can sense temperature changes along its entire length.

This blog aims to simplify PV fire safety by providing an overview of linear heat detection and its implementation in PV systems. We will explore the common causes of PV system fires, the role of environmental factors, and the benefits of using linear heat detection technology.

Additionally, we will delve into the planning, design, and installation considerations for implementing linear heat detection in PV installations. Compliance and standards for PV fire safety will also be discussed, along with case studies highlighting the success of linear heat detection in preventing PV system fires.

By understanding the importance of linear heat detection and its application in PV systems, we can enhance fire safety measures and ensure the reliable and efficient operation of solar PV panels.

Understanding PV Fire Risks

PV panels and associated electrical equipment pose specific fire risks that need to be addressed for proper fire safety in PV installations. PV systems generate electrical power from sunlight through the use of solar panels, which produce direct current (DC) electricity.

This DC power needs to be converted to alternating current (AC) for use in buildings or the grid.

However, the conversion process and the presence of electrical components increase the risk of fire. Faulty wiring, overheating inverters, and inadequate surge protection can lead to electrical malfunctions and potential fire hazards.

The Clean Energy Association, while conducting extensive research, discovered that 97% of audited PV systems had major fire concerns.

It is essential to implement suitable fire safety measures to mitigate these risks and protect both the PV system and the surrounding environment.

The Role of Environmental Factors in PV Fire Safety

Environmental factors play a significant role in PV fire safety.

Direct sunlight, which is necessary for solar energy production, can also contribute to the risk of fires in PV systems. The heat generated by the sunlight can increase the temperature of electrical components, potentially leading to malfunctions and fires.

Other environmental factors, such as the presence of flammable materials or the accumulation of dust and debris on the panels, can further enhance the fire risk. It is essential to consider these environmental factors when designing and implementing fire safety measures in PV installations.

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Footage of large scale solar array on fire at Lidl distribution centre in Peterborough, UK (Fire took place Feb 2024 –

Signaline Linear heat detection, with its ability to detect heat along the entire length of a cable, is a reliable solution for mitigating the impact of these environmental factors on PV fire safety.

Introduction to Linear Heat Detection in PV Systems

Signaline Linear heat detection is a specialized technology used to detect heat or sudden increases in temperature along a cable’s entire length. In the context of PV systems, linear heat detection plays a crucial role in detecting and preventing fires.

Unlike conventional fire alarm systems, which rely on individual spot detectors, linear heat detection provides continuous monitoring and early warning capabilities. This technology operates based on a fixed temperature threshold, triggering an alarm when the specified temperature is reached.

By promptly detecting and alerting to potential fire hazards, linear heat detection ensures prompt response and minimizes the risk of damage in PV systems.

How Linear Heat Detection Works

FT-EN range of EN54 approved linear heat detectors

Linear heat detection works by utilizing a specialized cable that is sensitive to changes in temperature. When the temperature in the vicinity of the cable exceeds a specified threshold, the cable undergoes a change in its electrical characteristics. This change triggers an alarm signal, indicating the presence of a potential fire.

The alarm signal is typically connected to a fire control panel or other monitoring systems, enabling prompt response and necessary actions. By continuously monitoring the temperature along its entire length, linear heat detection offers reliable and early detection of potential fire hazards in PV systems.

Benefits of Using Linear Heat Detection for PV Systems

Using linear heat detection in PV systems offers several advantages in terms of fire safety and overall system reliability. Some of the key benefits include:

Early detection: Linear heat detection provides continuous monitoring and early detection of potential fire hazards, enabling swift response and minimizing the risk of damage.

Reliability: Linear heat detection cables are highly reliable and can withstand harsh environmental conditions, ensuring long-term performance and minimal false alarms.

Efficiency: By detecting heat along the entire length of the cable, linear heat detection minimizes the risk of undetected fires and allows for targeted fire suppression actions.

Environmental suitability: Signaline has often been used for environmentally harsh conditions. PV systems need to withstand continuous UV, seasonal temperature variations and possible debris damage. Signaline is highly resilient to all these factors.

Planning and Design Considerations

Signaline FT-105-R was used to protect large solar array in Turkey

When planning and designing a linear heat detection system for PV installations, several considerations need to be taken into account. These include:

Selecting suitable cable type: Choosing the appropriate linear heat detection cable based on the installation environment and the specific requirements of the PV system. Our recommendation is that the cable installed should have an alarm temperature 20°C above maximum ambient temperature.

Ensuring proper cable routing: Properly routing the linear heat detection cable to cover the targeted areas, ensuring comprehensive coverage and effective detection. It is recommended to run a line of Signaline Linear heat detection across the back of every run of panels.

Integration with fire alarm systems: Coordinating the linear heat detection system with the overall fire alarm system to enable centralized monitoring, alerts, and response capabilities. Thankfully Signaline is compatible with all types of commercial fire detection systems and can conform to UL, FM and EN standards.

Compliance and Standards for PV Fire Safety

At time of writing, the UK, EU or US are yet to establish governing regulations for fire detection specifically within PV Systems.

However, leading global insurance firms have been conducting their own research and have concluded that Linear Heat Detection is a highly suitable technology to detect over heating PV systems.

In 2023 FM Global released their ‘Property Loss Prevention Data Sheet’ for roof-mounted solar photovoltaic panels. Herein, the use of Linear Heat Detection was called upon;

‘. . . installations where combustible construction is unavoidable, consider the installation of FM Approved, linear heat detection on top of the roof cover and below the PV modules. One line of heat detection can be placed within each sun-facing or east-west facing row of PV panels’

Similarly, this year Zurich Insurance Group, released their own study into the risk and mitigation thereof within PV Systems.

As with FM their research clearly pointed towards Linear Heat Detection as one of the view suitable technologies to provide efficient fire and cost-effective fire detection for roof top PV Systems.

These independent results point clearly towards Linear Heat Detection to be the correct choice for increased fire safety standards within roof mounted PV systems.


Signaline Linear heat detection is a crucial component in enhancing PV fire safety. By understanding the risks associated with PV systems, implementing linear heat detection technology, and adhering to compliance standards, you can significantly reduce the chances of fire incidents.

With proper planning, design, and installation practices, linear heat detection offers a reliable solution for early fire detection in PV installations. These technologies play a vital role in safeguarding PV systems, contributing to overall fire prevention success.

Frequently Asked Questions

What Makes Linear Heat Detection Ideal for PV Systems?

Linear heat detection is ideal for PV systems due to its reliability and efficiency in detecting potential fire hazards. By continuously monitoring the temperature along the entire length of the cable, linear heat detection provides early warning capabilities and ensures prompt response, minimizing the risk of damage or loss.

How Often Should Linear Heat Detection Systems Be Tested?

The frequency of testing linear heat detection systems depends on various factors, including industry standards and specific safety requirements. It is recommended to follow manufacturer guidelines and comply with relevant safety regulations to ensure the proper functioning and reliability of the system. Regular testing and maintenance help ensure the continuous effectiveness of linear heat detection in PV systems.

Signaline is delighted to announce the new 2024 product brochure!

What’s new?

Well we have been keeping busy here at Signaline HQ over the last 12 months and delighted to include some new and exciting products into the 2024 product brochure.

These include –

Signaline FT-68-EN

Launched in October 2023, the Signaline FT-68-EN is our lowest alarm temperature EN approved cable.

Approved by UL EU to EN54 part 28 and designed to work with the LocatorPlus-EN and FT-EOL-EN, the Signaline FT-68-EN Linear Heat Detection cable is great addition to our range.

Ensuring the fastest reaction to low temperature fires and over heating equipment, Signaline FT-68-EN also is a flame retardant, LSZH cable – setting it apart from the many other linear heat detectors on the market.

Signaline Q Clip

Always searching for ways to improve our customers experience the Q clip has been designed with the installer in mind.

The single piece stainless steel clip with EPDM liner does away with the need for cable ties and therefore massively reduces installation time and plastic waste.

Stainless Steel

Signaline Linear Heat Detection is a perfect solution for environmentally harsh areas. But what if there is also a mechanical risk?

Signaline Linear Heat Detection is now available with stainless steel braiding. Ensuring the highest protection for the cable while be used in mechanically dangerous situations.

Stainless steel coated FT-EN products are also now approved to EN54 part 28!

To check out these products and much more, please download your copy now!

To request a hard copy please email now and we will get one to you straight away!

For EN54 part 22 and part 28 installations to be installed correctly the Linear Heat Detection should be off set from the ceiling by 20mm.

The brand new Q Clip ensures this 20mm gap by its unique design. Utilising an elongated foot with a precise bend, the clip is secured with the 20mm off set.

This single piece clip removes the need for cable ties, reducing waste and significantly decreasing installation time on site.

The Q Clip uses a stainless steel 316L body with a EPDM liner. This provides excellent chemical and atmospheric resistance while ensuring that the cable is correctly cushioned witin the liner.

The clip is then secured to the ceiling through the M6 hole using a fixing bolt or screw.

The Q Clip is desinged specifically to be used with our range of Signaline FT-EN Linear Heat Detectors, but is also compatible with all our FT and FT-R cable ranges.

The Q Clip is the simple solution to reduce time, reduce waste and keep your installation compliant!

To find out more about Signaline Q clip and get a quotation for your EN54 installation please email

For further technical information download the datasheet here

Signaline is delighted to annouce that the stainless steel range of Signaline FT-EN cables have been added to the EN54 approval.

The FT-EN range is the market leading Linear Heat Detection system approved to EN54 part 28. With three alarm temperatures, alarm locator and end of line termination box with test switches, the FT-EN has been the go to solution for applications such as car parks, solar panels, and warehousing since its launch in 2020.

FT-EN range of EN54 approved linear heat detectors

A key features of Signaline FT-EN is the approval for enviornmental group III (outdoor environments) meaning the heat detection cable has been tested and approved to be used in harsh outdoor conditions.

However, Signaline Linear Heat Detection is also ideal for overheat detection within machinery such as conveyors or escalators.

In these environments the cable could be subject to mechanical damage. Siganline offers further mechanical protection on its cables by offering an additional stainless steel braid.

The steel braid is extremely durable and have a very high impact resistance, ensuring the Linear Heat Detection is protected and remains operable throughout its working life.

By adding the stainless steel vareties to the EN54 approval we ensure to our customers not only the durability of the product but also the alarm sensitivity.

The cables work by continuously monitoring the cable for any changes in temperature. When the alarm temperature is reached, it triggers an alarm condition. The LocatorPlus-EN controller then receives the signal and activates the appropriate response, ensuring early detection and swift response to fire incidents.

Signaline FT-EN with stainless steel is available in choice of 68, 78 or 88°C alarm temperature.

To download the approval please click here

To find out more about Signaline Stainless Steel please contact our sales team on or review the Signaline FT-EN range here

written by Nic Mogford-Revess on 01/Feb/2024

We are super excited to add Signaline FT-68-EN to our range of EN54 part 28 approved Linear Heat Detectors!

Adding to the market leading range, Signaline FT-68-EN adds further alarm temperature choice to our EN54 approved range with a low alarm temperature of 68°C. Allowing the customers now the choice of 68, 78 or 88°C alarms from this range. (for higher temperatures please see Signaline FT)

The new Signaline FT-68-EN is a linear heat detection system that provides unparalleled protection and reliability for your premises.

In this post, we will provide an in-depth analysis of this new technology and highlight its key features and specifications. We will also explore how it improves fire safety and discuss the advanced technology that powers it.

Additionally, we will delve into the practical applications of Signaline FT-68-EN and explain why it is an ideal choice for your safety needs.

So join us as we take a closer look at this exciting new product from Signaline and discover how it can enhance your fire safety measures.

Introduction to The New Signaline FT-68-EN Linear Heat Detection cable

The new Signaline FT-68-EN is an advanced linear heat detection cable that offers reliable and low cost fire detection along the entire length of the sensor cable.

Designed to operate with the LocatorPlus-EN and FT-EOL-EN it ensures precise and accurate alarm location. With EN54 part 28 certification, it guarantees quality and reliability.

Features and Specifications of Signaline FT-68-EN Linear Heat Detector

The Signaline FT-68-EN system offers early detection of fire by sensing excessive temperatures. It is suitable for use in car parks, cable trays, tunnels, and other electrical equipment.

signaline ft-68-en is ideal heat detection with car parks
Signaline FT-68-EN is ideal heat detector within a car park

The installation instructions are simple and easy to follow.

How Does Signaline FT-68-EN Linear Heat Detector Improve Fire Safety?

Signaline FT-68-EN enhances fire safety by swiftly detecting fires at their source and facilitating prompt response and containment.

It can identify hot spots, triggering alarms before the fire spreads. The cost-effective LocatorPlus-EN controller minimizes false alarms.

With continuous monitoring of over heating along its entire length, Signaline FT-68-EN ensures constant vigilance against early sign of fire.

The Technology Behind Signaline FT-68-EN Linear Heat Detector

The Signaline FT-68-EN utilises steel conductors, wrapped in a heat sensitive polymer to detect temperature changes along the entire cable. With a fixed alarm temperatures costly false alarms are reduced.

Signaline FT-68-EN also uses an enhanced outter coating which is LSZH and UV and corrosive resistant. Ensuring local compliance and long product live time.

How does the Signaline FT-68-EN Linear Heat Detector work?

The Signaline FT-68-EN works by continuously monitoring the cable for any changes in temperature. When the alarm temperature is reached, it triggers an alarm condition. The LocatorPlus-EN controller then receives the signal and activates the appropriate response, ensuring early detection and swift response to fire incidents.

The Signaline FT-EN Linear Heat Detection range

The FT-EN range of Signaline offers reliable and effective linear heat detection solutions. It includes various types of linear heat detectors suitable for different applications.

The range provides flexibility in terms of installation and customisation.

FT-EN range of EN54 approved linear heat detectors

Signaline FT-EN is compatible with different types of control panels and fire alarm systems.

Signaline FT-EN is approved to EN54 part 28, ensuring its compliance with European standards for fire safety. For global markets, Signaline also offers the Signaline FT range, which is approved to UL and FM standards.

Practical Applications of Signaline FT-68-EN Linear Heat Detector

Signaline FT-68-EN, a digital linear heat detection cable, is widely used in industrial and commercial facilities to detect fires.

Its practical applications include car parks, cable trays, service tunnels, manufacturing plants, and other areas where the risk of an alarm event is high.


The new Signaline FT-68-EN is a fantastic addition to the FT-EN family. With its low alarm temperature advanced features and specifications, it offers the perfect solution for many fire detection applications.

Whether it’s for industrial or commercial applications, the Signaline FT-68-EN is the ultimate choice for your safety needs.

Don’t compromise on fire safety. Invest in the best with Signaline FT-68-EN and ensure the utmost protection for your property and personnel.

Contact us today to learn more about this cutting-edge technology and how it can benefit you.

Signaline Linear Heat Detection will once again be on display at Secutech Vietnam 2023 in Hanoi!

Mark your calendars for the leading fire and safety event in South East Asia taking place from 19 to 21 July 2023 at the Friendship Cultural Palace in Hanoi, Vietnam.

Secutech Vietnam is the largest professional fire and security show in Vietnam and is expected to host around 350 exhibitors occupying 450 booths. Anticipating a significant turnout, the event aims to attract approximately 12,000 visitors.

As one of the fastest-growing markets in Asia, Secutech Vietnam provides access to upcoming opportunities within Vietnam and the SE Asia area. The event serves as crucial business and technology platforms for fire and security professionals within the region.

Don’t miss this opportunity to engage with industry professionals and explore the latest offerings in the field.

Visit our stand A801 to discover the future of security solutions and experience the innovative Signaline Linear heat detection technology firsthand at Secutech Vietnam.

Join us at the show and revolutionize your approach to fire detection with Signaline Linear heat detection.

Check out last years highlights of Signaline at Secutech 2022 –

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SKM Signaline HD Linear Heat detection Controller The Signaline HD SKM-95 and SKM-03 controllers are used with our Signaline HD linear heat detection cable.

They provide early warning of an impending fire by detecting overheating in environments that are difficult to monitor.

Some examples of where Signaline is used can be found here.

Here are the top five things you might not know about our SKM Controllers:

1. IP65 rated

  • Providing a higher level of ingress protection ensures reduced maintenance while allowing the controller and sensor cable to be field-mounted in exposed areas.

2. Approved by VdS to EN54 part 5

  • LGM strives to only offer products that reach distinguished international standards – the SKM-03 and SKM-95 controllers and Signaline HD and HD-R are approved to EN54 part 5 by VdS.

3. Flexible and easy to install 

  • The back box can be mounted ‘up’ or ‘down’ and the internal PCB and the front plate can be rotated to match. Additionally, both the SKM-03 and SKM-95 are supplied with an EOL termination box. You’re all set for an easy and quick installation!

4. Low Current Consumption

  • Even in alarm state the unit has a low current consumption which means there is no need for extra battery back up on conventional or addressable systems.

5. Compatible with conventional and addressable detection systems

  • For conventional systems the SKM-03 is the ideal solution. Whereas if you are using an Apollo addressable XP95 or Discovery loop then the SKM-95 can sit directly on the loop without the need for extra monitor modules!

If you want to find out more please contact our sales team.

Hazardous area brochure full. Intrinsically safe and explosion proof products from LGM Products.LGM Products is pleased to announce that our new hazardous area product brochure for 2017 is now available for download.

Facility safety within hazardous areas is paramount and the new brochure contains a comprehensive range of explosion proof and intrinsically safe (I.S.) products which will help keep workers and equipment safe from industrial fires and accidents.

You’ll also find the latest products suitable for hazardous areas such as HDL probe heat detectors, the RFD IR3 flame detector and the GNEx range of sounders and beacons.

All the units listed in the brochure have at least one third party certification from a recognised international body as evidence of the quality of the products we can offer.

These approvals include ATEX, IECEX, INmetro, GOST-R, SIL and UL among others.

Download the new brochure now, browse our hazardous area webpages or contact our sales team for further information and quotations.

Email or call us on 01252 725257.

Signaline linear heat detection cableIn the last month, we were delighted to sell the millionth metre of our Signaline Linear Heat Detection cable.

If you stretched it out from our offices in Farnham, UK the linear heat detection cable we have distributed would reach all the way to Berlin in Germany!

We want to thank all our customers and distributors around the world who have specified, purchased and installed our detection cable.

Signaline Linear Heat Detection is designed for use with a wide range of commercial and industrial fire detection systems.

Our cables detect heat anywhere along their length and are compatible with both addressable and conventional alarm systems.

The million meters sold have been used in a variety of applications from car parks in the Brighton, UK to cement works in Vietnam.

For more information about our range please browse our website for more information or contact our sales team directly.

Syncroxt_large-314x400We are pleased to inform our customers that the new Syncro XT+ Extinguishant Control Panel is fully compatible with our Signaline Fixed Temperature range.

The Syncro XT+ is a multi-area addressable extinguishant panel complying with EN12094-1. The panel can be used for up to 16 zones over 1 or 2 loops making it suitable for small or large fire extinguishing systems.

Our Signaline Fixed Temperature (FT) linear heat detection cable can be linked to an addressable interface of the Syncro XT+ loop.

When Signaline FT detects a fire, the panel identifies the detector’s address locating the fire and releasing an extinguishing agent to the specific area.

Signaline FT is maintenance free, low cost and easy to install. Used in conjunction with the Syncro XT+, customers will benefit from a cost-effective fire detection solution which quickly detects and identifies the location of a fire.

Signaline also reduces instances of false alarms meaning the extinguishing agent is not released unnecessarily causing unwanted damage and costly repairs.

Among many applications, the Syncro XT+ and Signaline FT combination is suitable for use in computer server rooms, IT infrastructure, kitchens and factories.

The panel can also be used with Apollo or Hochiki addressable loops.

Both the Syncro XT+ and Signaline FT are available for purchase from LGM Products.

Please contact our sales team directly for more information:

Did you know that Signaline offers the only EN54 approved analogue linear heat detection system in the world which is loop powered and addressable?

Our Signaline SKM-95 Controller – approved by VdS – is compatible with Apollo XP95/Discovery addressable systems.

The controller has its own addressing dip switch and is powered directly from the loop. This eliminates the need for loop interfaces or additional power supplies and provides significant cost savings.

Using a Signaline SKM-95 Controller is an ideal way of integrating linear heat detection with large BMS fire systems, such as in a multi-storey car park installation.

Combining the SKM-95 Controller with Signaline HD analogue cable allows you to integrate this part of your fire detection system onto the same loop as other areas of your network. In short, it’s a very efficient and practical form of fire detection.

The SKM-95 Controller is also IP65 rated and comes with an End of Line Unit, making installation extremely simple and efficient.

If you would like to make an enquiry about this product please email:

Signaline COLD Gas Leak Detection SystemUsing unique patented technology, our award winning Signaline COLD Liquid Gas Leak Detection System is specifically designed to provide a highly sensitive and reliable solution for monitoring sudden leakage of liquefied (cryogenic) gas.

All the information for this innovative gas detection solution is now available on the Signaline website.

Our dedicated section for Signaline COLD includes background information on gas leak detection, our full product range and relevant technical datasheets.

The detection system has a wide variety of applications, but is particularly suited to the liquefied natural gas industry including LNG storage vessels, equipment and pipelines.

For more information or a quotation please contact our sales team on +44(0)1252 725 257 or email

P Clip MetalAt Signaline, we are always striving to advance the standards of our products and we are pleased to announce improvements to our range of ‘P’ Clips.

Our high quality fixation clips ensure that Signaline detection systems do not cause false alarms and have excellent system integrity. They are also designed to reduce the time and cost of installation.

Our standard metal P Clip is now manufactured in stainless steel which means the clip is resistant to corrosion in salt-laden environments and areas where chemicals are present.

The stainless steel P Clip still benefits from a UV and ozone resistant cushion insulator.

We have also managed to maintain our existing pricing on these new P Clips allowing us to deliver an improved product for the same price.

Unless otherwise stated, all orders will now be fulfilled with the stainless steel clip.

New Plastic P Clip

P ClipIf metal is not suitable for your application due to heat transfer concerns or is proving unnecessarily costly, we can now offer our customers a new plastic (nylon) P Clip.

The plastic P Clip still has good overall resistance to chemical corrosion and UV rays and can also be used with our water detection cable.

Please click here to view our P Clip datasheet or contact our sales team:

Signaline Linear Heat Detection CableOur Signaline Fixed Temperature linear heat detection cable was recently chosen to protect a conveyor belt system for a cement works in Vietnam.

Cong Thanh Group selected Signaline FT 68 as it offers a low cost fire detection solution for industrial and manufacturing settings.

The linear heat detection cable provides early detection of overheating on the conveyor belt and can be easily removed, replaced or re-positioned during maintenance work.

The cable was integrated with third party fire equipment demonstrating that the Signaline range is a flexible and versatile option for installers.