Using Messenger Wire with Linear Heat Detection

3 mins read

Messenger wire is a secondary, steel wire used to add rigidity to cable. It does not carry any signal but is used to add strength to the cable to prevent sagging when running through the air or to make it easier to fish over long distances in commercial installations. In effect, messenger wire provides a backbone so that the cable carrying the signal is not under any strain.

The most common application of messenger wire that we come across is on telephone poles to carry telephone cable through the air with minimal sagging. However, it can be used to assist almost any kind of cable that requires extra support through the air, including linear heat detection cable.

Using Messenger Wire with Linear Heat Detection

Messenger wire can be combined with any FyreLine Linear heat detection cable to provide extra support where it is needed. Messenger wire is wrapped around the detector at approximately one turn per foot and provides a support wire, designed to simplify the installation of the LHD in areas where mounting is difficult due to the lack of appropriate support structures or mounting surfaces such as applications with high ceilings and large open areas.

FyreLine Linear Heat Detection

The FyreLine linear heat detection system can detect heat anywhere along its length to provide fast and reliable heat detection with accurate location reporting for a variety of applications.

FyreLine is easy-to-install and maintain and is cost effective. FyreLine is available in two versions:

FyreLine Digital Linear Heat Detection

FyreLine Digital

FyreLine Digital is a fixed temperature linear heat detection system available with four different temperature ratings; 68°C, 88°C, 105°C or 185°C. Once FyreLine Digital heat sensing cable reaches its rated temperature, a signal is sent to the fire alarm control panel.

FyreLine Analogue Linear Heat Detection

FyreLine Analogue

FyreLine Analogue heat sensing cable continually monitors for increases in temperature and can, therefore, be configured to provide a pre-alarm as well as a full alarm condition. This provides the ability to investigate potential fires before action is taken. Once the cable reaches its predetermined temperature a signal is sent to the fire alarm control panel to raise the appropriate alert.

How to Install Messenger Wire and LHD Cable?

When using messenger wire with FyreLine linear heat detection cable, turnbuckles and eyebolts must be used each end of a straight to put the support wire under tension. The run between turnbuckles should not exceed 76m (250ft) and the cable should be supported at regular intervals with approved intermediate fasteners. The spacing of intermediate fasteners will largely be determined by the application but should never exceed 15m (50 feet).

When using messenger wire in outside applications, increased detector support must be provided by using additional intermediate fasteners with closer spacing.


For more information about the FyreLine Linear Heat Detection system, or to discuss any of the other products that Eurofyre have to offer, please feel free to get in touch either by phone on +44 (0) 1329 835 024, by email to [email protected] or via the online enquiry form situated on our contact page.

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