EuroWire May 2021

Technical Article

Construction of fire-resistant fibre-optic cable • Four coloured multi-mode optical fibres MM 50/125 OM2 placed in a loose tube • A loose tube of 2.5mm (±0.5) diameter, filled with thixotropic gel • The colours of the fibres in the tube: red, green, blue, yellow • Double fire barrier • Glass fibre reinforcement swelling under the influence of water • Cable outer sheath made of red UV-stabilised halogen-free plastic (HFFR)

extra high range (1,012 THz and above). This is an area of infrared- electromagnetic radiation from outside the visible light range. A fibre-optic cable is essentially dielectric, with no metal elements, so there is no concern that it will induce voltages that cause the flow of parasitic currents that may damage the elements that cover the fibre optics. In addition, the very low attenuation of signals transmitted via fibre-optic cable means that the distances between the devices of the system can be large – much larger in comparison with connections made with copper cables. New fibre-optic cables manufactured by Technokabel SA for fire protection systems To meet the emerging market demand, Technokabel SA was the first company in Poland to design and, after obtaining the necessary certifications and approvals, implement into production a new fire-resistant, fully dielectric fibre-optic cable dedicated to fire protection installations. The cable is 100 per cent resistant to interference, and therefore is suitable for laying in the immediate vicinity of power cables, which allows cable route designers to save space in tunnels. It has a small diameter and is flexible to ensure ease of installation and laying. Technoflame FOC-2-SLT-HFFR PH120/E30-E60 is a fire-resistant and waterproof fibre-optic cable with one central loose tube (with up to six fibres per tube), designed for use as part of the following installations: • Fire alarm systems • Smoke and fire control systems • Fixed fire-fighting equipment • Audible warning systems • Monitoring, cooperation and integration of fire protection systems The cable can be used in rooms protected by fixed water extinguishing devices (sprinklers), and can be laid with low-current and telecommunication cables. It is made of completely halogen- free materials, which means that it is suitable for use where high fire safety is required. The cable is flame retardant, its smoke emission in fire is low and the gases released are not toxic and do not cause corrosion. The waterproof fibreglass reinforcement used in the cable provides the necessary strength during installation, as well as protection against mechanical damage and rodent attacks during operation. A loose tube filledwith thixotropic gel prevents water fromentering the fibre-optic fibres and stops moisture penetration along the cable. The cable is versatile and can be used in indoor and outdoor installations and tunnels. ▲ Figure 2 : Technoflame FOC-2-SLT-HFFR PH120/E30-E60 fibre-optic cable The functionality of the fibre-optic cable and the application

Performance characteristics and parameters

Number of fibres

Tube diameter (mm)

Cable outer diameter (mm)

Cable weight (kg/km)

up to 6

2.5 ±0.5

7.8 ±0.5

80

Unit attenuation, maximum: for 850nm

≤ 2.3dB/km ≤ 0.5dB/km

for 1,300nm

Core diameter Jacket diameter

50μm

125μm 250μm

Primary coverage diameter Operating temperature range: during operation

from -30 to 70°C from -5 to +50°C

when installing

Minimum bending radius: static

10x cable diameter 15x cable diameter

dynamic

Maximum tensile strength: during operation

1,500 N 2,000 N

when installing

Crushing resistance: long term

2,000 N 5,000 N

short term

Corrosivity of gas separation

PN-EN 60754-1/-2 IEC 60754-1/-2 approximately 6.8

pH

Conductivity

approximately 0.4µS/mm

Smoke density

PN-EN 61034-2 IEC 61034-2

Light transmittance Flammability of cable

minimum 80 per cent

Does not spread the flame Flame retarded

Flammability tests

PN-EN 60332-1-2 IEC 60332-1-2

Function support according to EN 50582*: up to 60 min (E30-E60)

DIN 4102-12 CSN 73 0895 STN 92 0205 PN-EN 50200 + Annex E

P60-R PS 60 PH120

Execution according to

CNBOP-PIB-KOT-2020/0196- 3701 edition 1, WT-TK-51

Reaction to fire

Cca-s1a,d0,a1 (PN-EN 13501-6)

* The maximum change in fibre-optic attenuation according to EN 50582 is 2dB/m and depends on the cable installation method.

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May 2021