How to Select Flame Retardant Cables

Ⅰ. Flame retardant cables

Flame retardant cables refer to the cables that are burned under the specified test conditions, and after removing the source of fire, the flame spreads within a limited range, and the residual flame or residual burn can be extinguished by itself within a limited time. The fundamental feature is that it may be burned out in a fire and cannot be operated, but it can prevent the spread of the fire. Generally speaking, if a flame retardant cable catches a fire, it can limit the combustion to a local area so as to protect other equipment and avoid greater losses.

Ⅱ. The selection of flame retardant cables

1. Dense cables

The flame retardancy of cables when multiple cables are densely arranged should meet the requirements of the appropriate category in accordance with “the experiment method of bundled wire and cable burning ", the configuration of cable, the prevention of catastrophic accidents and the principles of economy and reasonableness.

(1) In the same channel, it is not advisable to arrange non-flammable cables and flammable cables in parallel.

(2) For the following places or circuits that need to be energized within a certain period of time due to external fire, the exposed cables should be fire-resistant or flame retardant cables. Important circuits such as fire protection, alarm, emergency lighting, interrupter operation DC power supply and emergency shutdown power supply of generator sets; Computer monitoring, dual relay protection, security power supply and other dual circuits share one of the circuits when the same channel is not isolated from each other;

2. The implement method of fire resistant protection of the exposed cable

When there are fewer cables, fire-resistant coatings and tapes can be applied or the cables can be put through fire-resistant pipes. When there are many cables in the same channel, they should be laid in the refractory trough box. In addition, the power cable should be ventilated. It can be semi-enclosed in an environment without flammable dust. When the section of cable protection on the bridge is not long, a fire-resistant package can also be used. In oil tank farms, important public buildings with wooden structures, high-temperature places and other situations with high requirements for fire resistance, installation and economic performance, non-combustible mineral insulated cables can be used. With the requirement of fire protection, self-contained oil-filled cables can be laid in sand in public corridors, passenger tunnels, bridges. Cable trenches close to oil-containing equipment such as high-voltage current and voltage transformers should be sealed with the trench cover in this section.

3. Dense places

In cable-intensive places or enclosed passages with high safety requirements, automatic fire detection and alarm devices should be equipped, which are suitable for reliable environmental actions. The oil supply system of the exposed oil-filled cable shall be equipped with an automatic fire alarm and locking device that can reflect the oil injection status. In places with high safety requirements, such as cable-intensive parts of underground public facilities and terminal installations of multiple oil-filled cables, special fire-fighting facilities such as water spray fire extinguishing can be installed.