Busbar vs Cable

[HarryCadman]

Fire Prevention

Busbar Vs Cable

Cable presents several challenges to the installer. Among these is the need to terminate multiple cables in switchboards. With cable, entry holes must be drilled on-site, and particular care is needed to ensure accurate positioning of these holes and avoid the risk of swarf falling into the electrical connections, causing short circuits. Cable ladders would also need to be installed to support the cable during installation, as well as circuit protective conductors. These could require a dedicated team to set up. The cables would need to be tidied up, glanded into the switchboard and terminated. Each of these operations includes the risk of damage to the insulation, to the core itself, and bad termination that increases the risk of fire. In contrast, busway is much more straightforward. A single run of busway replaces several runs of cable, along Selecting conductors Correct conductor and overcurrent-protection sizing is critical in reducing electrical fire risks. Busways can help designers get around the electrical fire risks that conductors can pose. with associated cable trays. Busway also needs fewer fixings than the equivalent length of cable.

Busway temperature rises and short circuit withstand are known and independent of the installation, they are tested and certified according to IEC 61439-6 standards. In addition, coordination of the Schneider Electric circuit breaker and busways ensure an optimized sizing with perfect protection against short circuit conditions. Also, for high current circuits, multiple cables in parallel can lead to uneven distribution of currents and the risk of abnormal temperature rises. Installation standard IEC 60364- 5-52 Clause 523.7 recommends busbar trunking systems (busways) above four parallel cables. In France, this is mandatory, according to UTE C 15-105 chapter B.6.2.

Another major advantage of busbar is the use of tap-off units instead of a derivation box. These incorporate protective devices, which allow the busbar to feed other sub-circuits in the building. A variety of protective devices are available, including modular circuit breakers and molded case circuit breakers.

The rated performances are standard-compliant, irrespective of implementation, and the tap-off units are seamless to install and deliver high contact quality during aging. Mechanical protection of conductors significantly reduces the risk of insulation faults due to external factors, such as rodents, moisture, and pollutants. IEC 60364-4-42 2010 422.3 mentioned earlier, states that busbar need not be protected by 300mA RCDs in locations with special risk of fire, as they are not considered likely to cause a fire from insulation faults.

Please come back to see additional webinars, leaflets and information to help you decide on our busbar system and the benefits it brings of using cable.