EMC implementation - Busway
Busway reduce the risk of exposure to electromagnetic fields.
According to the WHO (World Health Organisation), exposure to electromagnetic fields can be a health hazard starting at levels as low as 0.2 micro-Teslas and could represent a long-term risk of cancer. Some countries have created standards that stipulate limits (e.g. 0.2 µT at 1 metre in Sweden).
All electrical conductors generate magnetic fields proportional to the distance between them. The design of busbar trunking with tightly spaced conductors in a metal enclosure helps to considerably reduce radiated electromagnetic fields.
The electromagnetic field characteristics of busbar trunking are welldefined and measurements show that they are far below potentially dangerous levels (see Fig. R14b).
In specific cases where particularly low values are required (computer rooms, hospitals, some offices), it is important to keep in mind the following: the induction generated around 3-phase distribution.
This is proportional to the current and the distance between the conductors, and inversely proportional to the square of the distance with respect to the busbar trunking and the screening effect of the case, the induction generated around busbar trunking.
This is less than the induction generated around an equivalent cable distribution, busway steel casing.
This attenuates the induction more than an equivalent aluminium casing of the same thickness (screening effect),the induction generated around busbar trunking with sandwiched bars.
This is particularly low because of the short distance between the bars and the additional attenuation provided by the steel casing.
Fig. R14a: xxx
Fig. R14b: Canalis busbar trunking system data
