Power Infrastructure for the Data Center part 3

there are two location of distribution for power and network. the first is under raised floor and the other is overhead. also there are two types of distribution; the standard cabling and busbar trunking. but there is common rules in distribution like much cables under raised floor without management will hinder the air flow. also the network and power cables must be separated by a distance to avoid electromagnetic interference (EMF). so the best option is to put a power cable over head and the network cables under raised floor.
the standard cables is less flexible and has fixed power limit also it is inexpensive. the busbar trunk is flexible as you can get three or single phase using tap off and ever tap off has its breaker. and the power rating  is very high but it is very expensive.