ZENER 8000-V Installation Manual
IM00165
59
(b)
To take advantage of the limited fault current available in the event of an earth fault in an IT system
with impedance earthed neutral. This arrangement is widely used in the mining industry on the basis
that a substantial proportion of electrical faults, particularly associated with cables, which might begin
as earth faults and otherwise progress to a major high current faults with considerable potential for
personal injury and equipment damage.
A considerable amount of the literature on the topic of IT supply systems, including a number of International
Standards, is written around the first reason above and is a source of confusion if read with the second reason
in mind.
