Delta C2000 Series User Manual page 674

TN-C system
TN-C: PE and N are two separate conductors in an electrical installation similar to a three-phase 5wire
system, but near the power side, PE and N are combined into a PEN conductor similar to a three-phase 4
wire system.
TN-C-S system
TN-C-S: A combined earth and neutral system (PEN conductor) is used in certain systems but eventually
split up into two separate conductors PE and N. A typical application of combined PEN conductor is from
the substation to the building but within the building PEN is separated into the PE and N conductors.
Direct connection of PE and N conductors to many earthing points at different locations in the field will
reduce the risk of broken neutrals. Therefore this application is also known as protective multiple earthing
(PME) in the UK or as multiple earthed neutral (MEN )in Australia
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