Ground Current Return Through Neutral

[Elmir]

I am working on ground grid installations connected to a power utilities 12.47kV 250MVA multi-grounded-neutral distribution system.

The utilities practice is to use single conductor 15kV concentric neutral conductors for distribution.

The phase fault current out of the substation is limited to 7kA by reactors on each of the outgoing feeders.

Can you comment your practices on a percent value to use for current split factors for primary faults to ground at the customers equipment? The equipment is all enclosed in a steel offshore shipping container.

I have read in grounding papers that majority of the fault current returns through the utility neutral.

Thanks

 

[alehman]

It's hard to say. Also see thread238-256567


Alan
“The engineer's first problem in any design situation is to discover what the problem really is.” Unk.