Substations

[RichB]

Morning all,

Here is the question and then I'll give the specifics,,,

I understand how the substation works regarding phase to phase and phase to ground faults, i.e., opens, waits recloses checks for fault reopens as needed for a set number of times then stays open if fault is not cleared.

Here's where I got stumped--I mean I just drew a blank (total Brain F*rt) and still have no idea how to answer this,,

We allow the POCO to run their 26Kv on our bridge structures--They run PVC underground then transition to RGS across the structure then back to PVC. The question that came up is as follows:
Since they do not pull in an EGC how is the RGS bonded so as to give a path for fault current or does our bridge structure just become energized in the event of a ground fault in the RGS, and since the conduit is in racks hanging under the structure can the fault current go to ground and show a ground fault at the substation?

In other words--short version--how does a ground fault get cleared in the above situation or does our structure just sit there hot and cooking?

Thanks all!!

 

[mgookin]

I suggest you call a POCO engineer. They're usually very accessible and helpful. Start with their construction division. Every POCO could be different; hence call the POCO whose system it is.