Gapped core CTs
Gapped core CTs
(OP)
I see that there are manufactures that make gapped core Cts. Does anyone actually use these to help mitigate CT saturation during transformer inrush or other DC offset issues?
When was the last time you drove down the highway without seeing a commercial truck hauling goods?
Download nowINTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS Come Join Us!Are you an
Engineering professional? Join Eng-Tips Forums!
*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail. Posting GuidelinesJobs |
|
RE: Gapped core CTs
At the utility where I work, we commonly specify gapped core CTs for:
- 132 kV line differential protection schemes (40 kA, X/R can be over 30).
- 11 kV transformer differential protection (8 kA, X/R can be over 50).
With some negotiation, most major suppliers will source (or build) gapped CTs.
We've usually specified PX class to AS60044.1 with additional requirement of Kr < 10%.
I've never found inrush to be much of a problem for CT performance, because the
CTs on the high side of our transformers experience less demanding conditions.
Three phase bolted faults with a high X/R are a problem.
Thanks,
Submonkey