On Sun, 1 Mar 2020 12:10:41 -0800 (PST), Cynic wrote:

It matters quite a bit if you close an interconnector without the two sections being synchronised.

All interconnectors with the exception of the one from Lancashire to the Isle of
Man are DC and as such there is no concept of synchronisation.

Coupling sections of busbar or overheads is also in the main performed with both
ends in synchronisation because the system is always operated as one frequency
zone.


If a system split happens or there is a phase shift due to reactive components
then the breaker is closed under an automated procedure but only when the rate
and magnitude of the vectors are within preset parameters.
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