On Mon, 2 Mar 2020 00:37:10 -0800 (PST), harry
wrote:

On Sunday, 1 March 2020 20:10:43 UTC, Cynic wrote:
It matters quite a bit if you close an interconnector without the two sections being synchronised.

All you need is three lamps.

Eg:-

https://www.nuclear-power.net/nuclea...oscope-method/

Lamps were last used in anger in the 1980's, where there was still some
generation connected at distribution voltages

Syncroscopes were always used for synchronisation at main generation sites. You
still had a single check light but the pointer showed the rate of slip relative
to the grid

But both methods are wholly reliant on the skill of the operator and the speed
of breaker closure, get it wrong and you can very easily wreck the generator
rotor.

Everything (as in post 1987 ish in the UK ) is now done electronically such that
it is impossible to synch incorrectly, even with a total system split and a
large disparity on phase rotation rates and voltages. You prime the breaker
with the appropriate sync mode and just wait, for up to 30 mins if necessary at
which point it will time out.

Generation just runs the governor against the reference voltage and frequency
and autocloses within preset voltage and slip parameters. The level of operator
skill required is near zero.







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