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Open versus Closed Transitioning on Medium Voltage Switches

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Redskinsdb21

Mining
May 4, 2009
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In my research on open versus closed transition switching, I fount this:

Open Transition Transfer Switches
An open transfer switch’s connection with a generator is established before the utility is shut off, and then the swap is made quickly once the connection has been safely established. Open transition switches are often regarded as the most cost-effective and widely used systems, as they’re compatible and viable for most business operations and needs.

Closed Transition Transfer Switches
A closed transition transfer switch performs a similar but slightly different function. With a closed system, the two power sources (utility and generator/backup) are allowed to briefly overlap, which limits or removes the momentary stutter in power that open systems can occasionally create.

My question is, with open do you momentarily loose power but with closed transitioning you do not due to the brief overlap?

Any other differences known?
 
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