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#17519 - 11/27/02 06:03 AM Delta Transformer Configurations
dturner Offline
Member

Registered: 02/20/01
Posts: 16
Loc: Harrisburg PA USA
I need a quick refresher. When hooking up transformers in a DELTA configuration what are the pro's and con's (other than cost) of using "Closed Delta" or "Open Delta".

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#17520 - 11/27/02 02:15 PM Re: Delta Transformer Configurations
electric-ed Offline
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Registered: 07/08/02
Posts: 184
Loc: Canada
If one transformer of a delta-delta connected bank becomes defective, it can be disconnected, and the system will continue to function as an open-delta, but can only deliver 58% of its closed-delta rating.

In my area they were used when transformer insulation wasn't as good as it is today.

They used to install two transformers, connected open-delta, and add the third, (in other words "close the delta") at some point in the future when the load increased.

Ed

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