cctalk Digest, Vol 88, Issue 2
Chuck Guzis
cclist at sydex.com
Tue Jan 4 14:28:55 CST 2022
On 1/4/22 12:15 PM, Jonathan Chapman via cctalk wrote:
> One of the top Google results:
>
> https://www.engineeringradio.us/blog/2012/02/the-open-delta-three-phase-service/
>
> Really really, there's only two pigs on the pole. And yet, delta power, though at a lower rating than transformer nameplate (vs. if you had three).
As I understand it:
High-leg delta is independent of open- or closed-delta.
Open delta uses two single-phase transformers primaries connected to
phases AB and BC. Secondaries are series-connected and 3-phase output
is taken from the high end of either secondary and the common connection.
Mostly a cost-savings measure as the efficiency isn't very good.
On high-leg, one of the secondaries is center-tapped and split
single-phase is fed from the center tap and either end of the secondary.
Said configuration can be a 3-winding full delta configuration or the
open-delta as detailed above.
--Chuck
More information about the cctech
mailing list