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#128220 - 10/17/02 09:52 PM Discussion- Residential Dist. Systems
Scott35 Offline

Broom Pusher and
Member

Registered: 10/19/00
Posts: 2724
Loc: Anaheim, CA. USA
This thread can be used to discuss the drawings posted in the Technical Reference area intitled:

Residential Distribution systems

Feel free to ask question(s), make comments or discuss this topic in detail.

If you would like these or other drawings from the Technical Reference area sent to you as Raster Images [.gif, .jpg, .bmp], as Metafiles [.wmf], or as AutoCAD R14 files [.dwg], contact me via e-mail or post a message in this thread.
Please specify which type of file format you would like, along with the name of drawing / text .
The images / text will be sent via ".ZIP" compressed file, using PKZIP 2.60 for Windows / DOS. If needed, I can send as Self Extracting Zip files, which work fine in Windows 95, 98, Me, NT4 and 2000 Enviroments, but have not worked correctly under Windows XP as of 08.01.2002.

Let me know if these drawings are helpful or if they suck!

Scott S.E.T.
_________________________
Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!

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#128221 - 10/18/02 07:05 AM Re: Discussion- Residential Dist. Systems
resqcapt19 Offline
Member

Registered: 11/10/00
Posts: 2209
Loc: IL
Scott,
On the first drawing where XO on the 7.2/12.4 kv distribution system is not used as a circuit conductor, shouldn't that system be labeled 3 phase, 3 wire?
Don
_________________________
Don(resqcapt19)

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#128222 - 10/18/02 02:05 PM Re: Discussion- Residential Dist. Systems
Scott35 Offline

Broom Pusher and
Member

Registered: 10/19/00
Posts: 2724
Loc: Anaheim, CA. USA
Don,
Are you referring to Fig. 1-1: Multigrounded Common Neutral Drawing?

If so, I'm not sure if the system would be best described as 3 wire or 4 wire.

The Common Star point for the Wye connected Secondary Coils (AKA "X0") is driven to ground and a Grounded Conductor is brought out from the Star point.

The Grounded Conductor is bonded to the Center Tapped Grounded Conductor used on the 120/240 VAC 1 phase 3 wire Secondaries.
Also, one end of the Primary Coil on the 1 phase Transformers is connected to the same Common Grounded Conductor.

Looking at the Medium Voltage Feeders leaving the Delta / Wye Transformer, the system looks like a 4 wire Wye.
Looking at the rest of the system, it seems to be 3 wire - except where the side of the Primary coils are terminating to the Common G.C., then it leans back towards 4 wire again.

I'm unsure if it would be best classified as 4 wire since the Grounded Common Conductor is also Common to the low Voltage Secondaries.

Anyone have an answer???

Thanks for bringing this up for discussion.

Scott S.E.T.
_________________________
Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!

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#128223 - 10/18/02 02:33 PM Re: Discussion- Residential Dist. Systems
Bjarney Offline
Moderator

Registered: 04/10/02
Posts: 2561
Loc: West-Southern Inner-Northeast ...
I can't be sure but I'll bet this will muddy the issue.
http://www.cooperpower.com/library/pdf/R201902.pdf

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