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LibraLogic
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| Joined: | Wed May 14th, 2008 |
| Location: | West Palm Beach, FL, USA |
| Posts: | 136 |
| Exams Taken: | GS, ME, CD, BT | | Exams Passed: | GS, CD, BT | | Describes Me: | Determined |
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Posted: Mon Jun 16th, 2008 05:23 pm |
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Ok...heres the basic priciples Ive gathered re: Delta-Wye Connections, and Im looking for somebody to confirm these so I can commit to memory and move on...
If connecting 1-HOT(A) and 1-HOT(B) in DY=208v; in DD 240v.
[The result of 208v in the DY is due to the 3phs's. 3phs consists of 2 hot and 1 Ntrl. Since theres only 2 hot ((AT)120v ea) for a 3phs you use the sq-rt of 3= 1.73)....and in other words you take 1 hot ((AT)120v) x 1.73 which is how you can only extract 208v. from DY]
[The result of 240v in the DD is simply 2x each hot or (2 x 120v)=240v]
If connecting 1-HOT(A) and NEUTRAL(N) in DY=120v; in DD 208v-(pls verify).
Therefore in DY: available Volts are 208v(3phs), 208v (Sngl Phs), and 120v (Sngl Phs)....
Whereas in DD: available Volts are 240v (3phs), 240v (Sngl Phs), and 120v (sng Phs)
Please share your thoughts.
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Far Galaxy
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| Joined: | Tue Jun 19th, 2007 |
| Location: | Apprx 32.2degrees N Latitude |
| Posts: | 1252 |
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Posted: Tue Jun 17th, 2008 02:34 am |
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god bless........I skip on this topic too difficult for architects.
maybe I won't have it in my test, and if it will, 1 question, guess....
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beerae
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| Joined: | Fri Jan 25th, 2008 |
| Location: | Ohio USA |
| Posts: | 158 |
| Exams Taken: | PD, GS, LF, ME, BD/MM, CD, SP, BP, BT | | Exams Passed: | PD, GS, LF, ME, BD/MM, CD, SP, BP, BT | | Describes Me: | |
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Posted: Tue Jun 17th, 2008 12:37 pm |
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| I am a little foggy on this topic as well, but I believe that 3 phase connections (both delt a wye) have three hot wires, if you desire a neutral (most of the time with wye, but rarely with delta) that actually becomes your forth wire.
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LibraLogic
Member
| Joined: | Wed May 14th, 2008 |
| Location: | West Palm Beach, FL, USA |
| Posts: | 136 |
| Exams Taken: | GS, ME, CD, BT | | Exams Passed: | GS, CD, BT | | Describes Me: | Determined |
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Posted: Tue Jun 17th, 2008 12:42 pm |
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Ok, I could understand that logic, however would adding the fourth wire, (resulting in 3 hots) change any of the available voltage of the below...?
"Therefore in DY: available Volts are 208v(3phs), 208v (Sngl Phs), and 120v (Sngl Phs)....
Whereas in DD: available Volts are 240v (3phs), 240v (Sngl Phs), and 120v (sng Phs)"
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beerae
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| Joined: | Fri Jan 25th, 2008 |
| Location: | Ohio USA |
| Posts: | 158 |
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Posted: Tue Jun 17th, 2008 12:44 pm |
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| No, I think you have the voltages right...
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Current time is 09:46 pm | |
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