This is a hypothetical question and is based on thread238-246755. There it was established that the rating (amperage wise) of a transformer secondary was meant to be interpreted as being 600A in each phase or line.
Say for a moment, that this transformer was a delta-wye, 500 kVA, and is...
Here is a forthright link toward requesting WINDoc.
http://www.engineeringtalk.com/news/abc/abc119.html
It will be in the "NOTE" at the beginning of the article.
In selecting the proper size feeder to a transformer, should I consider the type of load the transformer feeds or should I just go by the primary current required? I am curious if one ever considers that the load may or may not be continuos or non-continous. I have a 3-Ph, 480V-208/277V, 45 kVA...
Got to following URL for an excellent description of a ground resistance tester and methods:
http://www.aemc.com/techinfo/
then click on Ground Resistance Tester
At our facility, rather than be confused from the “get-go”, we are encouraging the use of standard tables found in NFPA 70E, Tables 130.7(C)(9) and 130.7(C)(10). In those tables, many of the activities that an electrician will be involved with are listed along with the appropriate PPE that...
Thank you, jbartos-Response: Jan 31, 2004 marked ///\\1. Have you estimated kVA size of this transformer? What about a type, a pad mounted or mobile? ///Initially, I had envisioned a 3-phase, 1500 kVA, 13.8 kV – 480/277V dry type pad mounted-Y having 1804 amps on secondary. This would then feed...
The trailer complex is only going to be up for 6-9 months. Consequently, we are also looking at using heavy G-GC cords to supply the trailers. I am already supplying about four other trailers from a pole mounted 13.8-480V 3-phase Xfmr because these trailers do have 120/208V 3-phase service...
dpc you are correct in that I could use three 13.8kV-120/240V Xfmr's. I was thinking that I cold simplify the drops from the pole to just one set of conductors coming down the pole whereas with three single phase Xfmr's I would have three drops and three connections to the grid lines. I suppose...
I need to power 16 double-wide trailers, each at 120/240V and each double-wide having 2-100A single phase panels. I have a 13.8kV supply. I am thinking of a 3-phase 13.8kV-480/277V dry type Xfmr and then split up phases to feed three single phase 480-120/240V Xfmrs. However, I believe that if...
Thank you all for your responses. A colleague of mine just pointed out to me that there is nothing wrong with the original set-up. Equations are doing what they are supposed to do. In other words, from the engineering standpoint, results are what is expected and excel formulas reflect this as...
I tried both of your sugestions. It was already in AUTO and F9 did not recalculate. Here is what I have:
C23 21
C24 2
C25 4160
C26 0.015
C29 =((C23*1000000)/C25*1.732*100)/C24
C32 =C25*C29*1.732*0.000001*0.707*0.707
My initial question had...
I am stumped on what seems like a fairly simple calculation using a spreadsheet. I have four vertical user boxes for input of variables. Call them C21, C22, C23 and C24. In C25 I have an equation that uses information from the previous four cells to calculate an answer for C25. Then I have...