I am receiving some conflicting information on a Wye-Wye transformer connection. Concerning a three transformer bank connected wye on the secondary side, should the neutral wire that connects all three transformers be grounded to the transformer tank lug of just the center transformer or should...
I represent a utility that serves a chip mill. The chip mill’s MCC room is served by a 1500 kVA, 4160/480V transformer. The MCC room has no main disconnect, just individual disconnects serving various equipment. The chip mill is asking us if they can install a protection relay in their MCC...
We recently received a re-manufactured 3 phase transformer with a HOXO connection on the secondary side. (The transformer is a 24940Y/14400 480Y/277 1500kVA transformer) I know that a lot of transformers have a removable link to separate the HO and XO connection. This particular transformer...
Just received a dissolved gas in oil analysis on a 2000 kVA 25kV/480V three phase transformer. Acetylene is 102 ppm and total combustible gas is 212 ppm. Having another sample pulled tomorrow. How dangerous a transformer do I have? Should it be de-energized immediately? From what I have...
I am writing an article about some of the history of the electric coops’ beginnings in the 1930s. Does anyone know for sure what primary voltage was used on the old REA distribution systems in the 1930s? I am guessing 7.2/12.47kV but I cannot verify that.
Hi Guys, first post on this forum.
I work for an electric distribution utility with a primary voltage of 14.4/24.9kV.
Recently, we had an outage on a 3Ø line involving only one phase… the other two phases remained “hot”. There are several banks on this line both Wye-Delta and Wye-Wye. The...
