Different Answers

[reppy007]

Heres the deal..in this area electricity is generated from the plant in this order..C-B-A...so when out in the field how can you determine the rotation of a given bank if your going to check rotation at the meter.....before answering think about the different types of meter cans or switch boxes located before the meter,some like a 420 roll inside the switch box.....Ive tried several ways and didnt quite get my hands on this due to the load of work that was handed to me. Now if the bank was already energized thats pretty much easy if its like behind a strip center....but this would be a new installation....Ive tried looking at the in-coming phases and wiring the secondary in those orders and found that it still was a 50/50 shot as to getting the rotation that I wanted at the meter.Its one thing I didnt quite perfect.... it wasnt like every meter order was feeding from an overhead bank,and it wasnt like all the orders were 3/0

[lewy]

Heres the deal..in this area electricity is generated from the plant in this order..C-B-A...so when out in the field how can you determine the rotation of a given bank if your going to check rotation at the meter.....before answering think about the different types of meter cans or switch boxes located before the meter,some like a 420 roll inside the switch box.....Ive tried several ways and didnt quite get my hands on this due to the load of work that was handed to me. Now if the bank was already energized thats pretty much easy if its like behind a strip center....but this would be a new installation....Ive tried looking at the in-coming phases and wiring the secondary in those orders and found that it still was a 50/50 shot as to getting the rotation that I wanted at the meter.Its one thing I didnt quite perfect.... it wasnt like every meter order was feeding from an overhead bank,and it wasnt like all the orders were 3/0For new installations they are responsible for there rotation, after that we have to keep it the same.

[Lineman North Florida]

Reppy on our system when you make up a new 3 phase padmount tx your going to get clockwise rotation if the primary is made up right, when I say right I mean A phase to H1A, B phase to H1B, and C phase to H1C, if you don't have clockwise rotation you have something wrong ie" crossed phases in a splice pit, tapped up wrong on the pole etc, etc. Same goes for building a new overhead wye bank, if it's made up right it's gonna be clockwise.

[lewy]

On all of our 3 phase transformers they come labeled H1A H2A H3A on the left & H1B H2B H3B on the right. We mark all our phasing by colour & we always go Red White Blue top to bottom. The electrician is responsible for the secondary connections in our 3 phase transformers on a new connection, he has to give us a meggar report as well as torque them, so the rotation is up to him.

[rob8210]

When we build power banks we wire them up to match the primary phasing, if possible. Then we take a phase rotation and make connections based on that . I have worked in spot were we could not find any phase marking at all on the primary. Recently I traced one feeder right back to the substation just to make sure the parallel tie switch we were installing would be in phase. That utility told us phase marking had never been a priority with them.