Transformer vectoring

[spark and bark]

:D
hey, anyone REALLY use vectoring? We are learning it heavily at school, and it seems real simple, but some lineman say they have rarely used it in the field.(mind you, I am in northern idaho with few large industrial areas) Does anyone use it alot in the field? Is it helpful or is it easier to just build a new bank and then just flop legs until they brother with the old bank? Let me know! Any info is good!!

[west coast hand]

No you don't really use it in the field we just usally hang a new bank but it is good to know and all part of the apprenticship and learn all you can because you never know where you will work??? And maybe some of the non union hands can comment on this or do they not teach things like that or any electrical theory I'm just wondering not talkin smack (this time anyway)

[Chong]

it doesnt take long before you know how to build basic banks..wye and delta..without havin to sit dwn and draw vectors. But the vectors help you understand the hookups and there are some oddball banks out there. Its a tool for your bag,If you need its and dont have it..wellll.. I figure your either in Avistas school or the NWJATC, both good programs. Keep your ears..eyes..and mind open, ask questions listen to the answers. Lookup and live long

[Edge]

I'd rather build off a vector then a print... still gotta mate the legs if your paralleling...

I find the vector easy just look at it and hook it up...

saw a print one time on an open delta that had the wrong leg as the wild... woulda been a bitch if I had hooked it up that way...

for what it's worth

Edge

[tramp67]

Knowing vectoring can come in handy fairly often, depending where you work. Some guys I've worked with never build three phase banks, others do it all the time. It's good to be able to build your bank and have it be right the first time, the voltage checks just to double check your work. Sometimes you end up taking down a bank on a pole being changed out, and need to build a new bank on the opposite side of the pole. In a situation like this, you need to know how to build it right, since you are hooking up to an existing customer, and their voltage and rotation needs to be right. You also won't have anything to match up to, as far as checking for your zero voltages. Other situations, you will be rebuilding a bank that had been destroyed by a storm, and the customer will be able to tell you what they had, you will need to match it again. On larger banks with paralleled conductors, it can be real time consuming if you have to swap leads because you built the bank wrong. And then there's those oddball banks that don't seem to make any sense until you trace everything out, and when you build a new one correctly the first time, it may get you an attaboy to make up for a few ohsh#ts down the road!:p

[tramp67]

Another way of looking at it, I've seen a lot of stuff get burned up by guys that hooked things up wrong to a customer because they didn't understand three phase power well enough. On another occasion, a different crew hooked up a bunch of street lighting to a 480 volt single phase system, and they didn't know there was such a beast, so they burned up a whole bunch of new lights. It's just good to know for those times you may need it and don't have anyone else to turn to.

[spark and bark]

good to know guys!! It sure seems like it has a lot of uses, and a great tool to prevent some disasters!! Appreciate all the feedback

[BillyMac]

You fellas have a separate bank for each phase yeah? Over here we got a Single phase Tx 240v,which can be wired for dual phase if needed or just a larger TX that's 3 phase 415v. Buts we still got the same prob if a 3 phase shits itself and you don't know the rotation at the customers end.

[wudwlkr]

Reality is that most distribution linemen probably don't/can't do vectors. Their system has a couple of standardized hookups that are used and that's all the crews know. And then when an unusual situation comes up and they can't figure it out. That's when things blow up. Learn all you can now and keep reference material for future use. If you want to eventually get into a supervisor's position then the responsibility for making correct hookups will be on your ass and you are going to be damn glad you did know how to do the vectors.

[climbsomemore]

It's easier to learn the two families of connections... and understand how the length and direction of the windings produce voltage. Vectors are how most company standard manuals (plus all the factory training materials) explain how the connections work. You are way ahead if you learn to read the diagrams and understand how and why they work.

Of course... you could try to remember the 16 common, possible voltages we see in North America... plus all the other stuff about rotation and keep it in your head. Plus...once you understand the connections (wye and delta) it's just a hop, skip and a jump to learning how to connect generatiors and motors.

Thats just the 3 phase stuff... there are still a few old inner cities in North America that run a true 2 phase, 5 wire system. Those make a lot more sense if you understand vectors.

[T-Man]

Didn't have a clue what the heck I would use vectoring for when I started, then I became a Troubleshooter and it made some sense but I didn't need it that much. Once I became a dispatcher It was more useful to help the people I was dispatching to work out a problem, then I became a trainer and it was invaluable to use to show on paper or board how transformers work and how you wire the different voltages.

Now we use the 3DInternet virtual program (check it out http://3dinternet.com/) where you can set up a senario single phase or three phase and wire it, when you energize the bank, you can actually have a virtual blow if you didn't get it right. Or you can take voltage readings and your answers all make sense. You can phase primary and close secondary splits. The program works well for us and the younger generation used to computer gaming seem to get a better handle on vectoring from the get go. Your outfit needs to purchase licensing to get rights to use it. It's the future. . .

[NMSA122-G]

WOW!! That looks like a great tool.. (Seriously)

[PA BEN]

Been doing this for 26 years. WWP and Avista trained. If you know how to build a bank why use vectors? You people who say you need to know them give us a good example of where you need to know them?

[topgroove]

Been doing this for 26 years. WWP and Avista trained. If you know how to build a bank why use vectors? You people who say you need to know them give us a good example of where you need to know them?Comes in handy when paralleling two 4.8 kv delta feeders fed by different substations that have different transmission feeds. Even after closing one switch you still can have over a thousand volts across the remaining two. If you understand the vectors you can tell if you have a phase angle shift.

[T-Man]

One example is when you convert 8KV to 24.9 you put a step down in, to feed an 8Kv exisiting URD Subdivision. (you wouldn't rewire the subdivision unless it was too old) The feed in the subdivision is now called a ZX feeder and the vector for a Z is out of phase 30 degrees with the old X feeder vector. so if the job is not copmplete and half the subdivision is fed from ZX and the other half is X the bridging point in the center will not phase. You have to take an outage to close this point. Vectoring in class and sometimes as a reminder for the cats doing the work in the field, helps them understand why they are unable to get zeros at the bridging point and read about 30 degrees out of phase.
It also comes in handy doing this work when they get the wiring on the step downs wrong and backfeed one from the closed bridging point.

Another example is when you take out a defective 4800volt Overhead transformer and close bridging. When you install the new tub if you dont phase it to the secondary you can develope twice the primary voltage
9600volts across the cutout and it fails and you have glass blowing in every direction, a vector can be drawn to illustrate why this can and will happen.

[PA BEN]

Comes in handy when paralleling two 4.8 kv delta feeders fed by different substations that have different transmission feeds. Even after closing one switch you still can have over a thousand volts across the remaining two. If you understand the vectors you can tell if you have a phase angle shift.
TP, What about a Phasing set?

T-Man, So you're saying if I don't pay attention and wire it wrong and it blows up I can draw out a vector to see why it happened? BTW, I'm not a substation tect. If I work a sub. I do it beside the tect. and engineering draws up my work.

[T-Man]

Not substations. In exsisting residential subdivisions fed by 8 KV we may upgrade to 24.9Kv on the main line out on the road, then where we feed the subdivision we step the 24.9KV down to 8KV and this step down voltage has a different vector than the 8KV does. So you could wire correct all day long it will never go togerther. If you had a handle on the vectoring or knew someone who did they could help you. If you get along without good for you but there are some people that need a deeper understanding. In a classroom it's hard to show why the system works the way it does with out vectoring.

[lewy]

We also do not use vectors when hooking up banks. Fortunatly we do not parallel secondarys, but I know enough that the transformers would have to be fed by the same primary voltage & phase & circuit & be the same secondary voltage. I would also take a voltage check first. When we parallel on our primary we have our system operators match voltages for us. We have a few places where the primary goes from 28kv to 8 kv through a rabbit & we know that we cannot parrallel them.

[topgroove]

TP, What about a Phasing set?

T-Man, So you're saying if I don't pay attention and wire it wrong and it blows up I can draw out a vector to see why it happened? BTW, I'm not a substation tect. If I work a sub. I do it beside the tect. and engineering draws up my work.

I could show you several spots in our system where you can go up with a set of phase sticks and swear there's no way in hell you'll be able to close the switches. 4.8kv delta can get kinda strange. you can in get 4800 volts across a switch from two feeders feed by different substations . you can close one switch its called "marrying the feeders" and than test across the other two switches. if the voltage is less than 480 volts its safe to close the other switchs. A couple times i've had over thousand volts across the remaining switches and we had to draw the vectors out to make sure we didn't have a phase angle shift. both cases we got the switches closed. On the other hand any time you go from a wye to a delta or a delta to a wye you'll get a 30 degree phase angle shift

[Lineman North Florida]

We don't use vectors either and I have built banks all over the SE U.S. and never had any problems, know how to swap rotation high side or low side and know how to get it right without having to swap anything during a bank changeout, remember a little about vectors during my apprenticeship but have been able to get by without it, maybe just extremely lucky, on the other hand have done very little delta primary work as we don't have any and have seen very little of it down here in the South, ran into some in Louisville Kentucky a few years ago and it was about the rattyiest mess I have ever seen,looked like it was from the 1930's, glad we don't have it down here.

[PA BEN]

T-man, Its good to see whats going on w/victors yes, in the class room. TP it all boils down to knowing your job. You knew at the time you would get a difference across the switch. If I ran into that in the field and didn't know about the difference, and questioned it, vectoring wouldn't be my answer, I'd stop and make a call. Training at your Utility. BTW, I've only worked Wye systems. Good discussion, as lineman it's good to keep on top of situations we run in to out in the field.;)

[T-Man]

But if any of you are interested in more info on that 3DInternet transformer program the person to contact is Kevin Simkins at:

http://www.3dinternet.com/
Phone: 312-208-0852 cell / 847-699-4800 office
Email : kevin@3dinternet.com or kevinsimkins@hotmail.com

It works very well for our training.