# Thread: Can someone explain the difference between phases and poles??

1. ## Re: Can someone explain the difference between phases and poles??

Originally Posted by JLMCDANIEL
Canuk,
Wake Kent up.
There is a significant difference between split phase and phase shift. Because the windings are in the same direction the phase pattern of the two windings are identical. If you ground the bottom line rather than the center tap and you read from the bottom line you would see the center tap to 120 RMS and the top leg go to 240 RMS at exactly the same time, reverse at the same time and go to the same RMS value in the opposite direction. That's because it is single phase. Because you change you reference point does not create a phase shift.
Jack
Yep ... you're absoluetly correct .... I did say shift and stand corrected using the wrong term.

Darn ... now I have to edit the post .... geez ....all this theory is giving me a head ache .... time for a nap.

2. ## Re: Can someone explain the difference between phases and poles??

Originally Posted by JLMCDANIEL
It would appear that you have a grounded high voltage system coming to the transformer. In other words it is using ground for the return. I have never seen that around here.
Jack
It's the same here.

I'm not sure if it's the same as what's called Single Wire Earth Return (SWER).

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## Re: Can someone explain the difference between phases and poles??

well I guess I need to stay in commercial and industrial three phase systems. I do understand the drawings but it blows me away. Thanks for the explaning it to me Jack.

Ulike our little Blue friend that knows it all. I'll admitt when I learned something new. I wish I knew it all

Canuk did you take that picture in the US? Ther is no snow on the pole......Up Nort they have snow all the time don't they?

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## Re: Can someone explain the difference between phases and poles??

Originally Posted by canuk
It's the same here.

I'm not sure if it's the same as what's called Single Wire Earth Return (SWER).
yep same thing which is what i was saying and many of you quoted but didn't 'get'. the medium voltage feeder single phase primary is connected line to ground which is a very common and cost efficient (less wire fewer poles per mile) way for utilities to deliver medium voltage single phase power further stepped down to 120/240 volts AC split-single phase power to residences and is done all over rural areas in north america.

ravens to answer your ? about why distribution to these single phase wire earth return lines are safer fed by secondary wyes just yourself what happens when delta loses one of its legs in the wiring scheme. that's the 'why' about 'why' the last split to secondary single phase feeder taps are done "wye" the substation with switch gear nearest us is delta primary wye secondary.
Last edited by Blue RidgeParkway; 09-16-2008 at 02:14 PM.

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## Re: Can someone explain the difference between phases and poles??

Originally Posted by Blue RidgeParkway
yep same thing which is what i was saying and many of you quoted but didn't 'get'. the medium voltage feeder single phase primary is connected line to ground which is a very common and cost efficient (less wire fewer poles per mile) way for utilities to deliver medium voltage single phase power further stepped down to 120/240 volts AC split-single phase power to residences and is done all over rural areas in north america.

ravens to answer your ? about why distribution to these single phase wire earth return lines are safer fed by secondary wyes just yourself what happens when delta loses one of its legs in the wiring scheme. that's the 'why' about 'why' the last split to secondary single phase feeder taps are done "wye" the substation with switch gear nearest us is delta primary wye secondary.
Huuu please explain it again please I do not understand what you are saying....it isn't very clear

6. ## Re: Can someone explain the difference between phases and poles??

Originally Posted by Blue RidgeParkway
yep same thing which is what i was saying and many of you quoted but didn't 'get'. the medium voltage feeder single phase primary is connected line to ground which is a very common and cost efficient (less wire fewer poles per mile) way for utilities to deliver medium voltage single phase power further stepped down to 120/240 volts AC split-single phase power to residences and is done all over rural areas in north america.

ravens to answer your ? about why distribution to these single phase wire earth return lines are safer fed by secondary wyes just yourself what happens when delta loses one of its legs in the wiring scheme. that's the 'why' about 'why' the last split to secondary single phase feeder taps are done "wye" the substation with switch gear nearest us is delta primary wye secondary.
I'm not sure where you come up with SWER being very common, at least in this country. Or that it is used all over rural areas in North America unless you mean rural areas in Canada.

Jack

7. ## Re: Can someone explain the difference between phases and poles??

Originally Posted by Blue RidgeParkway
rick and djohns,

your single phase pole transformer picture: that's normal here for single phase feeder line stepped down to single phase service. the HV primary is connected line to ground. usually grounded on the case of the tank it is prolly also strapped to the secondary neutral terminal on the side of the tank.. the utility pole is earthed to ground. the ground is prolly down the pole on the other side and prolly stops about 3 inches or so above the transformer lid. if you look at wires coming from the center secondary and follow them up and around you'll prolly see the top of the ground/netural termination on the pole. and see straps on the case connected to the secondary neutral tap.

yep same thing which is what i was saying and many of you quoted but didn't 'get'. the medium voltage feeder single phase primary is connected line to ground which is a very common and cost efficient (less wire fewer poles per mile) way for utilities to deliver medium voltage single phase power further stepped down to 120/240 volts AC split-single phase power to residences and is done all over rural areas in north america.

.
Well to be clear .... you hadn't mentioned SWER once.
Suddenly when I mentioned it you're all over it.

BTW .... you forgot to mention in .... ummmm ...... you say .....your description of SWER ....... it's used widely in Australia , New Zealand , Canada (Saskatchewan) along with a few other countries.

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## Re: Can someone explain the difference between phases and poles??

Originally Posted by JLMCDANIEL
I'm not sure where you come up with SWER being very common, at least in this country. Or that it is used all over rural areas in North America unless you mean rural areas in Canada.

Jack
my guess is that you aren't an active farmer in a real rural area and never heard of RUS.

9. ## Re: Can someone explain the difference between phases and poles??

Originally Posted by Blue RidgeParkway
my guess is that you aren't an active farmer in a real rural area and never heard of RUS.
Well actually if you check with our County Extension Office you will find farm number 151 lists me as sole operator. Have a DOA premises ID Number. I am a member of Mid-States Wool Growers Assoc., Ohio Lamb producers, Farm Bureau, among others. Have a lot of money tied up in farm equipment for not being active farmer. Live in a county with a total population of less than 29,000 with about half living in the city that is our county seat. Electric furnished by a rural electric co-op ( a Touchstone Co-Op) established under the REA, member of co-op for over 35 years. The Co-Op uses 2 wire not SWER, AEP furnishes electric about 3 miles down the road, still rural area, 2 wire service not SWER, about 5 miles away DP&L furnishes power, still rural area, 2 wire not SWER.

And what does the USDA Rural Utility Service have to do with it any way, they don't produce, provide, or deliver electric power.
Jack

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## Re: Can someone explain the difference between phases and poles??

Since there is so much posting going on here again, I'm gonna interrupt and ask a question that didn't get answered in a different thread. At least if it did..I didn't see it. Sorry for the interuption, but this is driving me nuts and I'm just sure that one of you has an answer for me.

Here goes once again...

Anybody know how to get this nasty printing ink off my hands?

For those of you who are wondering "What the heck is this about ?"...please bear with me concerning this question. There IS an important reason I'm asking.....and no, I have not been drinking.
Last edited by goldhiller; 09-17-2008 at 11:56 AM.

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