One for the Swimpy.

[wtdoor67]

Greg, you stated once you enjoyed the little "scenarios", I used to put up. They were 90% just real things that had happened to me in this trade. However I'll give you one that is a "scenario" if you will.

You are running a distb. crew. According to the work order you are to build a bank of overhead transformers that will give the customer 120/208 three phase service. Of course a combo bank that will give 120 volt single phase and three phase 208 volts.

You glance at the material sheet and notice all the usual items, the transformer order says 2400/4160 primary and 120/240 secondary. You have the hands take the material sheet, locate where the stores guy has spotted the material, and load it on the linetruck. This goes on an existing pole and all you'll have to do is hang the bank, run the service and heat it up, check voltage and open the cutouts and leave if the meter base hasn't been inspected. If it has you just set the meter, seal it and close and leave. Whatever.

This stretch of primary, you're familiar with and it's a 4160 volt unigrounded area with the neutral of the Wye not present. The hands load the material while you do a little paperwork and perhaps coordinate with the local serviceman to set the meter or whatever is standard at this entity. After about 30 minutes you get in the linetruck with the App. driving and with the Jman following in the bucket you drive to the location where a short tailboard is held and you commence.

Your thoughts on this please Gregg. All others please give Gregg time to PM his friends, and do not chime in until Gregg has answered.

[wtdoor67]

Most people call such systems by whatever their local entity calls them. An ungrounded Wye would be a name that I have heard them called. Of course the prefix uni usually means one or something similar.

Your answer isn't correct in that it isn't workable. What you suggest wouldn't work. Yes you could drag in another wire for a neutral but some of these systems would require several miles of wire.

I have worked on quite a bit of secondary that is somewhat like triplex but it has a small alum or some kind of alloy ribbon wrapped around it just to keep it together. It is midspan tapped etc. if needed. I have heard it called "bundle secondary", "parallel lay", and "cable secondary" and one other name I have forgot. All the same stuff. Generic names are sometimes hard to find.

Let some of the "sharpies" guess. Someone will come up with it.

[wtdoor67]

We did a combination reconductor once. Replaced 6 A3 conductor with 477 acsr. Eventually we had all the old wire laid out, the new wire strung in, sagged and heated up. The old circuit was 4160 with a neutral and the new was 12470 with a neutral. Everything was bumped to the new circuit with pots changed etc.

We lacked one 3 pot 120/240 bank to change over. This bank served a dairy queen. It was hot summer and they were doing a land office business. When it was broached to the manager about perhaps being off for about 45 minutes to an hour she became extremely angry and of course said she would bitch to high heaven etc. We never did any midnite outages per se as everybody that worked on the crew lived at different directions and quite a distance from the job. It would have to have been extreme before this rat contractor would have put us up in a motel and paid for our meals on a small item like this.

The 3 phase tap that served the dairy queen ran at a 90 degree to the feed. One end (about 2 spans ) served a single phase gas station (it was still 4 KV) and the opposite end (about 2 spans) went to the dairy queen. The bank was on the deadend.

We came up with a plan that only caused about a 2 minute outage. There was single phase open wire secondary coming about 3 spans from the single phase pot. That's my only hint. You take it from there.

[SwampRat JR.]

You build a 240 v power bank, and ya use the X2's.

[Edge]

I'm kinna thinkin you mean UNgrounded Wye....Not UNI grounded wye...

T

no...

not un grounded wye...

there a big fugging difference between a ground and a neutral... uniground is a much better term...

the best term is

SWER...


and as far a stringin in new neutral conductor.... yeah like door said.... some of that shit runs for MILES...

for what it's worth...

Edge
or single wire earth return... I'm sure CL can chime in on this theres tons of that shit up in da great white note ehh?

I spent years up in and around oiltown cuttin that shit over to true wye...

and theres still a pile of that shit down here in the states too... and is often confused for delta and is in to way such a thing....

[west coast hand]

I bet you guys used the secondary neutral as the primary neutral for the bank.and cut the cans over ac/bd...

[Edge]

I bet you guys used the secondary neutral as the primary neutral for the bank.and cut the cans over ac/bd...

yeppers tie them all togeather and runnn them down the stick with some # 2 or better... to a muti ground rod system or a grounding cage usually works... I didn't answer cuz I thought it was swimpys question

[SwampRat JR.]

First I would have told the bitch tough shit, but what he probably did is built a bank on the one end where the gas station was, then he used the open wire a quad for the three phase secondary, got rotation at DQ, heated up the new bank at 7200, ran the the new voltage with through the open wire, matched like legs with his volt meter, took a short kill on the DQ, made three connections, heated them up, then tore down the old bank, heated the line to DQ to 7200, built a new bank, when they had the right pots, parralled them with the exsisting, then cut it over, then wrecked out the old open wire.

The secret password is parlay Danny, parlay.

[west coast hand]

yeppers tie them all togeather and runnn them down the stick with some # 2 or better... to a muti ground rod system or a grounding cage usually works... I didn't answer cuz I thought it was swimpys question


We all know how swimpy is not the sharpist tool in the bin...come on drag a primary neutral for a bank LOL why not just run a pole ground dumb ass...I new the answer when I first read the thread but waited for DA to reply and when I seen he was WRONG I had to jump in...He's probaly still on the phone or computer tryin to figure it out... LOL

[Edge]

The 3 primary phases were pulled off a 7200/13.2 Wye circuit to the bank out in a cow pasture.

odd...

guess 1.73 ain't worth a fu(k

Bill

and your bank was prolly a fuggin wye/delta... it looked to be wired delta high side but in fact the neutral was floatin.... why pull in a span of conductor thats not even needed?

[Edge]

First I would have told the bitch tough shit, but what he probably did is built a bank on the one end where the gas station was, then he used the open wire a quad for the three phase secondary, got rotation at DQ, heated up the new bank at 7200, ran the the new voltage with through the open wire, matched like legs with his volt meter, took a short kill on the DQ, made three connections, heated them up, then tore down the old bank, heated the line to DQ to 7200, built a new bank, when they had the right pots, parralled them with the exsisting, then cut it over, then wrecked out the old open wire.

The secret password is parlay Danny, parlay.

right there with ya Jr... damn your smarter than your old man...

[wtdoor67]

If you lay it out piece by piece, it makes it too simple. No fun.

Only trouble is most people want to get complicated. I've heard of those places in Canada where you can just slap down a ground, but the areas of the continent where that's possible aren't common. And yeah I've seen the just put up a piece of wire in the middle of nowhere, start driving grounds rods and go with that for a neut. I never thought it Kosher but it'll work.

Maybe a little tricky on the first one, but not really. What you're gonna do everywhere I've worked is go with your phase to phase voltage. I've seen this system on 4160, 12470, 13.2 and 20.8. All ungrounded Wye or whatever. First off a pot marked 2400/4160 will not work hooked delta on the high side. Saw that tried once. Kaboom! Kaboom! Only 2400 turns won't stay hitched phase to phase. Gotta have pots with more windings. The ones we used were marked 4160/7200. Delta/Wye hookup. Probably AC/BD them alright. Could work without that but you'd waste half the windings. Plain old Delta/Wye hookup with 4160/7200 pots.

On the DQ thing here's what we did. JR's plan sounded pretty close. We hung a power pot one span of the DQ bank. Ran some triplex from it to the open wire secondary fed by the single phase pot, and hooked it into the power pot, from the power pot to DQ, a piece of quad. Made a 2 pot split bank and phased it together with the DQ bank. At this junction with the 2 pot bank paralleled with the 3 pot bank we opened the 3 pot bank, pulled the pot leads out and taped them in the clear.

Then the 7200/12470 pots were hung and "backed" in. By this I mean you stuck each lead into the secondary leads of the new pots with the cutouts open. Makes a good spark so be prepared. Only thing here is make sure the new pots are all good. Can test them at the 4 KV voltage and see if they're good. Nowadays can use a pot tester.

At this point all that remains is to kill everybody, one man at the split bank lighting pot, one at the split bank power pot, one standing by at the new DQ bank ready to close and last but not least one guy in a bucket ready to cut the jumpers at the junction pole. Old Ish here was that guy. On signal the split bank pots were opened, I cut the jumpers on the laid out 4 KV, took some rubber mechanicals, ran them from the new 12470 circuit to the newly de-energized wire. Got in the clear and signaled for the guy at the DQ bank to close in and hope the rotation was right. We got lucky. It was good. This left the split bank pots that were 2400/4160 backfeeding. With care the single phase pot was taken down and replaced with a 7200 pot, phased together and closed. Then separated and then just dismantle all the temp. quads, triplex and power pot. It's been a while back but I bet the total outage to the DQ was no more than 2 minutes.

[Edge]

If you lay it out piece by piece, it makes it too simple. No fun.

Only trouble is most people want to get complicated. I've heard of those places in Canada where you can just slap down a ground, but the areas of the continent where that's possible aren't common. And yeah I've seen the just put up a piece of wire in the middle of nowhere, start driving grounds rods and go with that for a neut. I never thought it Kosher but it'll work.

Maybe a little tricky on the first one, but not really. What you're gonna do everywhere I've worked is go with your phase to phase voltage. I've seen this system on 4160, 12470, 13.2 and 20.8. All ungrounded Wye or whatever. First off a pot marked 2400/4160 will not work hooked delta on the high side. Saw that tried once. Kaboom! Kaboom! Only 2400 turns won't stay hitched phase to phase. Gotta have pots with more windings. The ones we used were marked 4160/7200. Delta/Wye hookup. Probably AC/BD them alright. Could work without that but you'd waste half the windings. Plain old Delta/Wye hookup with 4160/7200 pots.

On the DQ thing here's what we did. JR's plan sounded pretty close. We hung a power pot one span of the DQ bank. Ran some triplex from it to the open wire secondary fed by the single phase pot, and hooked it into the power pot, from the power pot to DQ, a piece of quad. Made a 2 pot split bank and phased it together with the DQ bank. At this junction with the 2 pot bank paralleled with the 3 pot bank we opened the 3 pot bank, pulled the pot leads out and taped them in the clear.

Then the 7200/12470 pots were hung and "backed" in. By this I mean you stuck each lead into the secondary leads of the new pots with the cutouts open. Makes a good spark so be prepared. Only thing here is make sure the new pots are all good. Can test them at the 4 KV voltage and see if they're good. Nowadays can use a pot tester.

At this point all that remains is to kill everybody, one man at the split bank lighting pot, one at the split bank power pot, one standing by at the new DQ bank ready to close and last but not least one guy in a bucket ready to cut the jumpers at the junction pole. Old Ish here was that guy. On signal the split bank pots were opened, I cut the jumpers on the laid out 4 KV, took some rubber mechanicals, ran them from the new 12470 circuit to the newly de-energized wire. Got in the clear and signaled for the guy at the DQ bank to close in and hope the rotation was right. We got lucky. It was good. This left the split bank pots that were 2400/4160 backfeeding. With care the single phase pot was taken down and replaced with a 7200 pot, phased together and closed. Then separated and then just dismantle all the temp. quads, triplex and power pot. It's been a while back but I bet the total outage to the DQ was no more than 2 minutes.


at least someone got the 1.73 reference...

yeah tahts a sweet way of doing the DQ also 'door the thing about jr.s post is that in theory there could have been no outage at all...

you could have built the bank at pole 2 cut loose the leads from the open wire at the gas station... phased into the sec.s at the DQ and hooked the bitch up hot...

depends on how funky you wanna get...

and as far as the dirt return???

sorry Danny there's places all over Pa. in older towns where it works in blue granite...

funny thing about electricity... it's gotta get back to where it came from...

our job is to just make sure it gets home...

Bill

[wtdoor67]

There's always different wrinkles. I've seen secondaries paralleled that had different primaries. We've spoken about it before. 4 KV secondaries of 120/208 matched with 12 KV secondaries of 120/208. I've seen secondary coming from a 115 transmission matched with a secondary from 57 KV. Both secondaries 7200/12470 with two subs paralled. The 57 KV originated from a govt. dam and the 115 originated from a power co. coal powered plant. Sometimes I think about anything is possible but now and then you have a boo boo.

I remember once after a storm. Everything had been back to normal for about 6 months. A crew was sent to close some NO switches. Phasing wasn't checked closely after the storm and evidently someone had rolled one circuit completely. Rotation not changed but the phasing all 100% wrong. When the crew closed the NO solid blades they locked out the circuit. I wasn't involved and sorta thought it was funny cause one guy on the crew bitched to high heaven and threatened to quit. He didn't. I guess it could have been bad, depending if you were the one doing it. Bet that's happened several times in different places. These damn power co's. Ever day's a new day for them. Make the same mistakes over and over.

[wtdoor67]

Most don't seem to realize it, but a 3 pot Wye/Delta don't need a primary neutral. I've seen people on trouble with a bank on a dead end with the neut. down, kill the bank and dink around getting that yanked down neutral back to the dead end. Didn't have heart to tell um.

Like that old crazy guy I worked with used to say. "I'm so damn smart I make myself sick". Course he had a lapse and backfeed got him.

[Edge]

[quote=Edge;81990]and your bank was prolly a fuggin wye/delta... it looked to be wired delta high side but in fact the neutral was floatin.

Yeah....
You're probably right.
My fu$kin eyes are shot to shit too.:D

you answered it yourself...

for what it's worth...

Edge

[SwampRat JR.]

Danny, ya said 208 three phase, thats a Y voltage, ok, and like you guys are saying, windings are windings, ratios are ratios, 1.73 is 1.73, come on man.

Like Edge is saying to, you can do all sorts of shit to keep outages short ect, cut overs are cut overs, but most places are not gonna have a crew do all that shit, unless it is a big customer, a DQ WTF. You can always keep that dead squirrel in that plastic bag blame it those little bastards, or you can always tell them you can get the power from the line across the street.

Good to see talk about linework though, and it is always more fun for us to make it all happen without them knowing we were there at all.

[rcdallas]

Most don't seem to realize it, but a 3 pot Wye/Delta don't need a primary neutral. I've seen people on trouble with a bank on a dead end with the neut. down, kill the bank and dink around getting that yanked down neutral back to the dead end. Didn't have heart to tell um.

Like that old crazy guy I worked with used to say. "I'm so damn smart I make myself sick". Course he had a lapse and backfeed got him.

Alright cowboy, you write some interesting shit, a lot I know your talking about is true such as getting 120/208 using only half the windings with out cutting them over... that's pretty simple just going phase to phase. I don't know delta system's very well since I've never worked with one, nor have I had any instructors that really knew much about them as well.

But seriously, educate me on this... Let's say specifically 3 Pot Floating Wye-Delta 7200/12470-120/240 3 phase 4 wire bank...say 2 15kva power pots along with a 37.5 lighting pot wouldn't need a system neutral?

Wouldn't their be some imbalance between the phases? If on your lighting pot you have 30 amps on one leg, 50 on another, you still wouldn't need a neutral? Really I just don't see it.

Now I can see it on a 3 phase 3 wire 480 bank...we have some of that here in the oil field where the customer would sign off on specifically not having a grounded leg...only reason I heard is the customer claims to get a "stronger voltage".

I pick the shit out of people's brains, but haven't came across that yet...

[SwampRat JR.]

Alright dipshit, 7200 x 1.73 = 12456 not 13,200 savy, 4160/1.73 = 2,400 savy.

There is alot of three wire Y primary, pole grounds are drivin, you can still hook up a Y, Delta, 120, 240, 208 bank, also a strait 240, or 480 bank, but a 208, or 277/480 bank you need to have a primary neutral.

Danny, on a 7200/12470 3 wire primary, if you built a Y, Delta 240 volt bank, did not ground X2 on a any three of your pots, then used X2 for your hot legs, what would your phase to phase voltage be, and phase to dirt be?

[wtdoor67]

233 reads on this thread.....
And I ain't heard yet....except for "kaboom"... Why wirin the primary, Delta on the high side of your senario...wouldn't work. When....I've seen it, and done it.
-------------------------------------------------------------------------

Okay Gregg. It depends on the amount of turns on the primary windings of the pots. For example; A pot labeled 7200/12470 has 7200 turns on the primary. If you hang it in a bank and hook the high side delta in a 12470 phase to phase circuit, and close the cutout it will blow the fuse. I've seen it done.

If you take a pot marked 2400/4160 that means it has 2400 turns on the primary winding. If you hang it in a bank and hook the high side delta in a 4160 phase to phase circuit, and close the cutouts, it will blow the fuse. I've seen it done.

Many folks forget that pot label order gives a message. If the label reads 12470/7200 it is a single bushing pot. If the label reads 7200/12470 it is a double bushing pot suitable for 3 pot banks.

Some people get hung up on these unigrounded or ungrounded wyes or whatever you want to call them.

There is one exception though. For a 3 pot Wye/Delta bank the lower rated pots will work where the neutral is "floated". I have seen just a few spans apart in the same circuit, banks with the same secondary voltage with the first bank hooked Wye/Delta and the second bank hooked Delta/Delta. Of course the labels on the first bank said. 7200/12470 and on the second bank. 12000/20800. For 2 pot banks, single pots and Wye secondaries you are going to have to use the 20.8 pots.

[wtdoor67]

Alright dipshit, 7200 x 1.73 = 12456 not 13,200 savy, 4160/1.73 = 2,400 savy.

There is alot of three wire Y primary, pole grounds are drivin, you can still hook up a Y, Delta, 120, 240, 208 bank, also a strait 240, or 480 bank, but a 208, or 277/480 bank you need to have a primary neutral.

Danny, on a 7200/12470 3 wire primary, if you built a Y, Delta 240 volt bank, did not ground X2 on a any three of your pots, then used X2 for your hot legs, what would your phase to phase voltage be, and phase to dirt be?

Jr. on such a getup, you would have 2 separate circuits of delta. One would be 240 volts phase to phase and the X2 one would be 120 volts phase to phase. Phase to ground would greatly vary as any ungrounded delta would. We had some banks exactly as you describe except they were twice the voltage. One circuit of 240 and one of 480.

We had several ungrounded delta irrigation banks. At least 3 times each summer we would get calls from electricians saying there was something wrong. They were checking with a voltmeter phase to ground on those ungrounded banks and getting wild readings. We told em, don't sweat it.

[wtdoor67]

I once got hung up on the very same question you have. I asked an engineer that I trusted. Where in hell does the imbalance go on these Wye/Delta banks when there is no system neutral brought out? His reply. Well it just kinda goes round and round in the delta. I didn't think that was a very good answer but it's partially true. Some of the imbalance goes back on the phases themselves.

In these ungrounded Wye systems as I explained to Swimp, it's not unusual to see a Wye/Delta bank and a Delta/Delta in the same area or circuit.

Nobody ever takes my advise on books but here goes. I checked at Barnes and Noble and they had several of these used books for sale. About 10 bucks. It's an old engineering book first put out in 1954. Most of the info is valid and you'll find answers to a lot of your questions.

The book title is "Electric Transmission and Distribution" and the editor is Bernhardt G. A. Skrotzi. Buy a copy and see what you think.

[rcdallas]

233 reads on this thread.....
And I ain't heard yet....except for "kaboom"... Why wirin the primary, Delta on the high side of your senario...wouldn't work. When....I've seen it, and done it.
-------------------------------------------------------------------------

Okay Gregg. It depends on the amount of turns on the primary windings of the pots. For example; A pot labeled 7200/12470 has 7200 turns on the primary. If you hang it in a bank and hook the high side delta in a 12470 phase to phase circuit, and close the cutout it will blow the fuse. I've seen it done.



Oh yeah...need a pot labeled strictly 12470 OR 12470/21600...if you wanna hook up delta on the high side on a 7200/12470 system.

[rcdallas]

I once got hung up on the very same question you have. I asked an engineer that I trusted. Where in hell does the imbalance go on these Wye/Delta banks when there is no system neutral brought out? His reply. Well it just kinda goes round and round in the delta. I didn't think that was a very good answer but it's partially true. Some of the imbalance goes back on the phases themselves.

In these ungrounded Wye systems as I explained to Swimp, it's not unusual to see a Wye/Delta bank and a Delta/Delta in the same area or circuit.

Nobody ever takes my advise on books but here goes. I checked at Barnes and Noble and they had several of these used books for sale. About 10 bucks. It's an old engineering book first put out in 1954. Most of the info is valid and you'll find answers to a lot of your questions.

The book title is "Electric Transmission and Distribution" and the editor is Bernhardt G. A. Skrotzi. Buy a copy and see what you think.

I'll check into that... I have this geeked out ben stein trainer that I constantly throw shit like that out at him...I'll bring that up.

Thanks for the info on the book.

[west coast hand]

I came up on mostly delta systems and anytime we hang a bank that has a delta primary side they say 4160 or 12000 or 16000 the single phase pot are the same way exept the 4 kv those are 2400/4160 most of the 4 out here has a Nuet but is usally only grounded at the sub

[Edge]

Jr. on such a getup, you would have 2 separate circuits of delta. One would be 240 volts phase to phase and the X2 one would be 120 volts phase to phase. Phase to ground would greatly vary as any ungrounded delta would. We had some banks exactly as you describe except they were twice the voltage. One circuit of 240 and one of 480.


yeppers did a job years ago that was supposed to be a 240 bank the utlity had a bunch of 7.2 and had been cutting over a pile of their heavy load areas to 14.4 so they a a shit pot of duel voltage pots...
we got to the job and realized the warehouse guys had loaded us 480 pots

since we were working on a 7.2 circuit the foreman wanted to hook it up like normal and put the tap on step one (14.4) to run all the windings on the high side so the sec sides would be 240 I told him that was a fuggin death trap cuz they utlity cout cot that bank over in the future and when they did some one would think the pots had allready been tapped and when they brount the primary back up to 14.4 the sec.s would be 480 and some shit would get burnt the fu(k up...

I wired it up as you mentioned and as far as I know the sob is still there...

for what it's worth...

Edge

ohhh and that is a great book Danny I got it in my library too.... guess I should blow the dust off it... I missed the name plate thing too... but I was still getting over Swimpys 7.2/13.2

[Edge]

Ya THINK...bastard child?:rolleyes:

Secondary voltage...is created by the induction of Primary voltage on the Coil of the transformer. Windings are windings. The COIL off the transformer, does what it does...by the voltage induced, and the windings it has.

We still need to assertain...the "essence" of Danny's post.
Can the bank be hooked up...Delta on the high side?...In danny's sererio and work?

"You are running a distb. crew. According to the work order you are to build a bank of overhead transformers that will give the customer 120/208 three phase service. Of course a combo bank that will give 120 volt single phase and three phase 208 volts.

You glance at the material sheet and notice all the usual items, the transformer order says 2400/4160 primary and 120/240 secondary. You have the hands take the material sheet, locate where the stores guy has spotted the material, and load it on the linetruck. This goes on an existing pole and all you'll have to do is hang the bank, run the service and heat it up, check voltage and open the cutouts and leave if the meter base hasn't been inspected. If it has you just set the meter, seal it and close and leave. Whatever."

Okay Gregg. It depends on the amount of turns on the primary windings of the pots. For example; A pot labeled 7200/12470 has 7200 turns on the primary. If you hang it in a bank and hook the high side delta in a 12470 phase to phase circuit, and close the cutout it will blow the fuse. I've seen it done.

If you take a pot marked 2400/4160 that means it has 2400 turns on the primary winding. If you hang it in a bank and hook the high side delta in a 4160 phase to phase circuit, and close the cutouts, it will blow the fuse. I've seen it done.

Many folks forget that pot label order gives a message. If the label reads 12470/7200 it is a single bushing pot. If the label reads 7200/12470 it is a double bushing pot suitable for 3 pot banks.

Some people get hung up on these unigrounded or ungrounded wyes or whatever you want to call them.

There is one exception though. For a 3 pot Wye/Delta bank the lower rated pots will work where the neutral is "floated". I have seen just a few spans apart in the same circuit, banks with the same secondary voltage with the first bank hooked Wye/Delta and the second bank hooked Delta/Delta. Of course the labels on the first bank said. 7200/12470 and on the second bank. 12000/20800. For 2 pot banks, single pots and Wye secondaries you are going to have to use the 20.8 pots.

in theory it can be done Swimpy but like 'door says alot of times the pots won't hold it...

I've seen it go both ways... the other thing about the labels some folks don't get 7200/12470 phase to dirt 7.2 is wye hook up 12470 is delta hook up...

heres a pretty cool link for ya to ummmm "brush up"

http://insayne_kokane.tripod.com/transformers.shtml

damn it man I just learned to google! this kicks ASS!!!

for what it's worth...

Edge

[MI-Lineman]

Okay Gregg. It depends on the amount of turns on the primary windings of the pots. For example; A pot labeled 7200/12470 has 7200 turns on the primary. If you hang it in a bank and hook the high side delta in a 12470 phase to phase circuit, and close the cutout it will blow the fuse. I've seen it done.

If you take a pot marked 2400/4160 that means it has 2400 turns on the primary winding. If you hang it in a bank and hook the high side delta in a 4160 phase to phase circuit, and close the cutouts, it will blow the fuse. I've seen it done.

Many folks forget that pot label order gives a message. If the label reads 12470/7200 it is a single bushing pot. If the label reads 7200/12470 it is a double bushing pot suitable for 3 pot banks.

Some people get hung up on these unigrounded or ungrounded wyes or whatever you want to call them.

There is one exception though. For a 3 pot Wye/Delta bank the lower rated pots will work where the neutral is "floated". I have seen just a few spans apart in the same circuit, banks with the same secondary voltage with the first bank hooked Wye/Delta and the second bank hooked Delta/Delta. Of course the labels on the first bank said. 7200/12470 and on the second bank. 12000/20800. For 2 pot banks, single pots and Wye secondaries you are going to have to use the 20.8 pots.

in theory it can be done Swimpy but like 'door says alot of times the pots won't hold it...

I've seen it go both ways... the other thing about the labels some folks don't get 7200/12470 phase to dirt 7.2 is wye hook up 12470 is delta hook up...

heres a pretty cool link for ya to ummmm "brush up"

http://insayne_kokane.tripod.com/transformers.shtml

damn it man I just learned to google! this kicks ASS!!!

for what it's worth...

Edge

MAKE SURE YOU READ THE DISCLAIMER AT THE TOP OF THE LINK SWAMP!!!:D

[MI-Lineman]

Ya'll young punks...In the "New Linework"...just got it ALL FIGURED out don't ya.:D

Carry on Mike. YOU and, the new "Linemen" that are comin into the trade...

"Sign the Disclamer".....
You guys are...the "New linemen". Sad.:(

WELL YA MUST HAVE ACTUALLY LOOKED AT EDGE'S LINK! BOUT TIME YA STARTED READING PEOPLES POSTS!

SO YOU SAYIN THE "NEW BREED OF LINEMAN" IS MORE TECHNICAL? I DON'T GET WHAT YA MEAN? I DON'T REALLY THINK DOOR AND EDGE ARE EXACTLY "NEW BREED?" AND THEY'RE THE ONES COMIN UP WITH THIS GOOD STUFF!!!

NO OFFENSE GUYS!!!:D

I THINK GREG, YOU WERE JUST A "PARTS CHANGER?" DIDN'T KNOW WHY YA DID WHAT YOU DID AND IN YOUR OWN WORDS "DIDN'T CARE!":eek:

[Edge]

No what I was pointing out was the statement that 4160 was always delta. The statement needs to be revised, Did anyone else catch it???

yeah Steve I think they kinda cya'd with the "this is by no means a complete list" line... but you're right it is kinda ambiguous...

for what it's worth...

Edge

[topgroove]

here in WNY 4160 has always been wye. the point to remember is any polyphase voltage can be wye or delta