Surging lights

[rcdallas]

Here's one I had today; check voltage at a single phase customer getting 124/158 and 248 phase to phase being served by 2 pot bank.

Made my head scratch...actuality quite simple. What was the problem?

[johnbellamy]

Here's one I had today; check voltage at a single phase customer getting 124/158 and 248 phase to phase being served by 2 pot bank.

Made my head scratch...actuality quite simple. What was the problem?

Open secondary neutral.

[loodvig]

What do you mean by 'a two pot bank'?
Two pots making three phase secondary?

[rcdallas]

Wasn't a neutral problem.

What I mean is the customer was fed from a open wye open delta 120/240 bank. The customer only had single phase service...another customer was being fed 3 phase service off this bank.

Here's another clue, when I went and checked voltage on the secondary next to the bank I was getting 124/124/248 at the connectors feeding the single phase customer.

[johnbellamy]

What do you mean by 'a two pot bank'?
Two pots making three phase secondary?

He is talking about an open delta 120/240/208.

Pretty common around these parts, feeds houses and maybe some pump, or some business or shop that needs 3 phase for motors.

He does not say if all were having trouble off this bank, or just the one customer?

So the house would be your standard 120/240 V 200 or 400 amp single phase service being fed from the open bank.

We will see what his answer is.

[wtdoor67]

Split bolt connector gone bad. I would have guessed neutral first also.

[rcdallas]

Before I checked voltage next to the bank, I walked over to a three phase customer and checked voltage at the meter base and was getting

124/124/178 -- 248/248/248

[johnbellamy]

Bad pot, or an open line fuse.

[rcdallas]

Like I said I was scratching my head looking at this old school built bank...

Here's a diagram of how the bank was built. Old shit.

[johnbellamy]

I am gonna stop playin, you goofy bastards, why don't ya post some pics before hand, or give your scenerios a little more detail, how many people have seen a Y open delta built like that.

Ya said your bank was good. **** it, back to the wood shed.

[rcdallas]

Yeah I hear ya John...I was just giving it the way I walked into it. I had just left the chiropractors office and I wasn't in the mood to deal with this as my neck was killing me. I first check voltage at 1ph meterbase seen that, walked over to the 3ph customer and see the low voltage on the power leg, then I went up in the bucket and checked it at the secondary and was getting good voltage.

I called another guy that's been here 30 years after that. He shows up 15 minutes later and we both check voltage at the 1ph customer again and was getting good voltage and we both walked back to the 3ph customer and was getting good voltage.

The connection was hot when I first got there then it cooled down by the time I first checked voltage at the secondary. I was like WTF ?

Crazy shit fo sho...all in all pretty simple.

We don't build banks like that anymore with the tie bus going thru the secondary.

[johnbellamy]

Good to see, I will put it in the memory bank, and will keep an eye out something built like it.

It is always easy to over look something obivious, especially when you had the readings you did on the single phase service, or just look up an see a 2 pot bank, know how you wire it, and assume it is built to standard.

But certain problems automaticaly trigger certain mind sets, sometimes ya get caught, knock yourself up side your head and say how the hell did I miss that. Only good thing about workin by yourself is ya gotta buy for yourself, not for the whole crew.

[loodvig]

Somebody, I forget who, told me once that is a Scott hook up? I dunno I can't find my old GE transformer book.

[wtdoor67]

Had a guy tell me once he had a problem with dimming lights. The primary was 4 KV. Said he went to the sub and couldn't find anything wrong. Eventually drove out the primary and said a large tree limb was touching the primary off and on as the wind blew. Cut the limb away and that cured it. A trouble person should keep a diary. Probably would be interesting later on.

Went once on a deal after the regular guy swore he couldn't find anything wrong. It was a 2 pot bank on 34.5 and the rural customer had normal power to his house and a 3 phase motor in his shop. The three phase to his motor was where he was having low voltage on one leg. Went straight to the weatherhead and checked voltage on either side of the connector. Normal on the source side and low on the load side. Replaced the connector and it was alright. Took about 20 minutes. Sometimes it's the simple stuff.

[MI-Lineman]

We use the hell outta those banks! DTE really uses the sh!t outta them though!! Except their lighter pots on one street and the power tubs 2 blocks away over a fence behind a garage in a rear lot line?:o Fun!:)

As far as the "open neutral" theory on a single phase customer I guess I wouldn't think that? If it was truly open usually ya get one side higher than hell and the other bottomed out! I've seen 0-240 on one IF it was completely open! Usually when it's a neutral connection goin bad or a urd neutral goin bad it's around 100-140 or some where about? That imbalance thingy!!;)

Those dam split bolts!! Course beats those dam squeeze ons!!:D Get way to many of those goin bad!

[johnbellamy]

I should have said loose or open neutral, but that being said surging lights, or any kind of stray voltage usually means a neutral problem, and this was not a split bank, and i have been on plenty of loose or open neutrals where the voltage shows good with a volt meter until load is applied, a BEAST is a great tool for any odd or stray voltage detection.

Just clarifying, not disagreeing with you.

[MI-Lineman]

I should have said loose or open neutral, but that being said surging lights, or any kind of stray voltage usually means a neutral problem, and this was not a split bank, and i have been on plenty of loose or open neutrals where the voltage shows good with a volt meter until load is applied, a BEAST is a great tool for any odd or stray voltage detection.

Just clarifying, not disagreeing with you.

No you're exactly right!! The BEAST is a good device but then there's the MEGA BEAST!!!:cool: My favorite!!:D Except at times it works to good!! Drive me crazy tryin to figure out a 10v swing with all 80a on it??:rolleyes:

Ever gett'em where the "neighbors" srvc has a neutral problem and is starvin the complainer's srvc for one? Those where fun till I figured them out the first time! Now that's the first thing I look for!

[Lineman North Florida]

We use the hell outta those banks! DTE really uses the sh!t outta them though!! Except their lighter pots on one street and the power tubs 2 blocks away over a fence behind a garage in a rear lot line?:o Fun!:)

As far as the "open neutral" theory on a single phase customer I guess I wouldn't think that? If it was truly open usually ya get one side higher than hell and the other bottomed out! I've seen 0-240 on one IF it was completely open! Usually when it's a neutral connection goin bad or a urd neutral goin bad it's around 100-140 or some where about? That imbalance thingy!!;)

Those dam split bolts!! Course beats those dam squeeze ons!!:D Get way to many of those goin bad!I've seen a few old banks built with the tie legs through the open wire secondaries but I have never seen them built with a lighting pot on one pole and power pot on another and I am thankful as it sounds like a deathtrap to me.

[Lineman North Florida]

Like I said I was scratching my head looking at this old school built bank...

Here's a diagram of how the bank was built. Old shit.I've seen the banking of additive and subtractive pots get some guys before around here, not paying close attention to how the secondaries are hooked up when you have a bad pot and one of them is sub and going back with additive= some high voltage on the kitty leg:D

[Pootnaigle]

Went on an ice storm up near dallas once. all the alleys were paved and every pole had a pot on it. Had to look twice as there were several 3 phase customers but only one pot per pole.Open wire secondary on racks running thru the alleys. Needless to say they built a 3 pot bank using one pot per pole and the secondary as a buss. Also saw 3 transformers all tied thru the secondary so if one blew the others would pick up the load .It seemed to me then and still does that this is a death trap if they ever built one. I was damn glad to leave that nightmare. I sure would never wanna troubleshoot a system like that.

[rcdallas]

One thing they did do right in Dallas is their phasing is consistent throughout the system, all square corners and I believe it's something like A phase is always N or W...something like that I've been told.

Come out to the old TPL or Tessco parts of the system and it's whatever works. :rolleyes:

[MI-Lineman]

I've seen a few old banks built with the tie legs through the open wire secondaries but I have never seen them built with a lighting pot on one pole and power pot on another and I am thankful as it sounds like a deathtrap to me.

I wouldn't call it a death trap? Yeah the 4 wire secondary is pretty much (as well as the primary!) banked which some think is a death trap but I actually enjoyed it! I worked with a few hands from Florida and they got acclimated pretty quick! One was called "Gator?" He was good to work with? I forget the other one but I'm sure he's retired? Nice old boy but didn't like climbin much? He was more of a sub guy but really smart!

Sorry Ran....Oops I mean RC! Seems I hijacked your thread?;)

[MI-Lineman]

One thing they did do right in Dallas is their phasing is consistent throughout the system, all square corners and I believe it's something like A phase is always N or W...something like that I've been told.

Come out to the old TPL or Tessco parts of the system and it's whatever works. :rolleyes:

"A" or "X" to us Yanks I guess is usually North and West yes! As for DTE it's what we called "bastard corners!" A phasin set is you're best friend of course!!!!:cool:

[Lineman North Florida]

Went on an ice storm up near dallas once. all the alleys were paved and every pole had a pot on it. Had to look twice as there were several 3 phase customers but only one pot per pole.Open wire secondary on racks running thru the alleys. Needless to say they built a 3 pot bank using one pot per pole and the secondary as a buss. Also saw 3 transformers all tied thru the secondary so if one blew the others would pick up the load .It seemed to me then and still does that this is a death trap if they ever built one. I was damn glad to leave that nightmare. I sure would never wanna troubleshoot a system like that.I've seen pots tied in series on the secondaries and never could see where that was a good idea either, kinda like johnny balls in open wire, why not just double deadend them on the pole instead. I've worked on FPL property down in Miami years ago and it was full of these kind of things, oh and grasshopper cutouts.:D

[Lineman North Florida]

I wouldn't call it a death trap? Yeah the 4 wire secondary is pretty much (as well as the primary!) banked which some think is a death trap but I actually enjoyed it! I worked with a few hands from Florida and they got acclimated pretty quick! One was called "Gator?" He was good to work with? I forget the other one but I'm sure he's retired? Nice old boy but didn't like climbin much? He was more of a sub guy but really smart!

Sorry Ran....Oops I mean RC! Seems I hijacked your thread?;) I guess it's all what you become accustomed to, I guess I've gotten kind of spoiled in that we have some good standards where I'm at ie all standard primary phasing A phase top South or East, banks all built on the same pole etc etc, I used to like seeing all the different things, now not so much, guess it means I'm getting old.:D

[slimdalineman]

We use the hell outta those banks! DTE really uses the sh!t outta them though!! Except their lighter pots on one street and the power tubs 2 blocks away over a fence behind a garage in a rear lot line?:o Fun!:)

As far as the "open neutral" theory on a single phase customer I guess I wouldn't think that? If it was truly open usually ya get one side higher than hell and the other bottomed out! I've seen 0-240 on one IF it was completely open! Usually when it's a neutral connection goin bad or a urd neutral goin bad it's around 100-140 or some where about? That imbalance thingy!!;)

Those dam split bolts!! Course beats those dam squeeze ons!!:D Get way to many of those goin bad!

in rural sections you'll see higher difference when losing the nuetral but in urban areas its very common to not see as drastic of a difference seeing (around here at least) mains get ground through the water pipes...hell alot of folks probably dont have a good nuetral connection and dont know no better.

[slimdalineman]

I should have said loose or open neutral, but that being said surging lights, or any kind of stray voltage usually means a neutral problem, and this was not a split bank, and i have been on plenty of loose or open neutrals where the voltage shows good with a volt meter until load is applied, a BEAST is a great tool for any odd or stray voltage detection.

Just clarifying, not disagreeing with you.

the Beast does work great but alot of us carry a hair dryer on our trucks so we dont have to run to the garage to get the beast....works just as well for identifying nuetral problems

[johnbellamy]

the Beast does work great but alot of us carry a hair dryer on our trucks so we dont have to run to the garage to get the beast....works just as well for identifying nuetral problems

Luckly we have a beast on all of our trouble trucks, some have the Big Beast.

I know it is different in alot of places still , but if we were to take the cover plate of a main, or even the low part of a meter base on the load side of the meter and an incidental falsh would accure, the we would be liable to repair or replace any damage, plus a hell of alot of paper work, peer review, and even disipline could be a result, kinda silly, but reality.

It is crazy but you have to change your mind set these days, no where the boundries are, and if you cross them, even trying to help a customer out, all intentions are good, you risk a huge headache, and depending on what happens, it could count as a strike against you or a letter in your file that can lead to your termination.

But if you are just plugging it into a socket, in different areas in the house, under different breakers and it does not work anywhere I guess that might work too?

Maybe you can fill us in on how ya do it, it might be something alot of guys might use if they work for a place that only buys just one for everybody to use, cause I know there are plenty of places out there like that.

[Pootnaigle]

Ummmmmm a quick way to look without risking anythang is to use a ampmeter at the groundrod. any reading other than zero tells ya they have a prollem.

[MI-Lineman]

in rural sections you'll see higher difference when losing the nuetral but in urban areas its very common to not see as drastic of a difference seeing (around here at least) mains get ground through the water pipes...hell alot of folks probably dont have a good nuetral connection and dont know no better.

Well yeah cause ya got more ground rods with more buildings? Makes sense but I've never really seen that here? Usually we get a bright/dim only after the customer looses their grounds. Like you say they don't know it for some time!

Had one I never figured out? A trailer was complainin in a rural area so I hook up the Mega Beast and they had a 30v swing? Their hot water and dryer wouldn't kick on for 3 weeks before they figured it was on our end? 3 WEEKS WITH NO HOT WATER OR CLOSE DRYER????:eek:

Anyway we changed every connection, replaced 8' of copper missin on the pole ground:rolleyes:, changed the tub and still had the swing?? So gettin close to quittin time we checked a few other houses on the line which was towards the end of the circuit and found the same swing? There were two sets of regs on neutral also but I didn't think that would do it BUT they were only at 113/113 towards the end at the trnsfrmrs. An app and I found at least 12 automatics in three spans of wire and I figured that must be it? I've had quite a few automatics go bad or burn up in open wire from slappin together and cause bright/dims. So we told dispatch to let the on-call crew know and somehow it got lost and they ended up crankin up the regs only and never checked the trailer to see if it corrected but we've had no call back?

[johnbellamy]

Wasn't a neutral problem.

What I mean is the customer was fed from a open wye open delta 120/240 bank. The customer only had single phase service...another customer was being fed 3 phase service off this bank.

Here's another clue, when I went and checked voltage on the secondary next to the bank I was getting 124/124/248 at the connectors feeding the single phase customer.

You say right here you are getting 124/124/248 at your source, then 124/154/240 at the house. Then you are getting 124/124/178 at you three phase sevice, so explain to me how there is a 30+ volt shift to your 124 leg to the house, and a 30- volt shift to your 208 leg to the three phase service?

[johnbellamy]

If you understand what I am saying, or get the point that if you understood that it is usually a bad connection, or something simple, always check your basics first.

Alot of guys will put in all sorts of senseless efforts into disecting a problem, more time than it would take to just change all connection on the bank and at the WH.

Alot of places do not have a beast or anything other than a volt meter, some have an amp feature on them, but believe it or not, some of those are outlawed at places because they of what class they are, stupid I know.

If you new what was going on with the volt shift then it should have been an easy fix for you, now you have experienced it, it will be a part of your trouble shooting abilities, if you can explain why the bank functioned that way, and why that imbalance was there, and an why it was 30v + or - great.

I see ya got a real passion for understanding banks, hook ups and such, I do not know how long you have been a JL, but take the time, and understand in the field you have to see and trust what is in front of you, and do not let all the classroom linework get in your way.

It is always good to ask for help when you need it, ask questions ect. But maybe a good way for you to approach a situation is for you to work the problem out for yourself, I know if you would have checked you connections you would have found the weak link by yourself, made repairs, and probrably felt pretty good about it. Experience is the best teacher, your own, not somebody elses.

[mnk801]

The ends of the secondary coils are lettered ACBD. You can see on the left hand pot that A and C are together and B and D are together. That makes the coils of the left hand pot in parallel which would give 230 across them. That way it will work with the other 2 pots

[reppy007]

Had a 3 phase lateral some time ago,noticed something looked wrong at the fuse location,asked the headlineman to take a look,which we didnt until weeks later when we had a trouble call at a residence.i dont quite remember the voltage that we found,but do remember the cause.At the fuse location which the circuit was framed 19.9 ,then took off delta,framed 12kv the highest jumper come off the stirup and was now laying on a lower phase.So back at the residence which was being fed by an opened-delta bank,both transformers were feeding off the same phase.The customer never complained about their lights ,they were concerned about their a/c.Never seen a case like that again.