Connections at the transformer???

[tdkkart]

Something I've seen and questioned more than once, and was reminded again today when I took the dog on our daily trek to the mailbox.

In our development, each pair of houses are fed underground from 1 poletop transformer. At the top of each pole the wires come out of the conduit and are spliced in pairs, along with the pigtail that goes to the transformer taps.

My issue is the pigtails. We have 3 pairs of service wires which I assume are each at least 2/0, being fed by pigtails spliced to each pair. Each pigtail is not anywhere near as large as even a single 2/0 cable, let alone a pair of cables.

How do they get away with this??
Seems like a fuse link to me??
(each xsfmr is fused on the input side)

 

[tfi racing]

Simple.The utility doesn't follow the same code rules the rest of us do,and the free air ampacity is much greater than that of a conductors in conduit or cable.For example CEC Table 3,Al conductors in free air,allows 300A on 4/0,
Table 4,Al conductors in conduit or cable the ampacity is 185A(allowed to be used for 200A in residential services BTW).The secondary(wires to your house)is NOT switched nor fused at the pole,that is why the length of the conductors from your meter to the service disconnect is restricted.

 

[Aceman]

How do they get away with this??
Seems like a fuse link to me??

Because they can. I have faith in the power company, they've been doing it a long time and I don't see too many transformer connections burning up, so they must have an idea of what works and what doesn't.

 

[mrb]

the conductors are in free air and have a high temp rating. They have to use larger wire in the conduit due to heat buildup but it still smaller than what we would have to use for an installation under NEC.

 

[shamrock12]

These guys are correct. Conductors in free air can handle more load because heat disperse better than inside a conduit. Also most households usually draw far less than 100 amps continuously all day.

 

[Mellotron]

Don't go on a honeymoon with your power company just yet. I called my power company and told them I was thinking about adding a small shop and house addition and I wanted advice on power. They sent out a guy (which was nice of them) and the first thing he did was peer up at my pole transformer and then he amusingly snickered. It's one of those deals where you can read the guy like a book and he knew some sort of industry inside joke.. All I did was say hi, I didn't even tell him what I wanted to do yet. So he immediately says "So do you get alot of brown-outs and fluctuations?" And I'm like "Uhhh now that you mention it......YES!" He said my wiring from the transformer to the house is "a little small". So basically he tries to sell me a replacement bigger pole transformer and pulling a new bigger set of wire (since it's in conduit). If I recall the estimate was about $3500.00 which included a couple hundred bucks for the old transformer. I said thanks but no thanks for now. He never mentioned what gauge wire I had or what it should be nor did he mention what replacement transformer I would get. He prolly thought that's just too complex for a silly customer.

I currently have a 25kva pole pig that only feeds me. My panel is 200 amps.

I read somewhere online a few years ago that 25kva is only about 180 amps or something. Me and math don't get along. You guys might know more.

Moral of the story is I believe lots of homes are setup with the cheap bare minimums simply because not everybody is pulling major amps all the time.

Unfortunately I'm in a rural area with only electricity running everything. My electric furnace alone pulls 60+ amps. You would think they would beef things up a bit on the poles. Again it's all about saving $$$$$ and upselling the customer I suppose.

 

[shamrock12]

By my calculation, a 25KVA transformer at 240V would have max. ampacity of 104. No wonder he was snickering.

 

[Mellotron]

By my calculation, a 25KVA transformer at 240V would have max. ampacity of 104. No wonder he was snickering.

Heh! See. I rest my case

Maybe lightning will hit mine.

 

[walrus]

Is the transformer on the pole?? Why should you pay to change it if so, its theirs not yours. Does the wire from the Transformer go over head? If so its theirs also

 

[mmg440]

Is the transformer on the pole?? Why should you pay to change it if so, its theirs not yours. Does the wire from the Transformer go over head? If so its theirs also

I would think they are asking him to pay for the upgrade because his service is a working service. If the transformer has its last days on the poll and it needs to be replaced due to failer from (overheating, lighting or most anything except a bullet-- the bullet would have to police out most likley) they would most likely upgrade instead of just replacing it at that point. Just, my opinion from what I have heard about and seen happen.

 

[porschedude996TT]

I just don't get these power companies and the way they work. Has anyone looked at their power bill in the last decade? I get slammed for 0-100% of "Life-Line Rate", 101-200% above "Life-Line Rate", 201-300% above "Life-Line Rate", Transmission Tax, BS Tax, Moon Tax "In case the Moon doesn’t come up", Sun Tax, "In case the Sun doesn't come up" and a bunch of other BS. And who is this Life-Line Person, my freezer takes as much power to put me over the BS 100% Life-Line value.

I am working on upgrading my service and I have a 3" underground conduit that was put in 20 years ago. The current house panel is 100amp/240v. The conductors are only good to 125amp/240v. I wanted to upgrade to 200amp/240v and they wanted me to dig up the existing 3" conduit to go to a 4" conduit. I asked the project engineer if we could use copper to reduce the size of three conductors he said they don't use copper. I said how about you remove your alum wire and I pull my own copper 40-50' in the 3" and they you connect in the existing ground box. He said no, I could divert the existing 3" conduit to a new ground box next to the existing ground box and he could feed alum. wire to my copper in a 4" conduit between the two boxes. Now with that said and let’s say the whole thing is done, the power company is still responsible for the equipment, wire, conduit, and connectors all the way to the bottom of my electric meter. What a Goat-Rope this is. I decided to reduce my plans to a 125amp service, which is an upgrade to my existing 100amp panel. Net result is I can put a 100amp breaker in the 125amp panel and feed my new shop. No impact to the existing house since there is are no 220 circuits, no electric heat, or elect water heater

Sorry for the High-Jacking, just pisses my off on the utilities get away with as much as they do. I don't understand if you wanted to increase to a larger supply and they are going to sell you more electricity that they wouldn't put in a larger what-ever-it-takes device to sell you the power?... Do I have to pay for a bigger hose or pump when I get a car with a bigger gas tank? I know this over simplifies the subject, but WTF...

 

[tdkkart]

What the power company will/won't supply seems to vary widely with the region and the company. Around here, if you can show a genuine need for X amount of power the power company will provide it, up to the meter socket, from there it's your problem.

Our billing is crazy also, rather than simply charging a set rate/kw, they average everything down to a daily useage using some funky multiplier and then multiply by the number of days. The problem is the multipliers change. It all comes out in the end, but it's very confusing to read and figure out.

The issue I'm having right now is that I have 2 meters on my property, one on the house, one on the shop. The house gets charged the "residential" rate of $.08/kw, the shop gets charged the "business" rate of $.12/kw.
When I ask about the difference, their answer is that they "assume" that a 2nd meter means that I'm running a business. Makes no difference if I actually am running a business or not, since they assume it, that's what I get charged. They sent a guy out to make sure I didn't have a shingle over the door etc, still getting charged the same rate.
The previous owner built the shop, put it on a seperate meter simply because of the shape of the lot, location of the powerlines, landscaping etc it was closer/easier/cheaper to get the power to the shop on it's own line rather than run it off the house. It just costs 50% more for the power this way.

 

[shamrock12]

In my area, property owner are responsible for everything until it reach the pole then that is where the utility responsibility meet. Meter box, conduits, cables all must be supplied and installed at owner's responsibility. Utility will supply and install the meter after everything pass inspection. Utility is responsible for the transformer and they will make the connections.

porschedude, I believe that 3" conduit should be sufficient for 4/0 al. quad. The distance doesn't sounds much, but as long as the conduit run is fairly straightforward and not exceeding 360 degree bends (the less the better), the pull should not be too difficult. I think the poco did not want to break a sweat by using a 4" conduit to pull through. The oversized conduit could be local poco requirement but it sounds like a BS to me.

 

[rinny_tin_tin]

Something I've seen and questioned more than once, and was reminded again today when I took the dog on our daily trek to the mailbox.

In our development, each pair of houses are fed underground from 1 poletop transformer. At the top of each pole the wires come out of the conduit and are spliced in pairs, along with the pigtail that goes to the transformer taps.

My issue is the pigtails. We have 3 pairs of service wires which I assume are each at least 2/0, being fed by pigtails spliced to each pair. Each pigtail is not anywhere near as large as even a single 2/0 cable, let alone a pair of cables.

How do they get away with this??
Seems like a fuse link to me??
(each xsfmr is fused on the input side)

Its hard to picture the circumstances with words - but I'll throw this out - are you sure the wires you are looking at are not the incoming wires to the transformer primary - in which case would be much higher voltage - perhaps 13.2 kV and thus less amps?

 

[porschedude996TT]

In my area, property owner are responsible for everything until it reach the pole then that is where the utility responsibility meet. Meter box, conduits, cables all must be supplied and installed at owner's responsibility. Utility will supply and install the meter after everything pass inspection. Utility is responsible for the transformer and they will make the connections.

porschedude, I believe that 3" conduit should be sufficient for 4/0 al. quad. The distance doesn't sounds much, but as long as the conduit run is fairly straightforward and not exceeding 360 degree bends (the less the better), the pull should not be too difficult. I think the poco did not want to break a sweat by using a 4" conduit to pull through. The oversized conduit could be local poco requirement but it sounds like a BS to me.

I agree that 3" is big enough, but PGE wants 4". I was helping my Brothern-Law on his house, he is a General Contrator and has built houses and barns and office buildings and remodels that would knock your socks off, and at the begining of the house build (three years prior) he put in 3" x 50' in the foundation wall toward where the direct bury cable was laid out 20 years ago. They would not agree to pull his service of any size thru the 3". We ended up digging it up, framing a small pop-out to the side of the house to put meter/panel under the 4" that could not be easily placed in the foundation concrete.

We used the same NEC tables you use and the PGE uses something different (Their Own Doc). The copper in the 3" was my attemt to get around the 4". Understand the airspace and the number of 90 degree turns when pulling wire, they (PGE) want the wire to fall into the hole and carry itself into the box???

 

[MisterCMK]

they (PGE) want the wire to fall into the hole and carry itself into the box???

Don't we all?

 

[Mellotron]

Well then. This sheds light on power company behavior. Explains alot.
http://www.diychatroom.com/f18/pole-transfomer-size-question-24501/

Hehee! Makes me wanna run the sucker at 200% for giggles!

 

[walrus]

We used the same NEC tables you use and the PGE uses something different (Their Own Doc). The copper in the 3" was my attemt to get around the 4". Understand the airspace and the number of 90 degree turns when pulling wire, they (PGE) want the wire to fall into the hole and carry itself into the box???

Electric utilities don't fall under the NEC. Get a handbook from the utility before you start to see what they want and accept

 

[malibu101]

As I have heard and cannot cite any sources. Power companies are regulated, in many ways, by the PUC (public utilities commision). The PUC says that power companies must mantain a reliable distribution system.
As long as your house has "quality" power without losing power due to power company problems (obviously acts of nature don't count) they are upholding their end of the bargain.
Power companies, as was said above, all have their own wants for what, and how, they will provide power. My Power company has everything online on what they require from overhead drops to underground to high voltage services for large buildings.

 

[rinny_tin_tin]

Electric utilities don't fall under the NEC. Get a handbook from the utility before you start to see what they want and accept

In general, the utilities follow the NESC - however, which edition is another thing.

 

[burleymike]

I know what you guys mean about undersized conductors feeding the house. I upgraded to 200 amp servce a couple years ago. The lineman came out and connectied the existing wires from the transformer to my new mast.

It is hard to tell what the gauge is from the ground but it looks like probably #4. When the 15kw heat, dryer, and water are all running the lights do dim a little. At least I don't have to worry about snow building up on the wires from the pole.

They do sometimes way undersize the wires. The building across the road from us a really small wire from the transformer to the mast. One night I could see something glowing over there, then flames. After the fire department came and watched the insulation burn off the wire a lineman showed up and replaced the wire with much heavier wire.

I live close enough to the city that they provide my power. It was super easy to upgrade my service. I just went to city hall and asked for a permit. The lady laughed at me and said nobody gets permits. I asked even for a service upgrade? She said "for that one you better get a permit."

I put up the new meter box and mast right next to the old one and then called the inspector. He covers hundreds of miles and could not come out that day so he said he would be there tomorrow. The next afternoon he came out looked at everything and signed the little sticker on the box and my permit.

Then I called the city lineman and he came out and switched the wires to the new box.

When I lived in Oregon and did the service on my old house PGE (portland general) was a pain to deal with.

 

[Mellotron]

When you do this they will upgrade your service drop.

Holy **** I should hope so! Scary.

 

[rcleaver]

I asked the utility for new service to my property in NE PA. They quoted about $12,000 and I have to dig the trench. Part of the problem is that my property is more than a mie from the pole.

I told them to forget it and I'm considering being off the grid, especially because I will have access to natural gas below the property.

 

[sberry]

They installed a 15Kva on my 400A service. I bargained with them on wire size, the lineman up sized the conductors.

 

[Mellotron]

They installed a 15Kva on my 400A service. I bargained with them on wire size, the lineman up sized the conductors.

15Kva on 400A? Wow I dont feel so bad now. At least your wiring is better. Think you might kill that transformer eventually?

 

[ironman2424]

go outside and shoot the heck out of it with a shotgun and tell em you need it fixed. you don't have a clue what could have happened. tear it up enough and they will have to replace it all with new stuff. rent a generator for a few days . problem solved.

 

[ironman2424]

mellotron you would have to agree lol Right?

 

[mmg440]

go outside and shoot the heck out of it with a shotgun and tell em you need it fixed. you don't have a clue what could have happened. tear it up enough and they will have to replace it all with new stuff. rent a generator for a few days . problem solved.

Hope nobody sees you do it and reports you or puts it up on you tube. I think it might draw a little attention even in a somewhat remote area. I know repaeted shot gun fire makes me turn my head. Don't forget the tranformer may burst if internally shorted. If something of this sort was done don't forget to shut down and unplug your computer and **** so any surges that come threw the line won't damage anything else.

 

[nadogail]

A lot of what the Electric Utility gets blamed for in this string of postings is beyond their control. They, the utilities in general, are regulated by various Public Utility Comissions which vary from stste to state.

Also the enviorenmentalists (sp?) and the courts get involved.

 

[A_Pmech]

A 15 pot on a 400A service?

Man, you guys have some tough power companies. I ran my business and house on a 50A farm service for ten years before I got around to upgrading everything. I was sagging the service wires to the pole, so I figured it was time.

The local electric cooperative was incredibly helpful. I'm in a rural area, so single phase is the order of the day, unless I want to pay $7,000 a mile for three miles to get the other conductors in. They set me up with a 400A 240V service, upgradable to 400A 600V, which I'd then step down and isolate to 240V. (All my service conduit is now under concrete.)

I explained that I didn't want primary power on my property's overhead because of cranes, trucks, forklifts, etc that run underneath it. They said "no problem!" and paralleled in a bunch of 1/0 to handle the load.

They hung a 37.5 on the pole "to get me started" and said as I add load to give them a call. "We'd rather swap it to a 100kva than have you blow a pot on the weekend."

When they installed the service, it took 4-5 guys and trucks all day plus overtime to take down all my old service, replace the pole, pull in all the big wire, and hang all the new stuff.

The best part? It was all free!

Oh... They said if my power demand rises enough, they'll "force" me to go to three-phase. But... They would not charge me the $7,000 a mile to install the conductor. I like these guys!

 

[Mellotron]

mellotron you would have to agree lol Right?

HAHA! Yep I think they would definitely get me new stuff on the pole after doing that! Now where did I put my Double X 12 Gauge Rounds at.....

 

[Mellotron]

A 15 pot on a 400A service?

Man, you guys have some tough power companies. I ran my business and house on a 50A farm service for ten years before I got around to upgrading everything. I was sagging the service wires to the pole, so I figured it was time.

The local electric cooperative was incredibly helpful. I'm in a rural area, so single phase is the order of the day, unless I want to pay $7,000 a mile for three miles to get the other conductors in. They set me up with a 400A 240V service, upgradable to 400A 600V, which I'd then step down and isolate to 240V. (All my service conduit is now under concrete.)

I explained that I didn't want primary power on my property's overhead because of cranes, trucks, forklifts, etc that run underneath it. They said "no problem!" and paralleled in a bunch of 1/0 to handle the load.

They hung a 37.5 on the pole "to get me started" and said as I add load to give them a call. "We'd rather swap it to a 100kva than have you blow a pot on the weekend."

When they installed the service, it took 4-5 guys and trucks all day plus overtime to take down all my old service, replace the pole, pull in all the big wire, and hang all the new stuff.

The best part? It was all free!

Oh... They said if my power demand rises enough, they'll "force" me to go to three-phase. But... They would not charge me the $7,000 a mile to install the conductor. I like these guys!

WOW! You are very lucky! They seem so gracious and helpful, I'm amazed they just didn't bolt up a 100Kva and be done with it.

 

[2LTim]

With a Co-op, you are one of the owners, ie: their boss. You bet they will take care of you. With all of the poco's I have delt with in Iowa, they are responcible for any "Ovehead Service and Conductors." When you want it dropped in the ground, it becomes your baby. This includes the 15kv primary wire to "Their" transformer if your total secondary loop totals more than 200'. The installed price for this was about $9 per foot, 10 years ago when I had mine installed.