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Posted By: electure Very strange single line diagram? - 03/19/04 12:13 PM
I've never seen a service set up like this one that came in for us to bid.
Is this common in some other part of the country?
Here in Southern CA, it certainly isn't how it's done.


[Linked Image]


[Linked Image]


Have any of you seen something like this??...S
Posted By: ayrton Re: Very strange single line diagram? - 03/19/04 12:35 PM
Unless I am missing something, I don't see anything unusual. Only thing I would do different is runn paralell 250's instead of 600's

[This message has been edited by ayrton (edited 03-19-2004).]
Posted By: Yoopersup Re: Very strange single line diagram? - 03/19/04 12:58 PM
They use that in our area . The 1 1/4 is for utility company metering wires. They put the ct's at the transfomer,you then run straight to the main service panel with your service conductors from the transformor. This is only used on larger services.
Posted By: Roger Re: Very strange single line diagram? - 03/19/04 01:17 PM
Hello Electure, I agree with the others, this a common installation (design) here also.

Roger
Posted By: watthead Re: Very strange single line diagram? - 03/19/04 01:27 PM
Where do you guys get that 4-1/2" conduit? Do your supply houses stock it or is it special order? [Linked Image]
Posted By: Roger Re: Very strange single line diagram? - 03/19/04 01:56 PM
Hmmmm, I didn't pay attention to that. [Linked Image]

Come to think of it, with a conflict between the notes and reality, it's actualy a more common design than I first thought. [Linked Image]

Roger

[This message has been edited by Roger (edited 03-19-2004).]
Posted By: Anonymous Re: Very strange single line diagram? - 03/19/04 02:43 PM
Is your question about the metering set up? I see this on "canned" drawings where the E.E. is from a different state and the job is for a nation wide chain type store. So then the question becomes - How do I bid this and stay competitive? Include the C.T. can, C.T.'s labor etc. or not? I have bid this type of set up per drawings with an adder to meet local requirements.
Posted By: Megawatt Re: Very strange single line diagram? - 03/19/04 04:13 PM
Most often the POCO will furnish the 13 terminal Meterbase for the CT installation, you would just have to mount it on some 2" Rigid & Strut. As for the conduit, I would also parallel conductors & use a smaller, more common size of conduit. Watch the price of the copper though, it has been going up lately, & could change quickly.
Posted By: earlydean Re: Very strange single line diagram? - 03/19/04 04:42 PM
The POCO will dictate where the metering enclosure is to be mounted. If you have never seen it like that before (me neither) then you need to check with the POCO as to where they accept the CT meter. Out here (New England) we have to purchase and install a separate CT/PT enclosure, usually as part of the main disconnect, then the meter can is remotely mounted outside the building.

4-1/2 inch conduit? I've never run across it before. Maybe it is metric, then rounded off?
Posted By: iwire Re: Very strange single line diagram? - 03/19/04 09:24 PM
The 4 1/2" conduit seems a little strange. [Linked Image]

As earlydean has said in our area the metering CTs would be inside, I tried to get the local POCO go with this setup before due to space limitations in the building, they said they do not want metering at the transformer in case a replacement is needed they won't have to get the metering guys involved with the swap out.

ayrton and Megawatt, this appears to me to be a 1,200 amp service, 3 sets of 600s, assuming copper.

Are you saying you would rather run 5 sets of 250s in place of 3 sets of 600s?

Why?, more time more material.

I would not try or want to use smaller cable 600 kcmil is great in 3 1/2" conduit.

My wild guess is that Note 4 should read.

"4) PROVIDE 3 SETS 4 #600KCMIL-3 1/2" C"

Bob
Posted By: Megawatt Re: Very strange single line diagram? - 03/19/04 10:54 PM
I was thinking of the availability of the material. 250 is pretty common, & if the pulls are short there wouldn't be a considerable ammount of extra labor...as for the metering setup. The POCO here places the CT's right over the secondary spades in the Padmount, & I've changed out transformers before without involving the Metering Dept. You simply unbolt all of your paddles, and slide the CT's over the paddles, & down the conductor. Works great, & is really quick !
Posted By: iwire Re: Very strange single line diagram? - 03/19/04 11:40 PM
Quote
I've changed out transformers before without involving the Metering Dept. You simply unbolt all of your paddles, and slide the CT's over the paddles, & down the conductor. Works great, & is really quick !

I agree [Linked Image] and I tried to get our local POCO to see it that way too, but they did not want to budge.

I do know it is not the same all over. [Linked Image]

Bob
Posted By: electure Re: Very strange single line diagram? - 03/20/04 01:14 AM
Boy, we're worlds apart!! !! !!, but I figured it must be a Back East kind of thing. (The plans came from GA)
Do your meter bases mount right on the transformer, or do they mount on pedestals?? (Lame Californian)

Here the contractor supplies the primary and secondary conduits, installed (including concrete encasement if more than 2 conduits in parallel) Also, we're responsible for the transformer pad, bedded in gravel, and grounding (2 rods and a length of conductor coming up through the window in the bottom of the pad) for the transformer.
This then becomes the POCO's property.

All specifications for duct sizes, numbers, routing will be determined by the POCO.
(Although I haven't seen 4-1/2" [Linked Image] used, they'll want 4" or 5")

The secondaries will run to a utility pull section mounted on the side of the service.

From there, they'll run to a section that will contain the meters, CTs, and be bussed to a main C/B or fusible switch, probably in the same section as the metering (with a barrier between).

The POCO will supply and install the transformer and cable.

The "coordinate with power company prior to bid" is pretty funny. The POCO people barely have enough time for the people that are doing jobs, much less everybody that's even bidding one...S
Posted By: nesparky Re: Very strange single line diagram? - 03/20/04 03:00 AM
Have seen this more often lately on plans around here. I guess some lazy engineering type are using a canned drawing instead of doing thier job of design for EACH project.
I just look up our POCO's spec book to see how they want the service set up. In this area,the EC is responsible for the primary conduit, transformer pad per the POCO's drawings, the secondary conduit and wire and a CT can properly sized, also the installation of the meter socket and CT's. We also do all the grounding.
By the way that triangle ground grid frequently fails testing in some of our soils. It has been the subject of some very intense discussions about ground resistance specifications and who is going to pay for the fix.
The 4 1/2" conduit would become 4" with an alternate for 5" in my proposal.
Posted By: electure Re: Very strange single line diagram? - 03/20/04 05:08 AM
I also took a picture of the ground detail. 3 rods and a loop of 4/0. Very different than we do it.
I'll put it up. Tomorrow.
Posted By: electure Re: Very strange single line diagram? - 03/20/04 02:58 PM
[Linked Image]

Normally, we'd put in a GEC sized copper Ufer and bond all the "regular" stuff.
If the plans were approved with this 3 rod thing, we'd be required to put it in, too.
Posted By: arseegee Re: Very strange single line diagram? - 03/21/04 01:50 AM
That is a standard CT setup for anything over 600A here in GA. The only thing i see different is we set the CT can away from the xfmr pad (dig the footing and pour it).

GA Power (Southern Company) provides the primaries, transformer, pad, CT can and pedestal. We provide the shovel, sacrete, pipe and secondary conductors.

Company policy is three phase you go to them, and single phase they come to you.
Posted By: Bjarney Re: Very strange single line diagram? - 03/21/04 02:20 AM
Out West, many electric utilities adopt EUSERC service-entrance standards, where generally the utilities provide only components that they install inside metering compartments, but not sockets. [www.euserc.com—looks like ~6 pages of member organizations] In those areas, instead of utility-furnished sockets that are stanchion-mounted by contractors and ‘Grecian urn’ CTs in a padmount transformer, bussed metering bar-CT/PT/meter/test-switch [and cable-pull] sections are provided meeting utility specs.

These days, PDF files on web sites simplify the process.

A few snapshots.. http://www.themeterguy.com/photogallery/freestd400.JPG http://www.themeterguy.com/photogallery/donutctjob.JPG http://www.themeterguy.com/photogallery/donutct2000.JPG http://www.themeterguy.com/photogallery/dnutctswired.JPG http://www.socket-two-me.com/images/vtpacka.jpg http://www.themeterguy.com/photogallery/400ampgear.JPG http://www.themeterguy.com/photogallery/lotsawire.jpg http://www.themeterguy.com/photogallery/servwire.jpg
Posted By: Scott35 Re: Very strange single line diagram? - 03/21/04 07:06 AM
Besides the 4-½" Duct size Note (obviously an error), I have never done (or even seen) any permanent installs with the KWH meter at the PoCo Transformer.

Is this a "Non-California" thing?

As Scott (Electure) knows - along with the other So. Cal. Members here, rarely do we install Secondary Feeders to the PoCo Transformer Vault - or even pole via Riser Ducts.
Anaheim is one area where we do install Secondary Feeders between the PoCo's Transformer Vault / Riser at the Pole, and the Pull Section of the main service / Switch Gear.
Other areas, we just provide Primary and Secondary side Ducts with pull ropes (mandrell ducts too), and the PoCo does the rest.

Also, the Duct requirements are given by the PoCo - as mentioned by Scott (Electure).

Gotta love that GES!!! Quite an elaborate setup, isn't it!

Scott35

p.s. Forgot to mention this also includes purchasing + setting the Transformer Vaults, GES at the Vaults, and all the required stuff for the Primary and Secondary Feeder Ducts per the PoCo's request.
This includes Anaheim also! [Linked Image]

Did some Primary Feeder Underground Ducts on a rather steep hill once. Was really "Fun" putting the Sand and Gravel in for the Cushion! (Fun Read: PITA!!!).

Gluing the Ducts was less fun - trying to keep the can from rolling down the hill became an art form!

Keeping from "Getting High" on the fumes, then rolling down the hill, was a concern too... [Linked Image]

Wasn't around when (if) the Concrete got pumped into the Trench for the Primary Ducts - busy playing around on some other Projects...

Scott35

Returned and edited to add the above stuff.

[This message has been edited by Scott35 (edited 03-21-2004).]
Posted By: Ron Re: Very strange single line diagram? - 03/21/04 04:11 PM
It is possible that the utility wanted to primary meter, hence the location of the meter.
I've never seen a set of service entrance drawings, local or not, that did not require the electrician to coordinate with the Utility Company, and include all related costs.
Nobody knows the local utility requirements better than the local electricians.
Posted By: CTwireman Re: Very strange single line diagram? - 03/24/04 12:00 AM
Correct me if I'm wrong, but running 4/0 to a ground rod seems like a waste.
Posted By: Bjarney Re: Very strange single line diagram? - 03/24/04 02:50 AM
The local Edison “ESR” book is freely available to designers in Georgia 24/7—likely the same for LADWP and other SoCal municipals. www.sce.com/NR/rdonlyres/eksf g5ho...dtt35ipjx6hftqev2h/esr_March_05_2004.pdf

No offense intended to electure, Scott35 and others below the 36th parallel, but here is a truly “Only in Southern California” link… <I can’t resist!> www.sce.com/sc3/008_sales/008d_film_loc/default.htm




[This message has been edited by Bjarney (edited 03-23-2004).]
Posted By: Mean Gene Re: Very strange single line diagram? - 03/24/04 04:53 PM
Bjarney,

The “Only in Southern California” link… was priceless.

I busted a gut when I read "A Location for Any Occasion - Interiors: We've got auditoriums, basements, gyms....even a fully-equipped delicatessen complete with fake food!"
Posted By: Bjarney Re: Very strange single line diagram? - 03/24/04 05:11 PM
Yeah, NorCal is a lot different — We’re a bunch of tree-hugging chai-slurping lumberjack surfers. But, we share a great gastronomic prize with SoCal — sushi!
Posted By: electure Re: Very strange single line diagram? - 03/24/04 06:20 PM
Bjarney,
I'm sure none of us take offense [Linked Image] Thanks for posting it. It's quite good!
I didn't see mention of one of their locations, though. A major league baseball field with their name on it. [Linked Image]
(You mean you guys don't use "fake food" up North?)

[This message has been edited by electure (edited 03-24-2004).]
Posted By: ayrton Re: Very strange single line diagram? - 03/25/04 04:44 PM
When I first read this post, I missed the 3 sets of 600's. Iwire assumes 1200A sevice which is probably correct. What is the service size Electure?? It is hard to base an opinion on what I would do exactly when I don't know the actual service size.
Posted By: Bjarney Re: Very strange single line diagram? - 04/05/04 11:17 PM
 



[This message has been edited by Bjarney (edited 04-05-2004).]
Posted By: electure Re: Very strange single line diagram? - 04/06/04 12:19 AM
1200A 480/277Y

We will have nothing to do with the size of the conductors in the service lateral.
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