This is a service change that for the most part I did with one helper.

The building had a 4000 amp 208/120 service, we changed that to a 3000 amp 480/277 service.

We also added a 1200 480 volt switchgear almost 400' from the new service.

The original service had two 800 amp 208 volt feeders that fed two 208 to 480 volt transformers to feed some 480 volt refrigeration equipment.

My entire "print" for this job was an 8.5" x 11" paper one line diagram drawn by a VP at my office.

Key points.

1)Install new pad mount transformer outside and run conduit to a POCO substation.

2)Install new 480 volt 3000 amp switchgear

3)Refeed existing 4000 amp 208 service gear with 1000 KVA transformer

4)Run two 300 amp 480 volt feeds for refrigeration equipment.

5)Run 1200 480 volt feeder and install switch gear on the other side of building.

6)Reroute Fire pump feeder off of 4000 amp service gear and to another 208 service in the same area.

7)And as always little to no downtime, we did the cut over with 12 guys that worked 12 to 20 hours one weekend.















I wish I had pictures of the pipe work before the service gear arrived, I could not wait and did 99% of the pipe work before the gear was even on site.

Good cut sheets from Square D make that possible and when the gear arrived I punched and tipped it in under the raceways.

Bob



[This message has been edited by iwire (edited 04-12-2004).]

good looking job

Ok lets rip this one to shreds! Just kidding Bob, looks awesome!

Looks nice, Bob.
We're doing very much the same thing now.

2000A 208/120 existing.
3000A 480/277 new.

We're just going to refeed the 208 gear with a 500KVA xfrmr, the 120/208 load is not going to be that much.
I'll get some pics. You'll probably laugh when you see the meters on the front of the switchboards...S

Nice Job Bob!
Gotta love that Square D gear.

Very nice work job Bob.

One question though, did you guys carry the gear down those stairs?

Roger



[This message has been edited by Roger (edited 04-12-2004).]

Very nice.

You'll have to excuse my ignorance with this stuff, as I primarily do residential work.

Does that gear come as "some assembly required" or is it allready assembled? That stuff looks seriously heavy!! Square D has always been know for its robust equipment.

What size conductors are those hanging out of the switchboard?

What type of facility is this?

Peter

[This message has been edited by CTwireman (edited 04-12-2004).]

That gear came as 3 sections, bolt together on site.

Yes it is heavy, those 3 sections together are probably 1100 to 1300 lbs.

The conductors hanging out are 3 sets of 600 kcmil copper to feed the 1200 amp switch gear.

The service conductors are eight sets of 500 kcmils for 3000 amps.

The 1000 KVA transformer inside was a little over 6000 lbs.

No I did not have to bring it down the stairs I did buy a 30 pack and give it to the contractor installing a large conveyor system (the reason for the 480 volt upgrade) the 30 pack gave me the use of his propane folk lift.

The forklift was tagged at 5500 lb capacity so the 6000+ lb transformer was pushing the limits, keep it low.

The outside transformer is close to 15,000 lbs and we opted for riggers to set it for us.

At the time this was a Dot Com home food delivery company, they went out of business.

The upstairs Tennant had 12,000 amps @ 480 (3 x 4000 amps) coming in from the roof along with a another 4000 amps @ 208 coming in near my work.

That tenant was all computers, they had enough generators to pick up all that.

[This message has been edited by iwire (edited 04-12-2004).]

iwire—that looks like a mighty beefy drytype transfomer. Can you post the rated temperature rise? [Often 150, 115 or 80°C]

Assumedly it is 480∆ — 208Y?

Also, my congratulations. The stress and details of cutover work during a tightly scheduled outage always drove me nuts.




[This message has been edited by Bjarney (edited 04-12-2004).]

On the second picture from the bottom does the man door have an self-closer on it?

Yes


No I can not.


This was a tough one, to keep shutdowns to a minimum our work was coordinated with two other electrical contractors.

One contractor was firing up the new POCO 13.8 V double fed switch gear.

A second contractor was handling the 13.8 V feeds and cut over of the second floor tenant that I spoke of.

And then there was us, killing the original feed to the 208 service ad firing up the new 480 service.

Of the 3 electrical contracting companies involved some where union some where not which caused added stress.

In the end all acted professionally which was good because mistakes could kill.

At about 6 AM the contractor handling the POCO work gave me a rotation check and we landed our feeds based on that.

Then 2 hours later when they turned on the power permanently it was backward AHHHH.

This POCO switchgear work was fed from two 13.8 V circuits and one had been landed backward, so when they tried closing a tie breaker the it would open one of the incoming breakers.

I ended up getting these guys to move the elbows on my new pad mount transformer, all was good after that.


Yes, circumvented by us each day, however that door is now outside the electric room.

Once I had my heavy work done a block wall was installed around this area, coming out between that man door and the switch gear.

If you look at the bottom right of the third picture you can see a 'duct tape' stripe laid down on the floor indicating where the wall was going.

It ended making an electric room that was much like Exhibit 110.15 in the hand book.

One large double door opposite the switchgear.

Once the walls went up a fire rated ceiling was installed along with an exhaust fan to the outside.



[This message has been edited by iwire (edited 04-13-2004).]

It's always amazing to see some of this. As a software guy, the biggest I have designed is 100A 208 delta power distribution for some of our testers. BTW, unless this is automotive, I guess the 13.8V is really 13.8kV...
/mike

Thanks Bob. I couldn't see the closer on it, so I was wondering if it was a 1hour room, as required for the big transformer.

YEEEEEEHAW
Now thats some good work!!

DOH! Now I know why the lights where dim!

Sure beats the other way around. {13.8kV on a 13.8V assembly.}

For some reason, 115° seems to fit this one!
Almost like when I first saw the Xformer image, I thought 115° Rise, 5.0% Z!

Scott35

WOW! That thing is huge!

Very impressive!

{Goes back to splice some more signalling wire. The terminals looked small before but now they look microscopic. }

Bob,
Very Nice work!
Sorry to come in so late,
But it looks like a really clean and tidy Install.
Kudos to you and your helper.
In the 3rd pic, is that a Vacuum Cleaner?.
Nice to see that you guys clean up your rubbish!.
In the first pic, what size and type wires are those wires hanging above the Guy working on the panel?
Who is the guy?.
Great all round job, Bob, be proud of that one!.