Maximum service conductors through utility company CT's

[Sparky5150]

I have a client that desires to meter a 3000 amp service and 600 amp serve fed from the same transformer seperately. The utility company wont do this inside the transformer so they require 2 seperate CT cans. What I'm have trouble with is getting CT's around the 3000 amp conductors.

Has anyone done something similar? Can you parallel CT's?

Thanks!!!

 

[beanland]

Bad Idea

Bad Idea

At 3000A, most utilities require switchgear and bar-type metering CTs. Some bar-type go up to 8-12" inner diameter. If I was the utility, I would require CT can and main breaker near the transformer and then let the customer run however they want from there to the loads.(I have my utility hat on.)

 

[hurk27]

I have a client that desires to meter a 3000 amp service and 600 amp serve fed from the same transformer separately. The utility company wont do this inside the transformer so they require 2 separate CT cans. What I'm have trouble with is getting CT's around the 3000 amp conductors.

Has anyone done something similar? Can you parallel CT's?

Thanks!!!

I have never heard of trying to get a CT around conductors when you have a CT can? might be why your having a problem?

We install the ct can and our utility installs the bolt in CT's with the bar across that bolts from line to load, matter of fact they won't even let us supply CT's as it is their cash register so they want control over it.

 

[BAHTAH]

Multi Meteering

Multi Meteering

I have a client that desires to meter a 3000 amp service and 600 amp serve fed from the same transformer seperately. The utility company wont do this inside the transformer so they require 2 seperate CT cans. What I'm have trouble with is getting CT's around the 3000 amp conductors.

Has anyone done something similar? Can you parallel CT's?

Thanks!!!

All the utilities I have worked with install their own CT's, test switch and meter. I would think you would have a switchboard or switchgear line-up with a 4000amp UGP and 3000 amp CT/Mtr with Test block and main on one side and the 600 amp CT/MTR with test block and main on the other. Everything would be bus bars from the UGP through the CT compartments to the mains.
I have seen utilities that provide their CT's in their transformers and if this the norm for your area, you could still provide the gear as I have stated and you can buy bar type ct's and test blocks for metering.

 

[iwire]

I have never heard of trying to get a CT around conductors when you have a CT can? might be why your having a problem?

We install the ct can and our utility installs the bolt in CT's with the bar across that bolts from line to load, matter of fact they won't even let us supply CT's as it is their cash register so they want control over it.

That is how it goes here as we'll but many areas still use doughnut CTs that the conductors must pass through.

 

[Sparky5150]

Thanks for helping out!

I'm not familiar with bar type CT's. The POCO has only mentioned 5-6" donut types.

The issue I think is the length of pull I have from the CT Can to the transformer because I did calculate that the 10 sets of #500kcmil will fit thru them. But the physical install thru the CT's looks pretty brutal.

I may have to punt...

 

[Hv&Lv]

Thanks for helping out!

I'm not familiar with bar type CT's. The POCO has only mentioned 5-6" donut types.

The issue I think is the length of pull I have from the CT Can to the transformer because I did calculate that the 10 sets of #500kcmil will fit thru them. But the physical install thru the CT's looks pretty brutal.

I may have to punt...

There are always options... donuts come with different openings, and there are split core.

http://www.flex-core.com/pdf-files/FCL.pdf
http://www.ekmmetering.com/split-core-ct-3000a-3000a-26-6ma-100mm-hole-diameter-sct-100-3000.html