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electricblue

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I'm looking at upgrading a 100 panel to 200. My question. It's a 1200amp disco in the middle of meters on the left and right. It has 4 sets of 4/0's in the hot gutter. The one that's feeding my panel has 3 100a meters now. 4/0 is only rated for 230? Does that 1 hot gutter set need to change to 600?
 
In the hot gutter coming off the main disco, there are 4 set of 4/0. 1 set of 4/0 taps to 3 100amp panels. I want to upgrade 1 of those to 200. Does that 4/0 need to change to 600?
 
Sounds to me like there are tap rule violations before you even start what you want to do.


there are 4 set of 4/0. (sounds fine for 1200 amp so far but they must be properly paralleled otherwise they are taps)



1 set of 4/0 taps to 3 100amp panels (sounds like taping a tap to me - that is not allowed)

Add: can you give us a little more specific detail of what goes where.
 
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kwired said:
Sounds to me like there are tap rule violations before you even start what you want to do.


there are 4 set of 4/0. (sounds fine for 1200 amp so far but they must be properly paralleled otherwise they are taps)



1 set of 4/0 taps to 3 100amp panels (sounds like taping a tap to me - that is not allowed)
Click to expand...

Trying to learn here. It is a 4/0 tap with taps off it going to 3 panels?
 
Not many 100 amp devices will accept 4/0 conductor - so you will have to tap the 4/0 just to be able to terminate. If the overcurrent protection is above the ampacity of the 4/0 then you have tapped a tap.
 
kwired said:
Sounds to me like there are tap rule violations before you even start what you want to do.


there are 4 set of 4/0. (sounds fine for 1200 amp so far but they must be properly paralleled otherwise they are taps)



1 set of 4/0 taps to 3 100amp panels (sounds like taping a tap to me - that is not allowed)

Add: can you give us a little more specific detail of what goes where.
Click to expand...

6 meters on the left 4 on right. 6 on left have 2 sets of 4/0. 1 set tapped to each 3 100amp panels
 
Showing just the left side only, is this what you have or very close to it?


If so we have tap violations. The 4/0 conductors need to be larger as they have 1200 amps overcurrent protection. You could run separate 3 AWG conductors from the 1200 amp device to each of the 100 amp devices or 1200 amps worth of conductor from the 1200 amp device single or parallel to some kind of splice point and tap from it.
1200awtaps.jpg
 
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kwired said:
Showing just the left side only, is this what you have or very close to it?


If so we have tap violations. The 4/0 conductors need to be larger as they have 1200 amps overcurrent protection. You could run separate 3 AWG conductors from the 1200 amp device to each of the 100 amp devices or 1200 amps worth of conductor from the 1200 amp device single or parallel to some kind of splice point and tap from it.
1200awtaps.jpg
Click to expand...

Thank you Kwired for the illustration... Yes that is the left side. The right side is supposed to look the same but seems to have been messed with as they are not all 100a. So, If paralleled would 4 sets of 350 be 1200amps worth of conductor? Changing the 4/0's to 350.
 
electricblue said:
Thank you Kwired for the illustration... Yes that is the left side. The right side is supposed to look the same but seems to have been messed with as they are not all 100a. So, If paralleled would 4 sets of 350 be 1200amps worth of conductor? Changing the 4/0's to 350.
Click to expand...

Yes that should work.

Original installer likely would have been better off getting a meter center with main disconnect instead of assembling all those components. It also likely is not very easy to find a splicing device that will accomodate 4 - 350's plus 10 ports for the tap conductors. The meter center may have two or three sections that need bolted together but this goes quickly compared to fitting aux gutters, j boxes, etc, and installing all the conductors.
 
kwired said:
Yes that should work.

Original installer likely would have been better off getting a meter center with main disconnect instead of assembling all those components. It also likely is not very easy to find a splicing device that will accomodate 4 - 350's plus 10 ports for the tap conductors. The meter center may have two or three sections that need bolted together but this goes quickly compared to fitting aux gutters, j boxes, etc, and installing all the conductors.
Click to expand...
Not sure if I understand. If your illustration with the 4/0 was changed with 350 to the left and right. A polaris lug for the350 to #3's. Is this right? At the 1200 fused main would be a 4 barrel lug for (4)350's.
 
electricblue said:
Not sure if I understand. If your illustration with the 4/0 was changed with 350 to the left and right. A polaris lug for the350 to #3's. Is this right? At the 1200 fused main would be a 4 barrel lug for (4)350's.
Click to expand...

In my illustration you would have (4) 350's going to the left as well as 4 to the right if there were more taps to the right.

I have a feeling you may be thinking (4) 350's landing in the 1200 amp disconnect with 2 going left and 2 going right. If that is the case you do not have a 1200 amp parallel conductor you have 2 taps that each supply additional taps.

To be able to call them parallel conductors they must be connected together at each end effectively making them one.

Like I said it may be difficult to find a splicing device that will accept 4 - 350's and 10 - 3AWG's. If you wanted separate feeders to left and right you need to come up with 8 barrel lugs for the 1200 amp disconnect, run 4 - 350's left, 4- 350's right, and then come up with splicing devices that will accomodate 4 - 350's for both sides and 6 taps on left, 4 taps right.

If you were starting from scratch a meter center would be the way to go. Good luck trying to straighten this out.
 
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